---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Thu 03/17/05: 33 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:16 AM - OV protection debate (Dan O'Brien) 2. 05:43 AM - Re: Re: White Paper on Crowbar OV Protection (Vern W.) 3. 05:43 AM - Re: OV protection debate (Robert L. Nuckolls, III) 4. 06:02 AM - Re: OV protection debate (Hans Teijgeler) 5. 06:09 AM - Re: OV protection debate (Chuck Jensen) 6. 06:38 AM - Re: White Paper on Crowbar OV Protection (Ken) 7. 06:38 AM - Re: Re: White Paper on Crowbar OV Protection (Ken) 8. 08:30 AM - Audio panel for single seat Yak (Dee L. Conger) 9. 09:45 AM - Re: OV protection debate (Mickey Coggins) 10. 10:01 AM - Re: Audio panel for single seat Yak (rv-9a-online) 11. 10:06 AM - Apollo SL40 (John Tvedte) 12. 10:32 AM - Re: Apollo SL40 (Walter Tondu) 13. 10:41 AM - Re: Audio panel for single seat Yak (James E. Clark) 14. 10:43 AM - Re: Audio panel for single seat Yak (Dee L. Conger) 15. 10:47 AM - Re: Apollo SL40 (Richard Tasker) 16. 12:26 PM - Re: OV protection debate (Fiveonepw@aol.com) 17. 12:29 PM - Re: Apollo SL40 (John Danielson) 18. 03:19 PM - Re: Audio panel for single seat Yak (rv-9a-online) 19. 03:49 PM - Re: Re: White Paper on Crowbar OV Protection (Andrew Rowley) 20. 04:26 PM - Re: White Paper on Crowbar OV Protection (Andrew Rowley) 21. 04:42 PM - Re: Using a 115 volt 400 hz device in a 12 volt airplane (Pat Hatch) 22. 05:03 PM - Re: White Paper on Crowbar OV Protection (Matt Prather) 23. 05:20 PM - Re: Audio panel for single seat Yak (james freeman) 24. 05:42 PM - Re: White Paper on Crowbar OV Protection (Andrew Rowley) 25. 05:59 PM - Re: White Paper on Crowbar OV Protection (Ken) 26. 06:04 PM - Re: Using a 115 volt 400 hz device in a 12 volt (Ken) 27. 06:08 PM - Re: White Paper on Crowbar OV Protection (Chuck Jensen) 28. 06:17 PM - Re: White Paper on Crowbar OV Protection (Matt Prather) 29. 06:18 PM - Re: Audio panel for single seat Yak (James Freeman) 30. 06:29 PM - Re: Audio panel for single seat Yak (Dee L. Conger) 31. 06:56 PM - Re: Using a 115 volt 400 hz device in a 12 (Robert L. Nuckolls, III) 32. 07:53 PM - Re: OV protection debate (Tim Olson) 33. 08:49 PM - Re: Audio panel for single seat Yak (James E. Clark) ________________________________ Message 1 _____________________________________ Time: 05:16:13 AM PST US From: "Dan O'Brien" Subject: AeroElectric-List: OV protection debate --> AeroElectric-List message posted by: "Dan O'Brien" In the OV protection debate, you engineers are losing your non-engineer OBAM readers. The problems are jargon, which is not easily deciphered by non-engineers, and abstractions for which the connection to the real world problem of building a reliable, failure tolerant system, is not immediately clear. It's too expensive for us non-engineers to spend the time trying to decipher the jargon and draw the connections. Is the audience here supposed to be physicists and electronics engineers, or the OBAM community (which consists of doctors, carpenters, lawyers, economists, mechanics, managers, burger flippers, etc.)? Many readers of this list won't benefit if the idea can't be made simple enough for OBAMers to translate into their projects. Just a comment, FWIW. ________________________________ Message 2 _____________________________________ Time: 05:43:29 AM PST US From: "Vern W." Subject: Re: AeroElectric-List: Re: White Paper on Crowbar OV Protection --> AeroElectric-List message posted by: "Vern W." Give 'em hell, Bob :-) One thing though: I AM interested in a follow up to where it was found (anecdotally for the moment) that alternators sold by Van's seem to fail when installed with the crowbar OV protection circuit and don't otherwise. If true, then something is obviously going on that needs to be looked at a bit closer. Any ideas on that? Vern ----- Original Message ----- From: "Robert L. Nuckolls, III Protection" Subject: Re: AeroElectric-List: Re: White Paper on Crowbar OV Protection > --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" Protection > > At 04:58 PM 3/16/2005 -0500, you wrote: > > >--> AeroElectric-List message posted by: "Eric M. Jones" > > > >Robert, et al. > > > >Re: > >http://www.aeroelectric.com/articles/Crobar_OV_Protection/Crowbar_White_Pap er.pdf > > > >About 5000 years ago the Chinese had remarkable scientific techniques. But > >somewhere along the way they decided that an experiment isolated from the > >rest of the world was simply not valid, because it was believed that > >everything influenced everything else. Ahem....but I digress........maybe. > > If the experiment is too complex, then the results are not repeatable > due to outside influences and does not illuminate a simple-idea. The > standard for the Coulomb (ampere-second) is defined in a manner > that anyone with the appropriate equipment can repeat the experiment > and obtain the same results. My wife is an expert at complex experiments > but it takes a really agile program to do statistical analysis on > data and to predict cause and effect with reasonable certainty. I'll > suggest we avoid statistics for this study and concentrate on the > repeatable physics. > > > >The White Paper skirts the key issue which is: Why bother using the crowbar > >technique when it has been abandoned by the rest of the entire cosmic > >universe for systems such as this? > > I haven't skirted anything. The white paper makes no recommendations > nor does it reflect anyone's