---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sat 01/08/05: 34 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:54 AM - Strobe power supply rating (j1j2h3@juno.com) 2. 03:30 AM - Re: Ideas on Painting Panel (Bruce Niles) 3. 04:20 AM - Re: LOAD dump comments (D Fritz) 4. 05:13 AM - Instrument Decals (JOHNATHAN MACY) 5. 06:19 AM - Re: LOAD dump comments (Ken) 6. 06:29 AM - Radio Spacing (Brett Ferrell) 7. 06:42 AM - Aeroflash double flash vs. Whelens (luckymacy@comcast.net (lucky)) 8. 06:45 AM - Re: Load dump comments (Eric M. Jones) 9. 06:55 AM - Re: Radio Spacing (John Schroeder) 10. 07:02 AM - Re: Radio Spacing (BobsV35B@aol.com) 11. 07:15 AM - Re: KX-125 Problem Solved (jacklockamy) 12. 07:15 AM - Re: Radio Spacing (Brett Ferrell) 13. 07:31 AM - Re: Ideas on Painting Panel (Jim Stone) 14. 07:31 AM - Re: Radio Spacing (BobsV35B@aol.com) 15. 07:41 AM - Load dump and PM alternators (Gilles Thesee) 16. 07:47 AM - Re: Re: Load dump comments (Ken) 17. 07:55 AM - Re: Aeroflash double flash vs. Whelens (Robert McCallum) 18. 08:35 AM - Modified Z-12 comments (James Redmon) 19. 08:43 AM - Re: Instrument Decals (erie@shelbyvilledesign.com) 20. 09:38 AM - Re: Aeroflash double flash vs. Whelens (Bob Black) 21. 10:10 AM - Re: Instrument Decals (Ernest Kells) 22. 10:30 AM - Re: Radio Spacing (Brett Ferrell) 23. 10:39 AM - Re: Aeroflash double flash vs. Whelens (luckymacy@comcast.net (lucky)) 24. 11:08 AM - Re: Aeroflash double flash vs. Whelens (Scott Jackson) 25. 11:19 AM - FW: Z13A - Basic question ? Help anyone? (Bill Schlatterer) 26. 11:27 AM - Re: Aeroflash double flash vs. Whelens (Paul Messinger) 27. 11:58 AM - Re: Re: Load dump comments clamav-milter version 0.80j on juliet.albedo.net (Paul Messinger) 28. 11:58 AM - Re: LOAD dump comments (Paul Messinger) 29. 12:01 PM - Re: Aeroflash double flash vs. Whelens (luckymacy@comcast.net (lucky)) 30. 12:18 PM - Load dump and shutdown procedures (Paul Messinger) 31. 12:18 PM - Re: Re: Load dump comments (Paul Messinger) 32. 12:36 PM - Re: Re: Load dump comments (Kevin Horton) 33. 12:40 PM - Re: Aeroflash double flash vs. Whelens (luckymacy@comcast.net (lucky)) 34. 12:58 PM - Re: Re: Load dump comments (Paul Messinger) ________________________________ Message 1 _____________________________________ Time: 12:54:33 AM PST US Subject: AeroElectric-List: Strobe power supply rating From: j1j2h3@juno.com --> AeroElectric-List message posted by: j1j2h3@juno.com In looking at strobe power supplies, all of those at Strobesnmore.com are rated in watts. However, the requirements for strobe lights are usually given in joules. How does one make the calculation to determine whether the output is sufficient? I know that one joule is equal to one watt-second, but I don't know how to handle the time factor. I suspect it has to do with flash duration and flashes per minute, but I haven't seen these numbers published for the equipment I've looked at. Jim Hasper - RV-7 Franklin, TN Do not archive ________________________________ Message 2 _____________________________________ Time: 03:30:12 AM PST US From: "Bruce Niles" Subject: Re: AeroElectric-List: Ideas on Painting Panel --> AeroElectric-List message posted by: "Bruce Niles" I live in florida and I can tell you most certainly that when I paint my panel it will be in a light color. Put your hand on top of a black car in the summer and you will remove it quickly, probably with a burnt palm as well. It might act as a large heat sink for you avionics as well?? Food for thought. ----- Original Message ----- From: Subject: Re: AeroElectric-List: Ideas on Painting Panel > --> AeroElectric-List message posted by: BobsV35B@aol.com > > > In a message dated 1/7/2005 3:47:14 P.M. Central Standard Time, > cajole76@ispwest.com writes: > > There is a big difference in glare factor between an airliner panel and > an RV. Due to the relatively narrow glare shield, and bubble canopy, > the RV with a light colored panel is going to expose you to a lot more > reflectivity. Like you Bob, I like the looks of the light colored > panels, but I'm not sure I would want to put up with all those > reflections produced in the RV. > > > Could be. I have never flown an RV. > > However, I fly my Bonanza a lot at night. It has a light tan panel. > > I also had the pleasure of putting four and a half hours in a USAF T-38 a > couple of years ago. It had a light grey panel and somewhat of a bubble > canopy > > I think the light colored panels are much more comfortable to use and I > have > never noted any reflections due to them. > > As you say: "But hey, what ever floats your boat" > > Happy Skies, > > Old Bob > AKA > Bob Siegfried > Ancient Aviator > Stearman N3977A > Brookeridge Airpark LL22 > Downers Grove, IL 60516 > 630 985-8502 > > Do Not Archive > > > ________________________________ Message 3 _____________________________________ Time: 04:20:51 AM PST US From: D Fritz Subject: Re: AeroElectric-List: LOAD dump comments --> AeroElectric-List message posted by: D Fritz "Thus the Crowbar OVP action not only shorts the buss it creates a load dump, neither action is desirable or necessary. OVP protection does not need to be crowbar in nature and surely not a unlimited current short." In reading the above, it sounds like we should be looking at another method of overvoltage protection, am I understanding this correctly? Does anyone have suggested architectures? Is this load dump only an issue with internally regulated alternators, or do externally regulated alternators just have protection already built in? In another thread, Gary raises the question of why we don't just attach the alternator directly to the battery (vice through the main contactor) to mitigate the load dump issue, any comments out there on why we should or should not do this? Dan Fritz --------------------------------- ________________________________ Message 4 _____________________________________ Time: 05:13:27 AM PST US From: JOHNATHAN MACY Subject: AeroElectric-List: Instrument Decals --> AeroElectric-List message posted by: JOHNATHAN MACY At one time on the web I came across a company that will make decals / overlays per your drawing for instrument panels. For example, they could make a decal that could go across you panel above all the switches. Now I can not find them. Any idea? - Thx - Johnathan ________________________________ Message 5 _____________________________________ Time: 06:19:41 AM PST US From: Ken Subject: Re: AeroElectric-List: LOAD dump comments clamav-milter version 0.80j on juliet.albedo.net --> AeroElectric-List message posted by: Ken Well the advantage of using a proven OV module is that it should rarely nuisance or falsely trip. In a real OV situation the alternator is already going full bore so there is no disadvantage of the crowbar method. Perhaps even an advantage as it draws down the voltage even before the OV contactor opens. Yes there have been a few nuisance trips mentioned here but I don't recall any associated equipment damage. I don't recall any nuisance trips since the last module re-design?? The advantage of the external VR alternator is that you don't need the OV contactor. My internal VR alternator is connected through a fuse to the battery (not through the battery contactor) but that pesky OV contactor is still necessary. We had a discussion a year or so ago on alternative OV protection methods and this is still what I decided to do. However I also chose to use a small 40 amp alternator to further limit the magnitude of the energy that could be stored in the stator windings and the amount of excess alternator current available. So my battery contactor interupts current to all the things that do not power any of my engine requirements, it does not disconnect either of my alternators from their respective batteries. Paul - thanks for expanding on the use of the three 1.5k devices instead of the 5kp18. Ken D Fritz wrote: >--> AeroElectric-List message posted by: D Fritz > >"Thus the Crowbar OVP action not only shorts the buss it creates a load dump, > neither action is desirable or necessary. OVP protection does not need to be > crowbar in nature and surely not a unlimited current short." > >In reading the above, it sounds like we should be looking at another method of overvoltage protection, am I understanding this correctly? Does anyone have suggested architectures? Is this load dump only an issue with internally regulated alternators, or do externally regulated alternators just have protection already built in? In another thread, Gary raises the question of why we don't just attach the alternator directly to the battery (vice through the main contactor) to mitigate the load dump issue, any comments out there on why we should or should not do this? > >Dan Fritz > > ________________________________ Message 6 _____________________________________ Time: 06:29:24 AM PST US From: "Brett Ferrell" Subject: AeroElectric-List: Radio Spacing --> AeroElectric-List message posted by: "Brett Ferrell" Bob/folks, Is there an easy way to get my radio spacing correct? I couldn't buy all of my radios right away, but I did get their mounting trays. Can I just stack these one on top of the other and mate their front edges to the front edge of my panel, or should I allow some space between the mounting boxes (vertically), and if so, how much? Thanks. Brett ________________________________ Message 7 _____________________________________ Time: 06:42:21 AM PST US From: luckymacy@comcast.net (lucky) Subject: AeroElectric-List: Aeroflash double flash vs. Whelens --> AeroElectric-List message posted by: luckymacy@comcast.net (lucky) Has anyone looked into the single vs. double flash AEROFLASH NAV/STROBE/POSITION LIGHT KITS and determined if the "intensity" is measurably less than the single flash? Just observing these lights in single flash form vs whelens in formation flight leaves my to personally believe that the whelens aren't worth any the extra $ for them but still people seem to pass up these kits often enough to go for the Whelens that I keep asking why... http://www.aircraftspruce.com/catalog/elpages/aerofllightkits.php Lucky -------------- Original message -------------- > --> AeroElectric-List message posted by: j1j2h3@juno.com > > > In looking at strobe power supplies, all of those at Strobesnmore.com are > rated in watts. However, the requirements for strobe lights are usually > given in joules. How does one make the calculation to determine whether > the output is sufficient? I know that one joule is equal to one > watt-second, but I don't know how to handle the time factor. I suspect > it has to do with flash duration and flashes per minute, but I haven't > seen these numbers published for the equipment I've looked at. > > > Jim Hasper - RV-7 > Franklin, TN > > Do not archive > > > > > > Has anyone looked into the single vs. double flash AEROFLASH NAV/STROBE/POSITION LIGHT KITS and determined if the "intensity" is measurably less than the single flash? Just observing these lights in single flash form vs whelens in formation flight leaves my to personally believe that the whelens aren't worth any the extra $ for them but still people seem to pass up these kits often enough to go for the Whelens that I keep asking why... http://www.aircraftspruce.com/catalog/elpages/aerofllightkits.php Lucky -------------- Original message -------------- -- AeroElectric-List message posted by: j1j2h3@juno.com In looking at strobe power supplies, all of those at Strobesnmore.com are rated in watts. However, the requirements for strobe lights are usually given in joules. How does one make the calculation to determine whether the output is sufficient? I know that one joule is equal to one watt-second, but I don't know how to handle the time factor. I suspect it has to do with flash duration and flashes per minute, but I haven't seen these numbers published for the equipment I've looked at. Jim Hasper - RV-7 Franklin, TN Do not archive The AeroElectric-List Email Forum - /www.matronics.com/aeroelectric-list ________________________________ Message 8 _____________________________________ Time: 06:45:39 AM PST US From: "Eric M. Jones" Subject: AeroElectric-List: Re: Load dump comments --> AeroElectric-List message posted by: "Eric M. Jones" --> AeroElectric-List message posted by: D Fritz >"Thus the Crowbar OVP action not only shorts the buss it creates a load dump, > neither action is desirable or necessary. OVP protection does not need to >be crowbar in nature and surely not a unlimited current short." >In reading the above, it sounds like we should be looking at another method of >overvoltage protection, am I understanding this correctly? Does anyone have suggested >architectures? Dan, I think the old crowbar is dead. When batteries had high internal resistance and the only method of disconnecting a circuit was a fuse, and the need for greater control of OV was less important---maybe crowbar OVs were okay. Today it seems unreasonable to me to take this approach. Would you crowbar your computer? I used to sell both crowbar and non-crowbar OVP and I never really liked the crowbar method. Paul Messinger's testing has shown that the old crowbar method drops humongous (~1000A) currents through the busses and tops it off with a load dump. I just can't think of any reason why one would want to do this when simpler, kinder, gentler methods are available. I sell these on my website of course. I call them Linear OVPs http://www.periheliondesign.com/ovp.htm When a monitored voltage stays above 16.2 volts for more than 200 milliSeconds (glitch filter), the Linear OVP politely disconnects the circuit. Okay so it's not very macho.... >Is this load dump only an issue with internally regulated alternators, or do externally regulated alternators just have protection already built in? Load dump is an issue with any source of power that uses a rotating conductor in a magnetic field. By the way, overvoltage and load dump are related in that they both have associated overvoltages. Load dump is a strictly transient OV condition caused by disconnecting a load, but an overvoltage condition can be caused by a failed regulator or other causes and may be long term. Both need to be addressed. >In another thread, Gary raises the question of why we don't just attach the alternator directly to the battery (vice through the main contactor) >to mitigate the load dump issue, any comments out there on why we should >or should not do this? .........Dan Fritz Just preventing the battery from being disconnected would help, but would cause it's own problems. Besides, events other than battery disconnection can cause load dumps, like a circuit breaker or fuse popping or a big load being turned off. Regards, Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge MA 01550-2705 Phone (508) 764-2072 Email: emjones@charter.net "The man who carries a cat by the tail learns something that can be learned in no other way." --Mark Twain ________________________________ Message 9 _____________________________________ Time: 06:55:44 AM PST US From: "John Schroeder" Subject: Re: AeroElectric-List: Radio Spacing --> AeroElectric-List message posted by: "John Schroeder" Brett I would download the installation manuals for the items you intend to buy and check the spacing they recommend. Another problem arises if you buy different brands (Garmin vs Garmin AT vs Tru Trak, for example.)The bezels may not line up exactly and you could get one box sticking out past the others. This would not be by a lot, but somewhat noticeable. You can compensate by mounting the trays a bit in front or behind the one above or below. I would then build the stack of trays with the spacing required. ie. mount the trays on rails and also adding straps (braces) on the aft ends of the trays as well. One problem that comes up in all of this is if one of the trays is mounted slightly twisted in the rails. You could then expect the boxe to bind a bit when sliding it into the tray and also it may not seat completely into the back plane jacks/plugs. Contact me off line if you want a copy of a "builder's hint" paper that reflects the experiences of two Lancair ES builders' panel construction. Hope this helps, John >Is there an easy way to get my radio spacing correct? I couldn't buy all of my radios right away, but I did get their mounting trays. Can I just stack these one on top of the other and mate their front edges to the front edge of my panel, or should I allow some space between the mounting boxes (vertically), and if so, how much? Thanks. > >Brett > ________________________________ Message 10 ____________________________________ Time: 07:02:29 AM PST US From: BobsV35B@aol.com Subject: Re: AeroElectric-List: Radio Spacing --> AeroElectric-List message posted by: BobsV35B@aol.com In a message dated 1/8/2005 8:29:52 A.M. Central Standard Time, bferrell@123mail.net writes: Bob/folks, Is there an easy way to get my radio spacing correct? I couldn't buy all of my radios right away, but I did get their mounting trays. Can I just stack these one on top of the other and mate their front edges to the front edge of my panel, or should I allow some space between the mounting boxes (vertically), and if so, how much? Thanks. Brett Different Bob here, but if you think you may be readjusting the sleeves in the future, I would strongly consider using a set of RadioRax rails. They not only make the between set adjustments easy, they are FAA approved for mounting the radios with no rear support. I installed a set recently and they seem to work very well. Should make further changes a snap! Happy Skies, Old Bob AKA Bob Siegfried Ancient Aviator Stearman N3977A Brookeridge Airpark LL22 Downers Grove, IL 60516 630 985-8502 ________________________________ Message 11 ____________________________________ Time: 07:15:46 AM PST US From: "jacklockamy" Subject: Re: AeroElectric-List: KX-125 Problem Solved --> AeroElectric-List message posted by: "jacklockamy" YES! You still need the jumper..... My buddy's set-up was exactly like yours (stand-alone unit, no CDI). His thinking was also liken to yours..... no CDI, guess I don't need the jumper. WRONG. Install the jumper and your KX-125 will work as advertised. Thanks again to all those list members who helped solve the problem we were having. Jack Lockamy Camarillo, CA ________________________________ Message 12 ____________________________________ Time: 07:15:46 AM PST US From: "Brett Ferrell" Subject: Re: AeroElectric-List: Radio Spacing --> AeroElectric-List message posted by: "Brett Ferrell" Yea, I looked at those, and really wanted to use them, but the cant in my velocity panel procludes their use, they didn't have a set thin enough to utilize unfortunately. Brett ----- Original Message ----- From: Subject: Re: AeroElectric-List: Radio Spacing > --> AeroElectric-List message posted by: BobsV35B@aol.com > > > In a message dated 1/8/2005 8:29:52 A.M. Central Standard Time, > bferrell@123mail.net writes: > > Bob/folks, > > Is there an easy way to get my radio spacing correct? I couldn't buy all > of > my radios right away, but I did get their mounting trays. Can I just > stack > these one on top of the other and mate their front edges to the front > edge of > my panel, or should I allow some space between the mounting boxes > (vertically), and if so, how much? Thanks. > > Brett > > > Different Bob here, but if you think you may be readjusting the sleeves > in > the future, I would strongly consider using a set of RadioRax rails. > They not > only make the between set adjustments easy, they are FAA approved for > mounting the radios with no rear support. > > I installed a set recently and they seem to work very well. Should make > further changes a snap! > > Happy Skies, > > Old Bob > AKA > Bob Siegfried > Ancient Aviator > Stearman N3977A > Brookeridge Airpark LL22 > Downers Grove, IL 60516 > 630 985-8502 > > > ________________________________ Message 13 ____________________________________ Time: 07:31:39 AM PST US From: "Jim Stone" Subject: Re: AeroElectric-List: Ideas on Painting Panel --> AeroElectric-List message posted by: "Jim Stone" White is too reflective. You won't like the reflections on your canopy. Besides, how often do you touch your instrument panel? Go with medium to dark shades for the panel. Jim HRII ----- Original Message ----- From: "Bruce Niles" Subject: Re: AeroElectric-List: Ideas on Painting Panel > --> AeroElectric-List message posted by: "Bruce Niles" > > I live in florida and I can tell you most certainly that when I paint my > panel it will be in a light color. Put your hand on top of a black car in > the summer and you will remove it quickly, probably with a burnt palm as > well. It might act as a large heat sink for you avionics as well?? Food > for thought. > ----- Original Message ----- > From: > To: > Subject: Re: AeroElectric-List: Ideas on Painting Panel > > >> --> AeroElectric-List message posted by: BobsV35B@aol.com >> >> >> In a message dated 1/7/2005 3:47:14 P.M. Central Standard Time, >> cajole76@ispwest.com writes: >> >> There is a big difference in glare factor between an airliner panel and >> an RV. Due to the relatively narrow glare shield, and bubble canopy, >> the RV with a light colored panel is going to expose you to a lot more >> reflectivity. Like you Bob, I like the looks of the light colored >> panels, but I'm not sure I would want to put up with all those >> reflections produced in the RV. >> >> >> Could be. I have never flown an RV. >> >> However, I fly my Bonanza a lot at night. It has a light tan panel. >> >> I also had the pleasure of putting four and a half hours in a USAF T-38 a >> couple of years ago. It had a light grey panel and somewhat of a bubble >> canopy >> >> I think the light colored panels are much more comfortable to use and I >> have >> never noted any reflections due to them. >> >> As you say: "But hey, what ever floats your boat" >> >> Happy Skies, >> >> Old Bob >> AKA >> Bob Siegfried >> Ancient Aviator >> Stearman N3977A >> Brookeridge Airpark LL22 >> Downers Grove, IL 60516 >> 630 985-8502 >> >> Do Not Archive >> >> >> > > > ________________________________ Message 14 ____________________________________ Time: 07:31:49 AM PST US From: BobsV35B@aol.com Subject: Re: AeroElectric-List: Radio Spacing --> AeroElectric-List message posted by: BobsV35B@aol.com In a message dated 1/8/2005 9:16:37 A.M. Central Standard Time, bferrell@123mail.net writes: --> AeroElectric-List message posted by: "Brett Ferrell" Yea, I looked at those, and really wanted to use them, but the cant in my velocity panel procludes their use, they didn't have a set thin enough to utilize unfortunately. Brett Good Morning Brent, I used the RK 1020 as they were no bigger than the aluminum angle most folks use. Radio Rax has come out with a set of canted racks to be used for the Bonanza and another set for the Baron. The ones for the Baron should work well for any canted panel. The ones for the Bonanza don't work as well because it moves the radios a half inch to the right and wastes a bit of panel space. That came about because they wanted to use the same right hand extrusion for both. But that is not pertinent unless you are putting them in a Bonanza! For a canted panel in a home built, I would seriously consider