opinions. > > > I have in my hand the data sheets for the > >MC3309X line of Motorola alternator voltage regulator chips (the most recent > >of which--MC33099-- contains adaptive logic!...but I digress). Can you guess > >what Motorola uses to terminate the field winding when bad things happen? > >There are about a hundred bazillion of these in service (and sampling the > >product stream to get one is like drinking from a firehose....but I > >digress). No crowbars here bubela. > > To my knowledge crowbar ov protection has never been used in > the automotive world. Further, as far as I know, I was the first > to introduce it to aviation when it was the ONLY system that would > qualify on the turbine Bonanza out of a field of several dozen > commonly available OV relays of the time. > > >Nobody argues that a crowbar works, it just isn't used anymore because > >better methods are available. For those who MUST have a crowbar do it this > >way: > >http://www.periheliondesign.com/downloads/NOOVP.pdf But unless the system > >requirement is to make the whole circuit dead in a wink, nobody does this > >anymore. > > > Haven't even addressed requirements yet. That's getting way ahead > of the study at hand. > > >Now to the White Paper: > > > >1) Cover page is okay except "Over Voltage" should be hyphenated. > >"...Comprised of..." is not English. > >2) What is this drawing? Nobody has an electrical system as shown. The > >Klixon 7274 is the way-fastest part in the series. > > The experiment is not intended to duplicate anyone's electrical > system. Is it your suggestion that the experiment be repeated with > another circuit breaker? 7274 series is all I have in my junk > box. You pick a number, I'll go find one. > > > What is the big diode? > > MCR69 SCR > > >Why not use the AE Crowbar here instead of whatever stand-in we see? [Insert > >eight-dozen other quibbles here.] > > The purpose of this experiment was to deduce exactly what the > measured data shows. Peak currents, delay times and influences on > bus voltage when subjected to those current. I mentioned > at the end of the paper that we'll go explore the dynamic characteristics > of the design under study. That's a separate experiment/analysis > and will probably use the full-up OVM-14 > > > > If RAC has a spare TDS210 in the closet > >I'd jeeze I'd love to have one. But I digress..... > > RAC doesn't own own as far as I know. It's part of my personally > owned professional tools. > > >3) Okay...short attention span. The rest of the report massages the figures > >a bit but arrives at the conclusion that maybe 263A or so blasts through the > >little 5A Klixon 7274 like a photon torpedo. > > Yes . . . so? If the 7274 were sitting on someone's aircraft breaker > panel and the downstream wire gets faulted, is there any guarantee > that the fault current won't be 263 or more or less? This isn't > germane to the discussion. > > You've missed the point of the paper. The "stand in" is indeed an > MCR69 device, exactly as used in several hundreds of OVM-14 modules > produced over the past 10 years or so. > > > >Discussion: The Klixon 7274 is not rated for 14.5 V trips of this magnitude. > > Perhaps you're privy to some limitations on the 7274 that I am not. > It's indeed rated at 28v which accounts for 95% of its application. > Where do we read that stresses for 14v operation depart markedly > from those cited for 28v. I can call the guys at Eaton/Cuttler-Hammer > tomorrow if we're needing any documentation. Can you enlighten me? > > >While it is rated as "Unlimited Amps at 28V", can we therefore assume that > >this makes 14.5V a piece of cake? Hardly; from 8-16 volts is a kind of > >neverland for electrical contacts---to high for gold and too low for > >silver--the voltages/trip characteristics do not scale. > > I wouldn't suggest that they do. Assuming that a builder does > use a 7274 Klixon in his system. What is the risk? Is the breaker > at risk of failing to open? Failing to re-close after an OV event? > Reduction in service life from the published 2500 cycles at > 30VDC resistive? If it were reduced to perhaps 100 cycles, should > I care? In any case, the experiment wasn't about breaker selection. > Pick another breaker and I'll go find one. > > > The TI/Klixon graphs > >show the maximum breaking capacity at 28V is 1000% (10X) rated and 0.10 to > >0.40 S. NOT 263/5= 5260% and 15 mS. Assuming we do this anyway--how many > >shots is the breaker now good for? 3? 10? 1000? Who knows? > > I assume nothing about the 7274. It's a breaker that came from > my junkbox to investigate the values measured and cited. If you > have other measurements you'd like to see, please state them > and the suggested test setup and I'll go see what I get. > > Again, you're missing the point of the experiment. I belive I've > read numbers cited that crowbar currents as high as 700 amps > have been measured. My question is: what was the setup so that > I might go to my workbench and measure those currents myself? > > I've read numbers citing time delays far longer than anything > I've seen in about 15 years of producing this system. I'm not > arguing with those numbers, only trying to deduce how they were > acquired. I've often suggested that the repeatable experiment > is the Holy Grail of quantification and understanding. To date, > I've seen lots of numbers which mystify me. Soooo . . . an hour > or so at the workbench produced the data