the Radio Rax designed for the Baron. For a Bonanza, I would recommend using the RK 1020 mounted in the original Bonanza canted panel. See: _www.RadioRax.com_ (http://www.RadioRax.com) Happy Skies, Old Bob AKA Bob Siegfried Ancient Aviator Stearman N3977A Brookeridge Airpark LL22 Downers Grove, IL 60516 630 985-8502 ________________________________ Message 15 ____________________________________ Time: 07:41:10 AM PST US From: "Gilles Thesee" Subject: AeroElectric-List: Load dump and PM alternators --> AeroElectric-List message posted by: "Gilles Thesee" Hi Eric and all, Please pardon me for having followed the load dump thread with a casual eye. > Load dump is an issue with any source of power that uses a rotating > conductor in a magnetic field. By the way, overvoltage and load dump are > related in that they both have associated overvoltages. Load dump is a > strictly transient OV condition caused by disconnecting a load, but an > overvoltage condition can be caused by a failed regulator or other causes > and may be long term. Both need to be addressed. > Question : is the load dump issue the same for permanent magnet alternators ? At first glance I would say there are differences, but would one of you experts tell me if I have to reconsider my "ordinary" crowbar OV module setup ? Thanks. Regards, Gilles Thesee Grenoble, France ________________________________ Message 16 ____________________________________ Time: 07:47:55 AM PST US From: Ken Subject: Re: AeroElectric-List: Re: Load dump comments clamav-milter version 0.80j on juliet.albedo.net --> AeroElectric-List message posted by: Ken Sure that sounds scary but I'll wait for the report before getting concerned. With 6 feet of 18awg wire in series with a C/B, an SCR, and several connections it may be possible to get a couple of hundred amps of instantaneous current flowing but so what? It is drawing down the voltage which is what we want. The interesting thing to me is a nuisance trip. It sounds like it is possible to ramp up the alternator output during the delay (40 ms?) waiting for the OV contactor to open. However I haven't seen any reason to be concerned about that yet and I will await the report. If it turns out to be a concern, perhaps I will replace my OV C/B with a fuse for quicker current interuption. A few folks have advocated transorbs to tame these scenarios for several years now and it seems like they do the job just fine. I really really appreciate it when someone like Paul or Bob documents and shares the numbers so that I have more than anecdotal evidence that my transorbs are up to the task that I installed them for. Sorry if I sound snippy. I appreciate being able to purchase an elegant solution when I want to. After all that does help the entire homebuilt movement. However the fun of homebuilt aviation for me is being able to try different things and sharing public domain solutions like we do here. It is great that we can purchase a OV module from B&C (or Eric) but it is really really neat that BOB also gives us the design to build our own and experiment with if we choose. I don't think I really even saved any money by building my own OV module, but I know how it works, how to adjust it, how to repair it, and I can keep a spare around if I choose. Well yes I guess the second one I needed cost me next to nothing but the knowledge gained was still worth more than that saving and was definately worth the time invested. Ken snip >I used to sell both crowbar and non-crowbar OVP and I never really liked the >crowbar method. Paul Messinger's testing has shown that the old crowbar >method drops humongous (~1000A) currents through the busses and tops it off >with a load dump. I just can't think of any reason why one would want to do >this when simpler, kinder, gentler methods are available. > > snip ________________________________ Message 17 ____________________________________ Time: 07:55:17 AM PST US From: Robert McCallum Subject: Re: AeroElectric-List: Aeroflash double flash vs. Whelens --> AeroElectric-List message posted by: Robert McCallum The question isn't so much one of "how intense is the flash" but one of human biometrics. The human eye and brain react extremely well to motion or suddenness (if that's a word) of an event. The single flash strobe gets your attention that something is there. But where?? By the time your brain has recognized the existence of the flash it's gone. This is the reason companies like whelan have developed the multiflash units. The first part of the flash gets your attention the subsequent flash or flashes gives your brain time to home in on where it is. It's much easier to see a moving aircraft than one that' s stationary against it's background for instance. Now suppose that lighting conditions, glare, or visibility are such that the only thing you see of a plane is the flash of the strobe. With a single flash it's moved before you can zero in on the location. With "multiflash" you get to adjust your vision on the second, third, or fourth part of the flash, thus being able to locate the aircraft before it's moved to a new location until the next flash sequence. MUCH easier and less stressfu, especially in marginal conditions. Now don't you want your pride ands joy to be the one easy to distinguish and pick out of the sky instead of the one where the other guy is saying to himself " I know I saw something out there somewhere"? Bob McC lucky wrote: >--> AeroElectric-List message posted by: luckymacy@comcast.net (lucky) > >Has anyone looked into the single vs. double flash AEROFLASH NAV/STROBE/POSITION LIGHT KITS and determined if the "intensity" is measurably less than the single flash? Just observing these lights in single flash form vs whelens in formation flight leaves my to personally believe that the whelens aren't worth any the extra $ for them but still people seem to pass up these kits often enough to go for the Whelens that I keep asking why... > >http://www.aircraftspruce.com/catalog/elpages/aerofllightkits.php > >Lucky > > ________________________________ Message 18 ____________________________________ Time: 08:35:49 AM PST US From: "James Redmon" Subject: AeroElectric-List: Modified Z-12 comments --> AeroElectric-List message posted by: "James Redmon" I have a builder buddy (not on list) that is in the process of wiring his plane using a slightly modified Z-12 with the addition of an aux battery wired in per Figure 17-6. He's asked me for my comments on the "modifications" he made and I'm not too sure how to respond. It a "I would not do it this way, but that doesn't mean he shouldn't", kinda thing. The main parts of Z-12 are not changed other than adding the second battery and contactor I mentioned above. The thing he changed was in the switching of the main/aux batteries and the main/aux alternators. E-bus is run off the main battery only - just like in Figure 17-6. For the switches, he has used 2 DPST switches - one simultaneously activates the main battery and main alternator together, and the second activates the aux battery and the aux alternator together. There is no single "master" switch in this combination, but there is also no way to run the aux alternator from the main battery only. There are still two ways to send power to the main bus - main on, aux on (or both of those on), and the e-bus can be powered from the main battery via a separate e-bus switch. However, there is now no way to isolate an alternator only from it's respective battery. Now, for you "theory" folks out there...is this an acceptable design modification? It certainly saves panel switch space (two vs 4 switch holes), but I'd like to hear some of the "knows more than me" crowd's opinions on coupling the battery and alt switches together. Thanks! James Redmon Berkut #013 N97TX http://www.berkut13.com ________________________________ Message 19 ____________________________________ Time: 08:43:33 AM PST US From: erie@shelbyvilledesign.com Subject: Re: AeroElectric-List: Instrument Decals --> AeroElectric-List message posted by: erie@shelbyvilledesign.com Johnathan, contact me off list erie Quoting JOHNATHAN MACY : > --> AeroElectric-List message posted by: JOHNATHAN MACY > > > At one time on the web I came across a company that will make decals / > overlays per your drawing for instrument panels. For example, they could make > a decal that could go across you panel above all the switches. Now I can not > find them. Any idea? - Thx - Johnathan > > > > > > > ________________________________ Message 20 ____________________________________ Time: 09:38:56 AM PST US From: "Bob Black" Subject: RE: AeroElectric-List: Aeroflash double flash vs. Whelens --> AeroElectric-List message posted by: "Bob Black" Like some other builders (see http://www.rv7.us/daily040908%20w.htm - this site has a sequence of strobes and position lights) I'm using emergency vehicle systems that put out just as much brightness and allow you to tailor the flash sequence to what you want. You need to build or buy separate position lights if you want to do that. I have priced these systems and they seem to cost less than half of what the aviation stuff costs. What are the downsides? Bob Rv7 wings -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of lucky Subject: AeroElectric-List: Aeroflash double flash vs. Whelens --> AeroElectric-List message posted by: luckymacy@comcast.net (lucky) Has anyone looked into the single vs. double flash AEROFLASH NAV/STROBE/POSITION LIGHT KITS and determined if the "intensity" is measurably less than the single flash? Just observing these lights in single flash form vs whelens in formation flight leaves my to personally believe that the whelens aren't worth any the extra $ for them but still people seem to pass up these kits often enough to go for the Whelens that I keep asking why... http://www.aircraftspruce.com/catalog/elpages/aerofllightkits.php Lucky -------------- Original message -------------- > --> AeroElectric-List message posted by: j1j2h3@juno.com > > > In looking at strobe power supplies, all of those at Strobesnmore.com are > rated in watts. However, the requirements for strobe lights are usually > given in joules. How does one make the calculation to determine whether > the output is sufficient? I know that one joule is equal to one > watt-second, but I don't know how to handle the time factor. I suspect > it has to do with flash duration and flashes per minute, but I haven't > seen these numbers published for the equipment I've looked at. > > > Jim Hasper - RV-7 > Franklin, TN > > Do not archive > > > > > > Has anyone looked into the single vs. double flash AEROFLASH NAV/STROBE/POSITION LIGHT KITS and determined if the "intensity" is measurably less than the single flash? Just observing these lights in single flash form vs whelens in formation flight leaves my to personally believe that the whelens aren't worth any the extra $ for them but still people seem to pass up these kits often enough to go for the Whelens that I keep asking why... http://www.aircraftspruce.com/catalog/elpages/aerofllightkits.php Lucky -------------- Original message -------------- -- AeroElectric-List message posted by: j1j2h3@juno.com In looking at strobe power supplies, all of those at Strobesnmore.com are rated in watts. However, the requirements for strobe lights are usually given in joules. How does one make the calculation to determine whether the output is sufficient? I know that one joule is equal to one watt-second, but I don't know how to handle the time factor. I suspect it has to do with flash duration and flashes per minute, but I haven't seen these numbers published for the equipment I've looked at. Jim Hasper - RV-7 Franklin, TN Do not archive The AeroElectric-List Email Forum - /www.matronics.com/aeroelectric-list ________________________________ Message 21 ____________________________________ Time: 10:10:25 AM PST US From: "Ernest Kells" Subject: Re: AeroElectric-List: Instrument Decals --> AeroElectric-List message posted by: "Ernest Kells" Jonathan and Others: I think that you are looking for http://engravers.net/aircraft/standard_placards.htm They provide a lot more design flexibility than you request. At $0.50 per word I plan to use them for most or all of my panel. In addition, I will also probably use them for engraving my fuel caps. Look at the RV example - meets my needs perfectly (seems a little pricey for two colour matched caps - - but very, very slick). >> At one time on the web I came across a company that will make decals / overlays per your drawing for instrument panels. For example, they could make a decal that could go across you panel above all the switches. Now I can not find them. Any idea? - Thx - Johnathan << ________________________________ Message 22 ____________________________________ Time: 10:30:05 AM PST US From: "Brett Ferrell" Subject: Re: AeroElectric-List: Radio Spacing --> AeroElectric-List message posted by: "Brett Ferrell" The Velocity's cant doesn't have enough space for angles on both sides, it's barely wider than the radios, you actually mount a piece of flat 1/4" bar stock on that side, and angle AL on the other, so the canted system is still too wide, sadly. Brett ----- Original Message ----- From: Subject: Re: AeroElectric-List: Radio Spacing > --> AeroElectric-List message posted by: BobsV35B@aol.com > > > In a message dated 1/8/2005 9:16:37 A.M. Central Standard Time, > bferrell@123mail.net writes: > > --> AeroElectric-List message posted by: "Brett Ferrell" > > > Yea, I looked at those, and really wanted to use them, but the cant in my > velocity panel procludes their use, they didn't have a set thin enough to > utilize unfortunately. > > Brett > > > Good Morning Brent, > > I used the RK 1020 as they were no bigger than the aluminum angle most > folks > use. > > Radio Rax has come out with a set of canted racks to be used for the > Bonanza > and another set for the Baron. The ones for the Baron should work well > for > any canted panel. The ones for the Bonanza don't work as well because it > moves the radios a half inch to the right and wastes a bit of panel > space. > > That came about because they wanted to use the same right hand extrusion > for > both. But that is not pertinent unless you are putting them in a Bonanza! > > For a canted panel in a home built, I would seriously consider the Radio > Rax > designed for the Baron. > > For a Bonanza, I would recommend using the RK 1020 mounted in the original > Bonanza canted panel. > > See: _www.RadioRax.com_ (http://www.RadioRax.com) > > Happy Skies, > > Old Bob > AKA > Bob Siegfried > Ancient Aviator > Stearman N3977A > Brookeridge Airpark LL22 > Downers Grove, IL 60516 > 630 985-8502 > > > ________________________________ Message 23 ____________________________________ Time: 10:39:26 AM PST US From: luckymacy@comcast.net (lucky) Subject: Re: AeroElectric-List: Aeroflash double flash vs. Whelens --> AeroElectric-List message posted by: luckymacy@comcast.net (lucky) Hi, I agree which is why I am interested in the doubleflashers to begin with. Since the Aeroflash is a weaker flash "on paper" (which I can'f find on the internet anymore), I am wondering if someone has found any info on the double flash version's lumens/joules/subjective viewing/whatever to do some kind of rough compare to see if it was much weaker "on paper" than the single flash version. The problem is I can't find the detailed info on their 152-0007 or their 152-0011 power supplys. I used to be able to. It doesn't appear to be on their web site anymore. Maybe someone who bought them has the info. -------------- Original message -------------- > --> AeroElectric-List message posted by: Robert McCallum > > > The question isn't so much one of "how intense is the flash" but one of > human biometrics. The human eye and brain react extremely well to > motion or suddenness (if that's a word) of an event. The single flash > strobe gets your attention that something is there. But where?? By the > time your brain has recognized the existence of the flash it's gone. > This is the reason companies like whelan have developed the multiflash > units. The first part of the flash gets your attention the subsequent > flash or flashes gives your brain time to home in on where it is. It's > much easier to see a moving aircraft than one that' s stationary against > it's background for instance. Now suppose that lighting conditions, > glare, or visibility are such that the only thing you see of a plane is > the flash of the strobe. With a single flash it's moved before you can > zero in on the location. With "multiflash" you get to adjust your vision > on the second, third, or fourth part of the flash, thus being able to > locate the aircraft before it's moved to a new location until the next > flash sequence. MUCH easier and less stressfu, especially in marginal > conditions. Now don't you want your pride ands joy to be the one easy to > distinguish and pick out of the sky instead of the one where the other > guy is saying to himself " I know I saw something out there somewhere"? > > Bob McC > > lucky wrote: > > >--> AeroElectric-List message posted by: luckymacy@comcast.net (lucky) > > > >Has anyone looked into the single vs. double flash AEROFLASH > NAV/STROBE/POSITION LIGHT KITS and determined if the "intensity" is measurably > less than the single flash? Just observing these lights in single flash form vs > whelens in formation flight leaves my to personally believe that the whelens > aren't worth any the extra $ for them but still people seem to pass up these > kits often enough to go for the Whelens that I keep asking why... > > > >http://www.aircraftspruce.com/catalog/elpages/aerofllightkits.php > > > >Lucky > > > > > > > > > > Hi, I agree which is why I am interested in the doubleflashers to begin with. Since the Aeroflash is a weaker flash "on paper" (which I can'f find on the internet anymore), I am wondering if someone has found any info on the double flash version's lumens/joules/subjective viewing/whatever to do some kind of rough compare to see if it was much weaker "on paper" than the single flash version. The problem is I can't find the detailed info on their 152-0007 or their 152-0011 power supplys. I used to be able to. It doesn't appear to be on their web site anymore. Maybe someone who bought them has the info. -------------- Original message -------------- -- AeroElectric-List message posted by: Robert McCallum The question isn't so much one of "how intense is the flash" but one of human biometrics. The human eye and brain react extremely well to motion or suddenness (if that's a word) of an event. The single flash strobe gets your attention that something is there. But where?? By the time your brain has recognized the existence of the flash it's gone. This is the reason companies like whelan have developed the multiflash units. The first part of the flash gets your attention the subsequent flash or flashes gives your brain time to home in on where it is. It's much easier to see a moving aircraft than one that' s stationary against it's backg round for instance. Now suppose that lighting conditions, glare, or visibility are such that the only thing you see of a plane is the flash of the strobe. With a single flash it's moved before you can zero in on the location. With "multiflash" you get to adjust your vision on the second, third, or fourth part of the flash, thus being able to locate the aircraft before it's moved to a new location until the next flash sequence. MUCH easier and less stressfu, especially in marginal conditions. Now don't you want your pride ands joy to be the one easy to distinguish and pick out of the sky instead of the one where the other guy is saying to himself " I know I saw something out there somewhere"? Bob McC lucky wrote: -- AeroElectric-List message posted by: luckymacy@comcast.net (lucky) Has anyone looked into the single vs. double flash AEROFLASH NAV/STROBE/POSITION LIGHT KITS and determined if the "intensity" is measurably less than the single flash? Just observing these lights in single flash form vs whelens in formation flight leaves my to personally believe that the whelens aren't worth any the extra $ for them but still people seem to pass up these kits often enough to go for the Whelens that I keep asking why... http://www.aircraftspruce.com/catalog/elpages/aerofllightkits.php Lucky ============================================================= ================================================== ________________________________ Message 24 ____________________________________ Time: 11:08:23 AM PST US From: "Scott Jackson" Subject: Re: AeroElectric-List: Aeroflash double flash vs. Whelens --> AeroElectric-List message posted by: "Scott Jackson" Has Aeroflash changed their power supplies? The reason I didn't install Aeroflash-although the price was attractive-was the surging that its power supply would induce in the electrical system, according to " The Electric Connection" manual. Scott in VAncouver 165 hrs on RV-6 police-car strobe power supply, Whelen heads ----- Original Message ----- From: "lucky" Subject: Re: AeroElectric-List: Aeroflash double flash vs. Whelens > --> AeroElectric-List message posted by: luckymacy@comcast.net (lucky) > > Hi, > I agree which is why I am interested in the doubleflashers to begin with. > > Since the Aeroflash is a weaker flash "on paper" (which I can'f find on > the internet anymore), I am wondering if someone has found any info on the > double flash version's lumens/joules/subjective viewing/whatever to do > some kind of rough compare to see if it was much weaker "on paper" than > the single flash version. The problem is I can't find the detailed info > on their 152-0007 or their 152-0011 power supplys. I used to be able to. > It doesn't appear to be on their web site anymore. Maybe someone who > bought them has the info. > > -------------- Original message -------------- > >> --> AeroElectric-List message posted by: Robert McCallum >> >> >> The question isn't so much one of "how intense is the flash" but one of >> human biometrics. The human eye and brain react extremely well to >> motion or suddenness (if that's a word) of an event. The single flash >> strobe gets your attention that something is there. But where?? By the >> time your brain has recognized the existence of the flash it's gone. >> This is the reason companies like whelan have developed the multiflash >> units. The first part of the flash gets your attention the subsequent >> flash or flashes gives your brain time to home in on where it is. It's >> much easier to see a moving aircraft than one that' s stationary against >> it's background for instance. Now suppose that lighting conditions, >> glare, or visibility are such that the only thing you see of a plane is >> the flash of the strobe. With a single flash it's moved before you can >> zero in on the location. With "multiflash" you get to adjust your vision >> on the second, third, or fourth part of the flash, thus being able to >> locate the aircraft before it's moved to a new location until the next >> flash sequence. MUCH easier and less stressfu, especially in marginal >> conditions. Now don't you want your pride ands joy to be the one easy to >> distinguish and pick out of the