cited to date. More > is yet to come. > > > >Discussion: The alternator shown....oops, who stole the darned alternator? > >The alternator does something very bad when crowbarred. It puffs up its > >little cheeks and chest preparing to spew out more electrons, but the next > >second, loadless, it is disappointed and does the Technicolor yawn off the > >back porch. This is my explanation for Load Dump which is better than > >Paul's, but I digress....The alternators contribution to the OVP episode is > >not strictly a DC matter. > > I believe I understand but I'm not convinced that my understanding > matches yours. We spoke of some testing to be done and data > to be shared but to date, pronouncements are made > on suitability or lack of suitability-to-task with little or > no foundation in repeatable experiments. I did a lot > of this same work 20 years ago for Beech and again 5 years later > for B&C. I'm repeating it again with the intent of laying out > exactly what I've done, the measurements I've acquired and > my interpretation of their significance. I've acquired an alternator > test stand and hope to pick it up next week sometime when my > son lets me have my truck back. > > > >Anyway, I suggest that the test setup in not a good representation of what > >is happening in the system. > > The test setup IS a representation of exactly what it shows and no more. > It describes a study and analysis of source impedances and current > limitations based on a choice of materials that would normally be > EXPECTED to produce the highest crowbar currents. Admittedly this > investigation > is a small part of the whole. But I find it useful to investigate one > feature at a time. Recall my penchant for boiling system operations > down to their rudimentary components . . . simple ideas that stand alone > and are easily understood and INVARIABLE. Then we'll start stacking > them together to see if the system performance is meeting objectives. > > > >Finally....whew....we get back to the main question---Why bother hammering > >the electrical system with a crowbar when you don't have to? Let's have some > >common sense. > > Define "hammer" . . . Please use quantified terminology. You seem to > object to deliberate development of a current pulse designed to open > a breaker under circumstances it is DESIGNED to handle. The experiment > thus far is intended to DEMONSTRATE that currents developed the typical > system are modest compared to values cited without benefit of a supporting > experiment. Further, they are deduced to not place any other part of the > system at risk in that bus voltage excursions are no worse than for > energizing a landing gear pump. It's was intended to INVESTIGATE the > elusive 700A pulse . . . or even a 300A pulse for that matter. The only > time I saw a crowbar event of 300A was on Bill's 24v test stand with > very atypical wiring lengths. The bench test setup I wrote about > demonstrated a crowbar event of less than 200 amps. > > > >With great respect...and sorry about the humor...it's those pills the doctor > >makes me take. > > Understand. Had to change my blood pressure medicine several times > before I found one I can live with and still does the job. My invitation > is to join in analysis of the data presented thus far. I'll be pleased to > explore the features cited in a manner that can be repeated by anyone else > at any time. This isn't a contest or an attempt to persuade anyone of > anything. Let's go get the data and understand the physics that drives it. > If you have suggestions to make for further testing in Phase I, I'd be > pleased to respond. After all the numbers are in, only then does anyone > have all the information needed to participate in their own decision making > process. > > Bob . . . > > ________________________________ Message 3 _____________________________________ Time: 05:43:29 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: OV protection debate --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 08:15 AM 3/17/2005 -0500, you wrote: >--> AeroElectric-List message posted by: "Dan O'Brien" > >In the OV protection debate, you engineers are losing your >non-engineer OBAM readers. The problems are jargon, which is not >easily deciphered by non-engineers, and abstractions for which the >connection to the real world problem of building a reliable, failure >tolerant system, is not immediately clear. It's too expensive for us >non-engineers to spend the time trying to decipher the jargon and draw >the connections. >Is the audience here supposed to be physicists and electronics >engineers, or the OBAM community (which consists of doctors, >carpenters, lawyers, economists, mechanics, managers, burger flippers, >etc.)