sky instead of the one where the other >> guy is saying to himself " I know I saw something out there somewhere"? >> >> Bob McC >> >> lucky wrote: >> >> >--> AeroElectric-List message posted by: luckymacy@comcast.net (lucky) >> > >> >Has anyone looked into the single vs. double flash AEROFLASH >> NAV/STROBE/POSITION LIGHT KITS and determined if the "intensity" is >> measurably >> less than the single flash? Just observing these lights in single flash >> form vs >> whelens in formation flight leaves my to personally believe that the >> whelens >> aren't worth any the extra $ for them but still people seem to pass up >> these >> kits often enough to go for the Whelens that I keep asking why... >> > >> >http://www.aircraftspruce.com/catalog/elpages/aerofllightkits.php >> > >> >Lucky >> > >> > >> >> >> >> >> >> > > Hi, > I agree which is why I am interested in the doubleflashers to begin with. > > Since the Aeroflash is a weaker flash "on paper" (which I can'f find on > the internet anymore), I am wondering if someone has found any info on the > double flash version's lumens/joules/subjective viewing/whatever to do > some kind of rough compare to see if it was much weaker "on paper" than > the single flash version. The problem is I can't find the detailed info on > their 152-0007 or their 152-0011 power supplys. I used to be able to. It > doesn't appear to be on their web site anymore. Maybe someone who bought > them has the info. > > -------------- Original message -------------- > > -- AeroElectric-List message posted by: Robert McCallum > > > The question isn't so much one of "how intense is the flash" but one of > human biometrics. The human eye and brain react extremely well to > motion or suddenness (if that's a word) of an event. The single flash > strobe gets your attention that something is there. But where?? By the > time your brain has recognized the existence of the flash it's gone. > This is the reason companies like whelan have developed the multiflash > units. The first part of the flash gets your attention the subsequent > flash or flashes gives your brain time to home in on where it is. It's > much easier to see a moving aircraft than one that' s stationary against > it's backg > round for instance. Now suppose that lighting conditions, > glare, or visibility are such that the only thing you see of a plane is > the flash of the strobe. With a single flash it's moved before you can > zero in on the location. With "multiflash" you get to adjust your vision > on the second, third, or fourth part of the flash, thus being able to > locate the aircraft before it's moved to a new location until the next > flash sequence. MUCH easier and less stressfu, especially in marginal > conditions. Now don't you want your pride ands joy to be the one easy to > distinguish and pick out of the sky instead of the one where the other > guy is saying to himself " I know I saw something out there somewhere"? > > Bob McC > > lucky wrote: > > -- AeroElectric-List message posted by: luckymacy@comcast.net (lucky) > > Has anyone looked into the > single vs. double flash AEROFLASH > NAV/STROBE/POSITION LIGHT KITS and determined if the "intensity" is > measurably > less than the single flash? Just observing these lights in single flash > form vs > whelens in formation flight leaves my to personally believe that the > whelens > aren't worth any the extra $ for them but still people seem to pass up > these > kits often enough to go for the Whelens that I keep asking why... > > http://www.aircraftspruce.com/catalog/elpages/aerofllightkits.php > > Lucky > > > ============================================================= > ================================================== > > > ________________________________ Message 25 ____________________________________ Time: 11:19:27 AM PST US From: "Bill Schlatterer" Subject: AeroElectric-List: FW: Z13A - Basic question ? Help anyone? --> AeroElectric-List message posted by: "Bill Schlatterer" Using the Z13A diagram for use with a Vans 60 amp int reg. Ordered the contactors, etc. from B&C and Todd sent me a S811-1 ID starter contactor which apparently does not have provisions for a starter engaged light. It has the two large terminals and one small switch terminal. It also costs $40 as opposed to $26 for a S702-1 which does allow for the starter engaged light. Some confusion on my part. I think that on the Z13A: The starter contactor would be a S702-1 The Battery contactor would be a S701-1 and the OV disconnect is shown as a S701-1 Does this look correct? Wonder what/why they would have shipped me a S811-1? More costly and fewer features? I must be missing something here, what would it be? Experience level: first plane, read the book, read it again, still only know enough to keep tongue off positive terminal :o) Thanks Bill S 7a fuse/panel Maumelle, Arkansas ________________________________ Message 26 ____________________________________ Time: 11:27:28 AM PST US From: "Paul Messinger" Subject: Re: AeroElectric-List: Aeroflash double flash vs. Whelens --> AeroElectric-List message posted by: "Paul Messinger" Even experimental aircraft must meet the far requirements appropriate to flight. I went around and around with FAA and Aero Flash years ago as well as my Ins agent. If strobes are required for your flight then they must meet the Fars for angle of visibility and intensity. At the time Aero Flash did not. I have no info that Aero Flash ever increased the output to meet the requirements. The FAA position is its up to the pilot (not even the owner) to verify that all required equipment for the flight meets the Fars. Thus its not the DAR's responsibility when the acft is inspected to verify lighting that is proper its the builder. Later its who ever is flying the aircraft. The insurance CO position is if the accident was in any way related to sub standard strobes your insurance is void. Also at that time the FAA will take action against you and your pilots license. But there are lots of stories around about what I am saying is not correct as well as the one that says carrying a co pilot for part of the flight test is OK during the first 25-40 hours. Ask the right FAA person and you will find out there are no cases where passengers of any type are allowed. Dittos for the strobe intensity. If you can find a commercial strobe with the right power output its fine for experimental use. Paul ----- Original Message ----- From: "Bob Black" Subject: RE: AeroElectric-List: Aeroflash double flash vs. Whelens > --> AeroElectric-List message posted by: "Bob Black" > > Like some other builders (see http://www.rv7.us/daily040908%20w.htm - this > site has a sequence of strobes and position lights) I'm using emergency > vehicle systems that put out just as much brightness and allow you to tailor > the flash sequence to what you want. You need to build or buy separate > position lights if you want to do that. I have priced these systems and > they seem to cost less than half of what the aviation stuff costs. What are > the downsides? > > Bob > Rv7 wings > > > -----Original Message----- > From: owner-aeroelectric-list-server@matronics.com > [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of lucky > To: aeroelectric-list@matronics.com > Subject: AeroElectric-List: Aeroflash double flash vs. Whelens > > --> AeroElectric-List message posted by: luckymacy@comcast.net (lucky) > > Has anyone looked into the single vs. double flash AEROFLASH > NAV/STROBE/POSITION LIGHT KITS and determined if the "intensity" is > measurably less than the single flash? Just observing these lights in > single flash form vs whelens in formation flight leaves my to personally > believe that the whelens aren't worth any the extra $ for them but still > people seem to pass up these kits often enough to go for the Whelens that I > keep asking why... > > http://www.aircraftspruce.com/catalog/elpages/aerofllightkits.php > > Lucky > -------------- Original message -------------- > > > --> AeroElectric-List message posted by: j1j2h3@juno.com > > > > > > In looking at strobe power supplies, all of those at Strobesnmore.com are > > rated in watts. However, the requirements for strobe lights are usually > > given in joules. How does one make the calculation to determine whether > > the output is sufficient? I know that one joule is equal to one > > watt-second, but I don't know how to handle the time factor. I suspect > > it has to do with flash duration and flashes per minute, but I haven't > > seen these numbers published for the equipment I've looked at. > > > > > > Jim Hasper - RV-7 > > Franklin, TN > > > > Do not archive > > > > > > > > > > > > > > Has anyone looked into the single vs. double flash AEROFLASH > NAV/STROBE/POSITION LIGHT KITS and determined if the "intensity" is > measurably less than the single flash? Just observing these lights in single > flash form vs whelens in formation flight leaves my to personally believe > that the whelens aren't worth any the extra $ for them but still people seem > to pass up these kits often enough to go for the Whelens that I keep asking > why... > > http://www.aircraftspruce.com/catalog/elpages/aerofllightkits.php > > Lucky > -------------- Original message -------------- > > -- AeroElectric-List message posted by: j1j2h3@juno.com > > > In looking at strobe power supplies, all of those at Strobesnmore.com are > rated in watts. However, the requirements for strobe lights are usually > given in joules. How does one make the calculation to determine whether > the output is sufficient? I know that one joule is equal to one > watt-second, but I don't know how to handle the time factor. I suspect > it has to do with flash duration and flashes per minute, but I haven't > seen these numbers published for the equipment I've looked at. > > > Jim Hasper - RV-7 > Franklin, TN > > Do not archive > > > The AeroElectric-List Email Forum - > /www.matronics.com/aeroelectric-list > > ________________________________ Message 27 ____________________________________ Time: 11:58:32 AM PST US From: "Paul Messinger" Subject: Re: AeroElectric-List: Re: Load dump comments clamav-milter version 0.80j on juliet.albedo.net --> AeroElectric-List message posted by: "Paul Messinger" The huge current loop during a shorting crowbar event generates a large magnetic field that can magnetize steel and mess up your compass calibration. I got 400 amps with longer that likely wires. When I simulated my aircraft wiring I got over 700 amps. Measurements were made with calibrated equipment. as well as being repeatable. If this does not bother you, be my guest. Paul > Sure that sounds scary but I'll wait for the report before getting > concerned. With 6 feet of 18awg wire in series with a C/B, an SCR, and > several connections it may be possible to get a couple of hundred amps > of instantaneous current flowing but so what? It is drawing down the > voltage which is what we want. > > The interesting thing to me is a nuisance trip. It sounds like it is > possible to ramp up the alternator output during the delay (40 ms?) > waiting for the OV contactor to open. However I haven't seen any reason > to be concerned about that yet and I will await the report. ________________________________ Message 28 ____________________________________ Time: 11:58:32 AM PST US From: "Paul Messinger" Subject: Re: AeroElectric-List: LOAD dump comments --> AeroElectric-List message posted by: "Paul Messinger" The use of a dead short crowbar is an application I, nor any of my associates, ever came across during our careers. Lots of shorting crow bars but NEVER across a battery. They were used widely across electrical power supplies where the energy being shorted was small compared to a modern battery. The power supply was designed to have a crow bar included and thus never produces huge currents in the process of shutting down. ALL inductors have load dumps when they are unloaded. The contactors we all use have enough stored energy to fire a spark plug when they are disconnected. This is contained with the diode across the coil. It increases the internal load dump from a couple of ms to around 40 ms. The dump current in this case is one amp. Both internal and external regulators generate load dumps that must be suppressed. Eric has one part of the solution which is his non shorting OVP. This gracefully disconnects if there is a long term OV vs a load dump. The load dump transorb across the alternator only protects the alternator, not the rest of the system and then only from alternator load dumps. We still need protection from buss spikes from where ever. Bob has said they are like snipe hunting, never to be found. Well my forth coming report has scope pix of these spikes I went on a snipe hunt and bagged a few! Another of Eric's transorb units on the bus will work but also consider a few transorbs in the non packages form across each bus. The end of the report will include our recommendation for better transient / load dump design. Paul ----- Original Message ----- From: "D Fritz" Subject: Re: AeroElectric-List: LOAD dump comments > --> AeroElectric-List message posted by: D Fritz > > "Thus the Crowbar OVP action not only shorts the buss it creates a load dump, > neither action is desirable or necessary. OVP protection does not need to be > crowbar in nature and surely not a unlimited current short." > > In reading the above, it sounds like we should be looking at another method of overvoltage protection, am I understanding this correctly? Does anyone have suggested architectures? Is this load dump only an issue with internally regulated alternators, or do externally regulated alternators just have protection already built in? In another thread, Gary raises the question of why we don't just attach the alternator directly to the battery (vice through the main contactor) to mitigate the load dump issue, any comments out there on why we should or should not do this? > > Dan Fritz > > > --------------------------------- > > ________________________________ Message 29 ____________________________________ Time: 12:01:41 PM PST US From: luckymacy@comcast.net (lucky) Subject: Re: AeroElectric-List: Aeroflash double flash vs. Whelens --> AeroElectric-List message posted by: luckymacy@comcast.net (lucky) Where/when/by who was the data collected that demonstrated that? -------------- Original message -------------- > --> AeroElectric-List message posted by: "Scott Jackson" > > > Has Aeroflash changed their power supplies? The reason I didn't install > Aeroflash-although the price was attractive-was the surging that its power > supply would induce in the electrical system, according to " The Electric > Connection" manual. > Scott in VAncouver > 165 hrs on RV-6 > police-car strobe power supply, Whelen heads > ----- Original Message ----- > From: "lucky" > To: > Subject: Re: AeroElectric-List: Aeroflash double flash vs. Whelens > > > > --> AeroElectric-List message posted by: luckymacy@comcast.net (lucky) > > > > Hi, > > I agree which is why I am interested in the doubleflashers to begin with. > > > > Since the Aeroflash is a weaker flash "on paper" (which I can'f find on > > the internet anymore), I am wondering if someone has found any info on the > > double flash version's lumens/joules/subjective viewing/whatever to do > > some kind of rough compare to see if it was much weaker "on paper" than > > the single flash version. The problem is I can't find the detailed info > > on their 152-0007 or their 152-0011 power supplys. I used to be able to. > > It doesn't appear to be on their web site anymore. Maybe someone who > > bought them has the info. > > > > -------------- Original message -------------- > > > >> --> AeroElectric-List message posted by: Robert McCallum > >> > >> > >> The question isn't so much one of "how intense is the flash" but one of > >> human biometrics. The human eye and brain react extremely well to > >> motion or suddenness (if that's a word) of an event. The single flash > >> strobe gets your attention that something is there. But where?? By the > >> time your brain has recognized the existence of the flash it's gone. > >> This is the reason companies like whelan have developed the multiflash > >> units. The first part of the flash gets your attention the subsequent > >> flash or flashes gives your brain time to home in on where it is. It's > >> much easier to see a moving aircraft than one that' s stationary against > >> it's background for instance. Now suppose that lighting conditions, > >> glare, or visibility are such that the only thing you see of a plane is > >> the flash of the strobe. With a single flash it's moved before you can > >> zero in on the location. With "multiflash" you get to adjust your vision > >> on the second, third, or fourth part of the flash, thus being able to > >> locate the aircraft before it's moved to a new location until the next > >> flash sequence. MUCH easier and less stressfu, especially in marginal > >> conditions. Now don't you want your pride ands joy to be the one easy to > >> distinguish and pick out of the sky instead of the one where the other > >> guy is saying to himself " I know I saw something out there somewhere"? > >> > >> Bob McC > >> > >> lucky wrote: > >> > >> >--> AeroElectric-List message posted by: luckymacy@comcast.net (lucky) > >> > > >> >Has anyone looked into the single vs. double flash AEROFLASH > >> NAV/STROBE/POSITION LIGHT KITS and determined if the "intensity" is > >> measurably > >> less than the single flash? Just observing these lights in single flash > >> form vs > >> whelens in formation flight leaves my to personally believe that the > >> whelens > >> aren't worth any the extra $ for them but still people seem to pass up > >> these > >> kits often enough to go for the Whelens that I keep asking why... > >> > > >> >http://www.aircraftspruce.com/catalog/elpages/aerofllightkits.php > >> > > >> >Lucky > >> > > >> > > >> > >> > >> > >> > >> > >> > > > > Hi, > > I agree which is why I am interested in the doubleflashers to begin with. > > > > Since the Aeroflash is a weaker flash "on paper" (which I can'f find on > > the internet anymore), I am wondering if someone has found any info on the > > double flash version's lumens/joules/subjective viewing/whatever to do > > some kind of rough compare to see if it was much weaker "on paper" than > > the single flash version. The problem is I can't find the detailed info on > > their 152-0007 or their 152-0011 power supplys. I used to be able to. It > > doesn't appear to be on their web site anymore. Maybe someone who bought > > them has the info. > > > > -------------- Original message -------------- > > > > -- AeroElectric-List message posted by: Robert McCallum > > > > > > The question isn't so much one of "how intense is the flash" but one of > > human biometrics. The human eye and brain react extremely well to > > motion or suddenness (if that's a word) of an event. The single flash > > strobe gets your attention that something is there. But where?? By the > > time your brain has recognized the existence of the flash it's gone. > > This is the reason companies like whelan have developed the multiflash > > units. The first part of the flash gets your attention the subsequent > > flash or flashes gives your brain time to home in on where it is. It's > > much easier to see a moving aircraft than one that' s stationary against > > it's backg > > round for instance. Now suppose that lighting conditions, > > glare, or visibility are such that the only thing you see of a plane is > > the flash of the strobe. With a single flash it's moved before you can > > zero in on the location. With "multiflash" you get to adjust your vision > > on the second, third, or fourth part of the flash, thus being able to > > locate the aircraft before it's moved to a new location until the next > > flash sequence. MUCH easier and less stressfu, especially in marginal > > conditions. Now don't you want your pride ands joy to be the one easy to > > distinguish and pick out of the sky instead of the one where the other > > guy is saying to himself " I know I saw something out there somewhere"? > > > > Bob McC > > > > lucky wrote: > > > > -- AeroElectric-List message posted by: luckymacy@comcast.net (lucky) > > > > Has anyone looked into the > > single vs. double flash AEROFLASH > > NAV/STROBE/POSITION LIGHT KITS and determined if the "intensity" is > > measurably > > less than the single flash? Just observing these lights in single flash > > form vs > > whelens in formation flight leaves my to personally believe that the > > whelens > > aren't worth any the extra $ for them but still people seem to pass up > > these > > kits often enough to go for the Whelens that I keep asking why... > > > > http://www.aircraftspruce.com/catalog/elpages/aerofllightkits.php > > > > Lucky > > > > > > ============================================================= > > ================================================== > > > > > > > > > > > > Where/when/by who was the data collected that demonstrated that? -------------- Original message -------------- -- AeroElectric-List message posted by: "Scott Jackson" Has Aeroflash changed their power supplies? The reason I didn't install Aeroflash-although the price was attractive-was the surging that its power supply would induce in the electrical system, according to " The Electric Connection" manual. Scott in VAncouver 165 hrs on RV-6 police-car strobe power supply, Whelen heads ----- Original Message ----- From: "lucky" To: Subject: Re: AeroElectric-List: Aeroflash double flash vs. Whelens -- AeroElectric-List message posted by: luckymacy@comcast.net (lucky) Hi, > ; I agree which is why I am interested in the doubleflashers to begin with. Since the Aeroflash is a weaker flash "on paper" (which I can'f find on the internet anymore), I am wondering if someone has found any info on the double flash version's lumens/joules/subjective viewing/whatever to do some kind of rough compare to see if it was much weaker "on paper" than the single flash version. The problem is I can't find the detailed info on their 152-0007 or their 152-0011 power supplys. I used to be able to. It doesn't appear to be on their web site anymore. Maybe someone who bought them has the info. -------------- Original message -------------- -- AeroElectric-List message posted by: Robert McCallum The question isn't so much one of "h ow intense is the flash" but one of human biometrics. The human eye and brain react extremely well to motion or suddenness (if that's a word) of an event. The single flash strobe gets your attention that something is there. But where?? By the time your brain has recognized the existence of the flash it's gone. This is the reason companies like whelan have developed the multiflash units. The first part of the flash gets your attention the subsequent flash or flashes gives your brain time to home in on where it is. It's much easier to see a moving aircraft than one that' s stationary against it's background for instance. Now suppose that lighting conditions, glare, or visibility are such that the only thing you see of a plane is the flash of the strobe. With a single flash it's move d before you can zero in on the location. With "multiflash" you get to adjust your vision