? Many readers of this list won't benefit if the idea can't be >made simple enough for OBAMers to translate into their projects. I'm well aware that the vast majority of folks who visit here are MOST interested in knowing what parts to buy and how to wire them up. However, when debates are mounted in support of or against any particular technique or philosophy, it's of vital importance that those who offer opinions do so with a full and common understanding of the physics and philosophies being debated. Would you rather that parties interested in such conversation cloistered their efforts in hidden spaces until they're ready to emerge with conclusions? That's what our politicians do. That's what marketing folks who craft advertisements do. The LAST thing they want is for their target audience to understand what has transpired. >Just a comment, FWIW. Point well taken and acknowledged. The remedy is at hand. Please use your delete key as appropriate to your personal interests and needs for utilizing this list. Bob . . . ________________________________ Message 4 _____________________________________ Time: 06:02:02 AM PST US From: "Hans Teijgeler" Subject: RE: AeroElectric-List: OV protection debate --> AeroElectric-List message posted by: "Hans Teijgeler" Heck Dan, I AM a physicists and they have lost me! :-) Hans Do not archive > -----Oorspronkelijk bericht----- > Van: owner-aeroelectric-list-server@matronics.com [mailto:owner- > aeroelectric-list-server@matronics.com] Namens Dan O'Brien > Verzonden: donderdag 17 maart 2005 14:15 > Aan: AeroElectric-List@matronics.com > Onderwerp: AeroElectric-List: OV protection debate > > --> AeroElectric-List message posted by: "Dan O'Brien" > > > In the OV protection debate, you engineers are losing your > non-engineer OBAM readers. The problems are jargon, which is not > easily deciphered by non-engineers, and abstractions for which the > connection to the real world problem of building a reliable, failure > tolerant system, is not immediately clear. It's too expensive for us > non-engineers to spend the time trying to decipher the jargon and draw > the connections. > > Is the audience here supposed to be physicists and electronics > engineers, or the OBAM community (which consists of doctors, > carpenters, lawyers, economists, mechanics, managers, burger flippers, > etc.)? Many readers of this list won't benefit if the idea can't be > made simple enough for OBAMers to translate into their projects. > > Just a comment, FWIW. > > > > > ________________________________ Message 5 _____________________________________ Time: 06:09:44 AM PST US Subject: RE: AeroElectric-List: OV protection debate From: "Chuck Jensen" --> AeroElectric-List message posted by: "Chuck Jensen" Einstein suggested things should be made as simple as possible...but no simpler. I too, am seriously underwater on most of the detailed technical debate but one thing I do understand is that technical things can not always be discussed in simplistic terms that us commoners and pedestrian can grasp. However, we stand by to adopt the consensus results when its committed to a diagram and parts list. Chuck Do Not Archive -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Robert L. Nuckolls, III Subject: Re: AeroElectric-List: OV protection debate --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 08:15 AM 3/17/2005 -0500, you wrote: >--> AeroElectric-List message posted by: "Dan O'Brien" > >In the OV protection debate, you engineers are losing your >non-engineer OBAM readers. The problems are jargon, which is not >easily deciphered by non-engineers, and abstractions for which the >connection to the real world problem of building a reliable, failure >tolerant system, is not immediately clear. It's too expensive for us >non-engineers to spend the time trying to decipher the jargon and draw >the connections. >Is the audience here supposed to be physicists and electronics >engineers, or the OBAM community (which consists of doctors, >carpenters, lawyers, economists, mechanics, managers, burger flippers, >etc.)? Many readers of this list won't benefit if the idea can't be >made simple enough for OBAMers to translate into their projects. I'm well aware that the vast majority of folks who visit here are MOST interested in knowing what parts to buy and how to wire them up. However, when debates are mounted in support of or against any particular technique or philosophy, it's of vital importance that those who offer opinions do so with a full and common understanding of the physics and philosophies being debated. Would you rather that parties interested in such conversation cloistered their efforts in hidden spaces until they're ready to emerge with conclusions? That's what our politicians do. That's what marketing folks who craft advertisements do. The LAST thing they want is for their target audience to understand what has transpired. >Just a comment, FWIW. Point well taken and acknowledged. The remedy is at hand. Please use your delete key as appropriate to your personal interests and needs for utilizing this list. Bob . . . ________________________________ Message 6 _____________________________________ Time: 06:38:42 AM PST US From: Ken Subject: Re: AeroElectric-List: White Paper on Crowbar OV Protection --> AeroElectric-List message posted by: Ken Thank you Bob It is nice to see some numbers based on an understandable real experiment. I've got 22awg wire that is a bit longer with more connections and a 2 amp CB in my aircraft over voltage circuit and I'm very comfortable with it so far. I look forward to the next installment. Ken Robert L. Nuckolls, III wrote: >--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" > > >See: > >http://www.aeroelectric.com/articles/Crobar_OV_Protection/Crowbar_White_Paper.pdf > > > Bob . . . > > > ________________________________ Message 7 _____________________________________ Time: 06:38:42 AM PST US From: Ken Subject: Re: AeroElectric-List: Re: White Paper on Crowbar OV Protection --> AeroElectric-List message posted by: Ken Apparently they tell the control circuitry to shut off the Mosfet