on the second, third, or fourth part of the flash, thus being able to locate the aircraft before it's moved to a new location until the next flash sequence. MUCH easier and less stressfu, especially in marginal conditions. Now don't you want your pride ands joy to be the one easy to distinguish and pick out of the sky instead of the one where the other guy is saying to himself " I know I saw something out there somewhere"? Bob McC lucky wrote: -- AeroElectric-List message posted by: luckymacy@comcast.net (lucky) Has anyone looked into the single vs. double flash AEROFLASH NAV/STROBE/POSI TION LIGHT KITS and determined if the "intensity" is measurably less than the single flash? Just observing these lights in single flash form vs whelens in formation flight leaves my to personally believe that the whelens aren't worth any the extra $ for them but still people seem to pass up these kits often enough to go for the Whelens that I keep asking why... http://www.aircraftspruce.com/catalog/elpages/aerofllightkits.php Lucky Hi, I agree which is why I am interested in the doubleflashers to begin with. Since the Aerofla sh is a weaker flash "on paper" (which I can'f find on the internet anymore), I am wondering if someone has found any info on the double flash version's lumens/joules/subjective viewing/whatever to do some kind of rough compare to see if it was much weaker "on paper" than the single flash version. The problem is I can't find the detailed info on their 152-0007 or their 152-0011 power supplys. I used to be able to. It doesn't appear to be on their web site anymore. Maybe someone who bought them has the info. -------------- Original message -------------- -- AeroElectric-List message posted by: Robert McCallum The question isn't so much one of "how intense is the flash" but one of human biometrics. The human eye and brain react extremely we ll to motion or suddenness (if that's a word) of an event. The single flash strobe gets your attention that something is there. But where?? By the time your brain has recognized the existence of the flash it's gone. This is the reason companies like whelan have developed the multiflash units. The first part of the flash gets your attention the subsequent flash or flashes gives your brain time to home in on where it is. It's much easier to see a moving aircraft than one that' s stationary against it's backg round for instance. Now suppose that lighting conditions, glare, or visibility are such that the only thing you see of a plane is the flash of the strobe. With a single flash it's moved before you can zero in on the location. With "multiflash" you get to adjust your vision on the second, third, or fourth part of the flash, thus being able to locate the aircraft before it's moved to a new location until the next flash sequence. MUCH easier and less stressfu, especially in marginal conditions. Now don't you want your pride ands joy to be the one easy to distinguish and pick out of the sky instead of the one where the other guy is saying to himself " I know I saw something out there somewhere"? Bob McC lucky wrote: -- AeroElectric-List message posted by: luckymacy@comcast.net (lucky) Has anyone looked into the single vs. double flash AEROFLASH NAV/STROBE/POSITION LIGHT KITS and determined if the "intensity" is measurably less than the single flash? Just observing these lights in single flash form vs whelen s in formation flight leaves my to personally believe that the whelens aren't worth any the extra $ for them but still people seem to pass up these kits often enough to go for the Whelens that I keep asking why... http://www.aircraftspruce.com/catalog/elpages/aerofllightkits.php Lucky ============================================================= ================================================== ========================================================== =============================================== ________________________________ Message 30 ____________________________________ Time: 12:18:04 PM PST US From: "Paul Messinger" Subject: AeroElectric-List: Load dump and shutdown procedures --> AeroElectric-List message posted by: "Paul Messinger" With all the discussion on load dump ever wondered why now and not 50 years ago? One reason is then (and now) I have learned and then taught that the alternator was turned on only after the engine was started and both the battery and the alternator was only turned off AFTER the engine was completely stopped. Recently I have seem and observed first hand cases where the ammeter was checked during runup by turning the alternator off. Also the alternator and master were turned off before shutting down the engine. The latter procedure assures load dump and the former prevents load dump. Any one know when the latter procedure became popular in some circles??? The above does not include emergency or failure conditions. Paul ________________________________ Message 31 ____________________________________ Time: 12:18:04 PM PST US From: "Paul Messinger" Subject: Re: AeroElectric-List: Re: Load dump comments --> AeroElectric-List message posted by: "Paul Messinger" NOT true exactly. ANY inductor carrying current, rotating or not, power generating or power using, will try to continue the circulating current if the load or power source is disconnected. The magnitude of the load dump is related to the current being reduced. Clearly in the case of the alternator where 10-50 amps are being disconnected the effect is different when compared to the coil of a contactor where the current is one amp. Everyone knows that relay coils need suppression diodes. Well the same goes for alternators just much bigger diodes for the higher current. Also in the case of alternators or other power producing components the cure is different. Relay coils need the diode connected so its out of the circuit except when needed to continue the circulation current. Alternators need a voltage clamp to prevent excessive voltage during a sudden current reduction. We ignore load dumps from alternators in the normal electrical system as the battery acts like a current absorber and stabilizes the voltage. But if the battery is off line then the voltage increases until the remaining load can accept the current transient. If you disconnect an internally regulated alternator when it is producing output current the current has no where to go and the result is a voltage spike internal to the alternator. MOST internally regulated alternators have a load dump diode built in that will protect the alternator regulator under worst case conditions. Some have suggested that the rebuilt alternators sold by Vans are not properly protected. While this is an easy finger to point I have not seen any real investigation to prove this. Then there is the case of externally regulated alternators. The load dump is the same but in this case the system bus is still connected so it will see an overvoltage that may or may not damage equipment. If the alternator "B" lead is disconnected in this externally regulated alternator the internal load dump can produce a very hi voltage as there is nothing to clamp it other than the rectifier diodes in the alternator and they usually are heavy enough to prevent failure and they break down around 200V. > Load dump is an issue with any source of power that uses a rotating > conductor in a magnetic field. By the way, overvoltage and load dump are > related in that they both have associated overvoltages. Load dump is a > strictly transient OV condition caused by disconnecting a load, but an > overvoltage condition can be caused by a failed regulator or other causes > and may be long term. >Both need to be addressed. TRUE Paul ________________________________ Message 32 ____________________________________ Time: 12:36:03 PM PST US From: Kevin Horton Subject: Re: AeroElectric-List: Re: Load dump comments --> AeroElectric-List message posted by: Kevin Horton I'm interested as to which two items the crowbar was shorting when these large currents were measured. I'm assuming this is a different application than the crowbar OV protection that Bod espouses, where the crowbar shorts out the field circuit, popping a 5A CB. I can't imagine how 400 to 700 amps could be generated in the field circuit before the 5A CB popped. Are CBs that slow to trip? Or, was this a different application of a crowbar? Kevin Horton >--> AeroElectric-List message posted by: "Paul Messinger" > >The huge current loop during a shorting crowbar event generates a large >magnetic field that can magnetize steel and mess up your compass >calibration. > >I got 400 amps with longer that likely wires. When I simulated my aircraft >wiring I got over 700 amps. > >Measurements were made with calibrated equipment. as well as being >repeatable. > >If this does not bother you, be my guest. > >Paul > > >> Sure that sounds scary but I'll wait for the report before getting >> concerned. With 6 feet of 18awg wire in series with a C/B, an SCR, and >> several connections it may be possible to get a couple of hundred amps >> of instantaneous current flowing but so what? It is drawing down the >> voltage which is what we want. >> >> The interesting thing to me is a nuisance trip. It sounds like it is >> possible to ramp up the alternator output during the delay (40 ms?) >> waiting for the OV contactor to open. However I haven't seen any reason > > to be concerned about that yet and I will await the report. ________________________________ Message 33 ____________________________________ Time: 12:40:46 PM PST US From: luckymacy@comcast.net (lucky) Subject: Re: AeroElectric-List: Aeroflash double flash vs. Whelens --> AeroElectric-List message posted by: luckymacy@comcast.net (lucky) You must have gotten snookered and didn't do your homework or something because the 152-0007 and 152-0011 power supplies have been approved and are used on certified aircraft. Visit Their web site for more info on their FAA approval list. do not archive lucky -------------- Original message -------------- > --> AeroElectric-List message posted by: "Paul Messinger" > > Even experimental aircraft must meet the far requirements appropriate to > flight. > > I went around and around with FAA and Aero Flash years ago as well as my Ins > agent. > > If strobes are required for your flight then they must meet the Fars for > angle of visibility and intensity. At the time Aero Flash did not. I have no > info that Aero Flash ever increased the output to meet the requirements. > > The FAA position is its up to the pilot (not even the owner) to verify that > all required equipment for the flight meets the Fars. Thus its not the DAR's > responsibility when the acft is inspected to verify lighting that is proper > its the builder. Later its who ever is flying the aircraft. > > The insurance CO position is if the accident was in any way related to sub > standard strobes your insurance is void. Also at that time the FAA will take > action against you and your pilots license. > > But there are lots of stories around about what I am saying is not correct > as well as the one that says carrying a co pilot for part of the flight test > is OK during the first 25-40 hours. Ask the right FAA person and you will > find out there are no cases where passengers of any type are allowed. Dittos > for the strobe intensity. > > If you can find a commercial strobe with the right power output its fine for > experimental use. > > Paul > > ----- Original Message ----- > From: "Bob Black" > To: > Subject: RE: AeroElectric-List: Aeroflash double flash vs. Whelens > > > > --> AeroElectric-List message posted by: "Bob Black" > > > > Like some other builders (see http://www.rv7.us/daily040908%20w.htm - this > > site has a sequence of strobes and position lights) I'm using emergency > > vehicle systems that put out just as much brightness and allow you to > tailor > > the flash sequence to what you want. You need to build or buy separate > > position lights if you want to do that. I have priced these systems and > > they seem to cost less than half of what the aviation stuff costs. What > are > > the downsides? > > > > Bob > > Rv7 wings > > > > > > -----Original Message----- > > From: owner-aeroelectric-list-server@matronics.com > > [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of lucky > > To: aeroelectric-list@matronics.com > > Subject: AeroElectric-List: Aeroflash double flash vs. Whelens > > > > --> AeroElectric-List message posted by: luckymacy@comcast.net (lucky) > > > > Has anyone looked into the single vs. double flash AEROFLASH > > NAV/STROBE/POSITION LIGHT KITS and determined if the "intensity" is > > measurably less than the single flash? Just observing these lights in > > single flash form vs whelens in formation flight leaves my to personally > > believe that the whelens aren't worth any the extra $ for them but still > > people seem to pass up these kits often enough to go for the Whelens that > I > > keep asking why... > > > > http://www.aircraftspruce.com/catalog/elpages/aerofllightkits.php > > > > Lucky > > -------------- Original message -------------- > > > > > --> AeroElectric-List message posted by: j1j2h3@juno.com > > > > > > > > > In looking at strobe power supplies, all of those at Strobesnmore.com > are > > > rated in watts. However, the requirements for strobe lights are usually > > > given in joules. How does one make the calculation to determine whether > > > the output is sufficient? I know that one joule is equal to one > > > watt-second, but I don't know how to handle the time factor. I suspect > > > it has to do with flash duration and flashes per minute, but I haven't > > > seen these numbers published for the equipment I've looked at. > > > > > > > > > Jim Hasper - RV-7 > > > Franklin, TN > > > > > > Do not archive > > > > > > > > > > > > > > > > > > > > > > Has anyone looked into the single vs. double flash AEROFLASH > > NAV/STROBE/POSITION LIGHT KITS and determined if the "intensity" is > > measurably less than the single flash? Just observing these lights in > single > > flash form vs whelens in formation flight leaves my to personally believe > > that the whelens aren't worth any the extra $ for them but still people > seem > > to pass up these kits often enough to go for the Whelens that I keep > asking > > why... > > > > http://www.aircraftspruce.com/catalog/elpages/aerofllightkits.php > > > > Lucky > > -------------- Original message -------------- > > > > -- AeroElectric-List message posted by: j1j2h3@juno.com > > > > > > In looking at strobe power supplies, all of those at Strobesnmore.com are > > rated in watts. However, the requirements for strobe lights are usually > > given in joules. How does one make the calculation to determine whether > > the output is sufficient? I know that one joule is equal to one > > watt-second, but I don't know how to handle the time factor. I suspect > > it has to do with flash duration and flashes per minute, but I haven't > > seen these numbers published for the equipment I've looked at. > > > > > > Jim Hasper - RV-7 > > Franklin, TN > > > > Do not archive > > > > > > The AeroElectric-List Email Forum - > > /www.matronics.com/aeroelectric-list > > > > > > > > > > You must have gotten snookered and didn't do your homework or something because the 152-0007 and 152-0011 power supplies have been approved and are used on certified aircraft. Visit Their web site for more info on their FAA approval list. do not archive lucky -------------- Original message -------------- -- AeroElectric-List message posted by: "Paul Messinger" Even experimental aircraft must meet the far requirements appropriate to flight. I went around and around with FAA and Aero Flash years ago as well as my Ins agent. If strobes are required for your flight then they must meet the Fars for angle of visibility and intensity. At the time Aero Flash did not. I have no info that Aero Flash ever increased the output to meet the requirements. The FAA position is its up to the pilot (not even the owner) to verify that all required equipment for the flight meets the Fars. Thus its not the DAR's responsibility when the acft is inspected to verify lighting that is proper its the bui lder. Later its who ever is flying the aircraft. The insurance CO position is if the accident was in any way related to sub standard strobes your insurance is void. Also at that time the FAA will take action against you and your pilots license. But there are lots of stories around about what I am saying is not correct as well as the one that says carrying a co pilot for part of the flight test is OK during the first 25-40 hours. Ask the right FAA person and you will find out there are no cases where passengers of any type are allowed. Dittos for the strobe intensity. If you can find a commercial strobe with the right power output its fine for experimental use. Paul ----- Original Message ----- From: "Bob Black" To: Subject: RE: AeroElectric-List: Aerof lash double flash vs. Whelens -- AeroElectric-List message posted by: "Bob Black" Like some other builders (see http://www.rv7.us/daily040908%20w.htm - this site has a sequence of strobes and position lights) I'm using emergency vehicle systems that put out just as much brightness and allow you to tailor the flash sequence to what you want. You need to build or buy separate position lights if you want to do that. I have priced these systems and they seem to cost less than half of what the aviation stuff costs. What are the downsides? Bob Rv7 wings -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf O f lucky To: aeroelectric-list@matronics.com Subject: AeroElectric-List: Aeroflash double flash vs. Whelens -- AeroElectric-List message posted by: luckymacy@comcast.net (lucky) Has anyone looked into the single vs. double flash AEROFLASH NAV/STROBE/POSITION LIGHT KITS and determined if the "intensity" is measurably less than the single flash? Just observing these lights in single flash form vs whelens in formation flight leaves my to personally believe that the whelens aren't worth any the extra $ for them but still people seem to pass up these kits often enough to go for the Whelens that I keep asking why... http://www.aircraftspruce.com/catalog/elpages/aerofllightkits.php Lucky -------------- Original message -------------- -- AeroElectric-List message posted by: j1j2h3@juno.com In looking at strobe power supplies, all of those at Strobesnmore.com are rated in watts. However, the requirements for strobe lights are usually given in joules. How does one make the calculation to determine whether the output is sufficient? I know that one joule is equal to one watt-second, but I don't know how to handle the time factor. I suspect it has to do with flash duration and flashes per minute, but I haven't seen these numbers published for the equipment I've looked at. Jim Hasper - RV-7 Franklin, TN Do not archive Has anyone looked into the single vs. double flash AEROFLASH NAV/STROBE/POSITION LIGHT KITS and determined if the "intensity" is measurably less than the single flash? Just observing these lights in single flash form vs whelens in formation flight leaves my to personally believe that the whelens aren't worth any the extra $ for them but still people seem to pass up these kits often enough to go for the Whelens that I keep asking why... http://www.aircraftspruce.com/catalog/elpages/aerofllightkits.php Lucky -------------- Original message -------------- -- AeroElectric-List message posted by: j1j2h3@juno.com In looking at strobe power supplies, all of those at Strobesnmore.com are rated in watts. However, the requirements for strobe lights are usually given in joules. How does one make the calculation to determine whether the output is sufficient? I know that one joule is equal to one watt-second, but I don't know how to handle the time factor. I suspect it has to do with flash duration and flashes per minute, but I haven't seen these numbers published for the equipment I've looked at. Jim Hasper - RV-7 Franklin, TN Do not archive The AeroElectric-List Email Forum - /www.matronics.com/aeroelectric-list red entirely through the Contributions /www.matronics.com/emaillists ________________________________ Message 34 ____________________________________ Time: 12:58:36 PM PST US From: "Paul Messinger" Subject: Re: AeroElectric-List: Re: Load dump comments --> AeroElectric-List message posted by: "Paul Messinger" Its wired exactly as Bob shows. The power path is thru the CB that powers the relay (in the case of a "B" lead the contactor) and the crow bar shorts the CB to ground and the 400 amps is thru the wiring and thru the CB and OVP SCR. There is no HI current thru the field. Draw a wire from the load side of the CB to ground (thats the OVP). The resulting circuit is the battery to the CB to the OVP to ground. The OVP tripps and its scr shorts the OVP to ground. Net result is the CB is directly across the battery plus wiring. The modern battery will provide more than 1000 amps (some closer to 2000 amps) across the CB with very short leads. One solution is a 1/8 to 1/2 ohm resistor in the OVP shorting path to limit current and still blow the CB. I got 730 amps with shorter but realistic leads and the Powersonic 12v18ah battery that Bob promotes. Far cry from a Gill flooded cell acft battery. I tried 3 different popular 5 amp CB brands and all showed at least 50 ms to open. (and that is when they are warmed up). After a couple of hours at rest the CB can take more than 80MS to trip. Yes they are that slow. Paul ----- Original Message ----- From: "Kevin Horton" Subject: Re: AeroElectric-List: Re: Load dump comments > --> AeroElectric-List message posted by: Kevin Horton > > I'm interested as to which two items the crowbar was shorting when > these large currents were measured. I'm assuming this is a different > application than the crowbar OV protection that Bod espouses, where > the crowbar shorts out the field circuit, popping a 5A CB. I can't > imagine how 400 to 700 amps could be generated in the field circuit > before the 5A CB popped. Are CBs that slow to trip? Or, was this a > different application of a crowbar? > > Kevin Horton > > >--> AeroElectric-List message posted by: "Paul Messinger" > > > >The huge current loop during a shorting crowbar event generates a large > >magnetic field that can magnetize steel and mess up your compass > >calibration. > > > >I got 400 amps with longer that likely wires. When I simulated my aircraft > >wiring I got over 700 amps. > > > >Measurements were made with calibrated equipment. as well as being > >repeatable. > > > >If this does not bother you, be my guest. > > > >Paul > > > > > >> Sure that sounds scary but I'll wait for the report before getting > >> concerned. With 6 feet of 18awg wire in series with a C/B, an SCR, and > >> several connections it may be possible to get a couple of hundred amps > >> of instantaneous current flowing but so what? It is drawing down the > >> voltage which is what we want. > >> > >> The interesting thing to me is a nuisance trip. It sounds like it is > >> possible to ramp up the alternator output during the delay (40 ms?) > >> waiting for the OV contactor to open. However I haven't seen any reason > > > to be concerned about that yet and I will await the report. > >