gate. http://www.ortodoxism.ro/datasheets/motorola/MC33092A.pdf Presumaby this is "state of the installed art" but it seems that there are still failure modes in the Mosfet (the switch that turns field current on and off) and the control circuitry that apparently render the load dump and over voltage control ineffective. It is nice to have an idea of what might be there, even if we can't quantify the risks or tell what is actually in a specific alternator. It would be nice to replace my B lead contactor with a solid state device but I need to see the numbers and test results, not just the theory, before I'm willing to consider replacing or eliminating the contactor. So far I'm still quite happy with the crowbar overvoltage protection but I'm following the discussion. Ken Eric M. Jones wrote: >-->snip > >I have in my hand the data sheets for the >MC3309X line of Motorola alternator voltage regulator chips (the most recent >of which--MC33099-- contains adaptive logic!...but I digress). Can you guess >what Motorola uses to terminate the field winding when bad things happen? > > ________________________________ Message 8 _____________________________________ Time: 08:30:06 AM PST US Subject: AeroElectric-List: Audio panel for single seat Yak From: "Dee L. Conger" --> AeroElectric-List message posted by: "Dee L. Conger" Hi Bob, I'm currently working on an electrical system for my Yak 50, which is a single seat Russian airplane. The plane will be equipped with an SL30 Nav/Com, an SL70 Transponder and a Blue Mountain EFIS sport - powered by a B&C pad-mounted alternator (for M14P). I'm not quite sure what to do about an audio panel - since I have only one Nav/Com, there doesn't seem to be a real need for one, expect for mixing in music and maybe for the marker beacon receiver. I plan on using a stereo headset and would like to be able to pipe in MP3s. Would your isolation amp be a good solution? Or, can you recommend a small, single place audio panel? Thanks, Dee L. Conger (858) 754-3010 Direct This email and any attachments thereto may contain private, confidential, and privileged material for the sole use of the intended recipient. Any review, copying, or distribution of this email (or any attachments thereto) by others is strictly prohibited. If you are not the intended recipient, please contact the sender immediately and permanently delete the original and any copies of this email and any attachments thereto. ________________________________ Message 9 _____________________________________ Time: 09:45:30 AM PST US From: Mickey Coggins Subject: Re: AeroElectric-List: OV protection debate --> AeroElectric-List message posted by: Mickey Coggins One of my favorite quotes. I used it a lot when I was slinging code in a previous life. Another one, when asked if it could get done faster if I had some help, was "Adding a second woman to the job won't make the baby come in 4.5 months." Please keep the debate going - I'm enjoying it, and learning things along the way. Mickey > Einstein suggested things should be made as simple as possible...but > no simpler. ... -- Mickey Coggins http://www.rv8.ch/ #82007 Wiring ________________________________ Message 10 ____________________________________ Time: 10:01:56 AM PST US From: rv-9a-online Subject: Re: AeroElectric-List: Audio panel for single seat Yak --> AeroElectric-List message posted by: rv-9a-online I'll jump in here. For a single-seat aircraft, you don't need an audio panel or an isolation amplifier. All you need to do is connect your audio sources to the headphone audio bus and wire the headset mic to the SL-30 directly. To connect to the audio bus, the SL-30 *must* have a series resistor (anything from 300 to 600 ohms should work). Connect the SL-30 audio to one end of the resistor, and the connect the other end of the resistor to the common audio bus. To this bus, connect any other audio sources such as your marker beacon receiver, audio alarms and of course, your headphones. For an external audio source, such as an MP3 player, you will need to wire series resistors in the left and right audio channels as well, connecting them both to the common audio bus. This will give you mono music in the headset. Stereo audio is more involved, but follows the same principal. Follow the resistor procedure for any low-impedance audio source. It won't hurt to have them in place for all audio bus connections (except your headphones), but it's easier to wire without them. I hope this is clear. If not, I can send a diagram. Vern Little Dee L. Conger wrote: >--> AeroElectric-List message posted by: "Dee L. Conger" > >Hi Bob, > > >I'm currently working on an electrical system for my Yak 50, which is a >single seat Russian airplane. The plane will be equipped with an SL30 >Nav/Com, an SL70 Transponder and a Blue Mountain EFIS sport - powered by >a B&C pad-mounted alternator (for M14P). I'm not quite sure what to do >about an audio panel - since I have only one Nav/Com, there doesn't seem >to be a real need for one, expect for mixing in music and maybe for the >marker beacon receiver. I plan on using a stereo headset and would like >to be able to pipe in MP3s. > > >Would your isolation amp be a good solution? Or, can you recommend a >small, single place audio panel? > > >Thanks, > > >Dee L. Conger >(858) 754-3010 Direct > >This email and any attachments thereto may contain private, >confidential, and privileged material for the sole use of the intended >recipient. Any review, copying, or distribution of this email (or any >attachments thereto) by others is strictly prohibited. If you are not >the intended recipient, please contact the sender immediately and >permanently delete the original and any copies of this email and any >attachments thereto. > > > > -- No virus found in this outgoing message. Checked by AVG Anti-Virus. ________________________________ Message 11 ____________________________________ Time: 10:06:53 AM PST US Subject: AeroElectric-List: Apollo SL40 From: "John Tvedte" --> AeroElectric-List message posted by: "John Tvedte" Say - does anyone know what the wiring diagram for an SL40 is - concerning the 37 pin connector? The wiring diagrams I have only list pinouts for the 15 pin connector. Thanks, John ________________________________ Message 12 ____________________________________ Time: 10:32:28 AM PST US From: Walter Tondu Subject: Re: AeroElectric-List: Apollo SL40 --> AeroElectric-List message posted by: Walter Tondu On 03/17 12:06, John Tvedte wrote: > --> AeroElectric-List message posted by: "John Tvedte" > > Say - does anyone know what the wiring diagram for an SL40 is - concerning the 37 pin connector? The wiring diagrams I have only list pinouts for the 15 pin connector. I'm pretty sure the 37 pin connector is only used on the SL30 Nav/Com. It's unused on the SL40. Here's the link for the SL30. http://www.garmin.com/manuals/SL30Nav_Comm_InstallationManual.pdf -- Walter Tondu http://www.rv7-a.com ________________________________ Message 13 ____________________________________ Time: 10:41:31 AM PST US From: "James E. Clark" Subject: RE: AeroElectric-List: Audio panel for single seat Yak --> AeroElectric-List message posted by: "James E. Clark" Although Vern is correct, here is another perspective. Get a good stereo audio panel (maybe a Garmin 340 or PS Engineering unit) and save the hassle. It will cost you a few $$ but then everything is nicely packaged and will accommodate expansion. We have the SL30 radio and I did something similar to what Vern is recommending. Later we decided to add a marker beacon to the already added stereo music in to the intercom. An audio panel from the beginning would have been less work. James p.s. You might also get better "squelch" control for the Yak noise as well from an integrated unit. | -----Original Message----- | From: owner-aeroelectric-list-server@matronics.com [mailto:owner- | aeroelectric-list-server@matronics.com] On Behalf Of rv-9a-online | Sent: Thursday, March 17, 2005 12:58 PM | To: aeroelectric-list@matronics.com | Subject: Re: AeroElectric-List: Audio panel for single seat Yak | | --> AeroElectric-List message posted by: rv-9a-online | | I'll jump in here. | | For a single-seat aircraft, you don't need an audio panel or an | isolation amplifier. | | All you need to do is connect your audio sources to the headphone audio | bus and wire the headset mic to the SL-30 directly. | | To connect to the audio bus, the SL-30 *must* have a series resistor | (anything from 300 to 600 ohms should work). Connect the SL-30 audio to | one end of the resistor, and the connect the other end of the resistor | to the common audio bus. To this bus, connect any other audio sources | such as your marker beacon receiver, audio alarms and of course, your | headphones. | | For an external audio source, such as an MP3 player, you will need to | wire series resistors in the left and right audio channels as well, | connecting them both to the common audio bus. This will give you mono | music in the headset. Stereo audio is more involved, but follows the | same principal. | | Follow the resistor procedure for any low-impedance audio source. It | won't hurt to have them in place for all audio bus connections (except | your headphones), but it's easier to wire without them. | | I hope this is clear. If not, I can send a diagram. | | Vern Little | | {SNIP} ________________________________ Message 14 ____________________________________ Time: 10:43:34 AM PST US Subject: RE: AeroElectric-List: Audio panel for single seat Yak From: "Dee L. Conger" --> AeroElectric-List message posted by: "Dee L. Conger" Thanks - this is very helpful. What is the purpose of the resistors? Also, I would strongly prefer to retain stereo music - maybe this is where the isolation amp would be helpful? Dee L. Conger (858) 754-3010 Direct -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of rv-9a-online Subject: Re: AeroElectric-List: Audio panel for single seat Yak --> AeroElectric-List message posted by: rv-9a-online I'll jump in here. For a single-seat aircraft, you don't need an audio panel or an isolation amplifier. All you need to do is connect your audio sources to the headphone audio bus and wire the headset mic to the SL-30 directly. To connect to the audio bus, the SL-30 *must* have a series resistor (anything from 300 to 600 ohms should work). Connect the SL-30 audio to one end of the resistor, and the connect the other end of the resistor to the common audio bus. To this bus, connect any other audio sources such as your marker beacon receiver, audio alarms and of course, your headphones. For an external audio source, such as an MP3 player, you will need to wire series resistors in the left and right audio channels as well, connecting them both to the common audio bus. This will give you mono music in the headset. Stereo audio is more involved, but follows the same principal. Follow the resistor procedure for any low-impedance audio source. It won't hurt to have them in place for all audio bus connections (except your headphones), but it's easier to wire without them. I hope this is clear. If not, I can send a diagram. Vern Little Dee L. Conger wrote: >--> AeroElectric-List message posted by: "Dee L. Conger" > >Hi Bob, > > >I'm currently working on an electrical system for my Yak 50, which is a >single seat Russian airplane. The plane will be equipped with an SL30 >Nav/Com, an SL70 Transponder and a Blue Mountain EFIS sport - powered by >a B&C pad-mounted alternator (for M14P). I'm not quite sure what to do >about an audio panel - since I have only one Nav/Com, there doesn't seem >to be a real need for one, expect for mixing in music and maybe for the >marker beacon receiver. I plan on using a stereo headset and would like >to be able to pipe in MP3s. > > >Would your isolation amp be a good solution? Or, can you recommend a >small, single place audio panel? > > >Thanks, > > >Dee L. Conger >(858) 754-3010 Direct > >This email and any attachments thereto may contain private, >confidential, and privileged material for the sole use of the intended >recipient. Any review, copying, or distribution of this email (or any >attachments thereto) by others is strictly prohibited. If you are not >the intended recipient, please contact the sender immediately and >permanently delete the original and any copies of this email and any >attachments thereto. > > > > -- No virus found in this outgoing message. Checked by AVG Anti-Virus. ________________________________ Message 15 ____________________________________ Time: 10:47:53 AM PST US From: Richard Tasker Subject: Re: AeroElectric-List: Apollo SL40 --> AeroElectric-List message posted by: Richard Tasker The SL-40 doesn't have a 37 pin connector. Dick Tasker John Tvedte wrote: >--> AeroElectric-List message posted by: "John Tvedte" > >Say - does anyone know what the wiring diagram for an SL40 is - concerning the 37 pin connector? The wiring diagrams I have only list pinouts for the 15 pin connector. > >Thanks, > >John > > ________________________________ Message 16 ____________________________________ Time: 12:26:13 PM PST US From: Fiveonepw@aol.com Subject: Re: AeroElectric-List: OV protection debate --> AeroElectric-List message posted by: Fiveonepw@aol.com In a message dated 3/17/05 7:17:08 AM Central Standard Time, limadelta@gmail.com writes: > Many readers of this list won't benefit if the idea can't be > made simple enough for OBAMers to translate into their projects. >>> The benefits I've received here are incalculable, other than by the measure provided by a flying RV with a suberbly functioning electrical system, due in large part to what I've learned by reading things here that were waaaaayyy over my head in the old daze, now made mostly clear after discussion, thought and implementation. Mind you there ARE some topics far beyond my grokkage, but those are easily deleted (ere I offer to join the discussion, much to everybody else's benefit, I am certain...) On the occasions I am charged with an apprentice (the REAL ones- not from idiot tube) I often warn them I will send them into technical overload and to get used to it- next time they hear the topic, they at least will have an anchorage point, however tenuous, to the discussion. I don't expect them to learn anything at first pass, but after seeing an apple for the first time and holding one in your hands a few times, sooner or later you learn you can eat it... Mark Phillips - do not archive ________________________________ Message 17 ____________________________________ Time: 12:29:02 PM PST US From: "John Danielson" Subject: RE: AeroElectric-List: Apollo SL40 --> AeroElectric-List message posted by: "John Danielson" The SL-40 has a 15 pin connector. Go to http://www.rv7-a.com/manuals/SL40Comm_InstallationManual.pdf for an installation manual. John L. Danielson -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Richard Tasker Subject: Re: AeroElectric-List: Apollo SL40 --> AeroElectric-List message posted by: Richard Tasker The SL-40 doesn't have a 37 pin connector. Dick Tasker John Tvedte wrote: >--> AeroElectric-List message posted by: "John Tvedte" > >Say - does anyone know what the wiring diagram for an SL40 is - concerning the 37 pin connector? The wiring diagrams I have only list pinouts for the 15 pin connector. > >Thanks, > >John > > ________________________________ Message 18 ____________________________________ Time: 03:19:43 PM PST US From: rv-9a-online Subject: Re: AeroElectric-List: Audio panel for single seat Yak --> AeroElectric-List message posted by: rv-9a-online To get stereo music, do the following: Make two audio buses: L & R All of your monophonic sources are connected to both of the L & R buses with series resistors (on connected to L and the other to R). . All of your stereophonic sources are connected left channel to L and right channel to R with individual series resistors. As for using an isolation amp... you have a simple panel and a very simple audio system. An isolation amp like Bob supplies on his website could be used, but isn't really necessary. A full audio panel is overkill, in my opinion. Vern Dee L. Conger wrote: >--> AeroElectric-List message posted by: "Dee L. Conger" > >Thanks - this is very helpful. What is the purpose of the resistors? >Also, I would strongly prefer to retain stereo music - maybe this is >where the isolation amp would be helpful? > >Dee L. Conger >(858) 754-3010 Direct >-----Original Message----- >From: owner-aeroelectric-list-server@matronics.com >[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of >rv-9a-online >To: aeroelectric-list@matronics.com >Subject: Re: AeroElectric-List: Audio panel for single seat Yak > >--> AeroElectric-List message posted by: rv-9a-online > > >I'll jump in here. > >For a single-seat aircraft, you don't need an audio panel or an >isolation amplifier. > >All you need to do is connect your audio sources to the headphone audio >bus and wire the headset mic to the SL-30 directly. > >To connect to the audio bus, the SL-30 *must* have a series resistor >(anything from 300 to 600 ohms should work). Connect the SL-30 audio to > >one end of the resistor, and the connect the other end of the resistor >to the common audio bus. To this bus, connect any other audio sources >such as your marker beacon receiver, audio alarms and of course, your >headphones. > >For an external audio source, such as an MP3 player, you will need to >wire series resistors in the left and right audio channels as well, >connecting them both to the common audio bus. This will give you mono >music in the headset. Stereo audio is more involved, but follows the >same principal. > >Follow the resistor procedure for any low-impedance audio source. It >won't hurt to have them in place for all audio bus connections (except >your headphones), but it's easier to wire without them. > >I hope this is clear. If not, I can send a diagram. > >Vern Little > > >Dee L. Conger wrote: > > > >>--> AeroElectric-List message posted by: "Dee L. Conger" >> >> > > > >>Hi Bob, >> >> >>I'm currently working on an electrical system for my Yak 50, which is a >>single seat Russian airplane. The plane will be equipped with an SL30 >>Nav/Com, an SL70 Transponder and a Blue Mountain EFIS sport - powered >> >> >by > > >>a B&C pad-mounted alternator (for M14P). I'm not quite sure what to do >>about an audio panel - since I have only one Nav/Com, there doesn't >> >> >seem > > >>to be a real need for one, expect for mixing in music and maybe for the >>marker beacon receiver. I plan on using a stereo headset and would >> >> >like > > >>to be able to pipe in MP3s. >> >> >>Would your isolation amp be a good solution? Or, can you recommend a >>small, single place audio panel? >> >> >>Thanks, >> >> >>Dee L. Conger >>(858) 754-3010 Direct >> >>This email and any attachments thereto may contain private, >>confidential, and privileged material for the sole use of the intended >>recipient. Any review, copying, or distribution of this email (or any >>attachments thereto) by others is strictly prohibited. If you are not >>the intended recipient, please contact the sender immediately and >>permanently delete the original and any copies of this email and any >>attachments thereto. >> >> >> >> >> >> > > > > -- No virus found in this outgoing message. Checked by AVG Anti-Virus. ________________________________ Message 19 ____________________________________ Time: 03:49:29 PM PST US From: Andrew Rowley Subject: Re: AeroElectric-List: Re: White Paper on Crowbar OV Protection --> AeroElectric-List message posted by: Andrew Rowley Vern W. wrote: > One thing though: I AM interested in a follow up to where it was found > (anecdotally for the moment) that alternators sold by Van's seem to fail > when installed with the crowbar OV protection circuit and don't otherwise. > If true, then something is obviously going on that needs to be looked at a > bit closer. Any ideas on that? I don't know anything about the failures that have been reported, but the issue does raise some questions before I would point to the OV protection: What were the symptoms of the failure? Would the failure have been detected without OV protection? If the failure is being blamed on the OVP, presumably the OVP has tripped at some point. What caused the trip? Doesn't that indicate a problem before the OVP tripped? If you had a problem with the OVP repeatedly tripping, you would be likely to investigate the problem, and an alternator/regulator problem is a likely culprit. Would the fault be detected at all in an aircraft without OV protection? I could imagine that if the only problem was a slightly high voltage, it could go for a long time without being detected, or considered serious enough to fix. If, on the other hand, the problem was that the alternator failed to charge after an OVP trip, and there isn't a no-charge problem on aircraft without the OVP, the evidence does point to a problem related to the OVP. I just read back through a few of the previous messages... Paul Messinger said "100% of the failed alternators were the result of the OVP whether it was a crow bar device or a device that simply opened the "B" lead." If a device that simply opens the B lead is enough to damage the alternator, it doesn't sound like the real reason is the OVP module (although it is possible it could make a problem more likely). It suggests to me that these alternators should not be disconnected at all once running, and if you want the ability to do that maybe they are not suitable. Of the thousands of aircraft flying without failures, how many have tested what happens if the alternator is disconnected? ________________________________ Message 20 ____________________________________ Time: 04:26:41 PM PST US From: Andrew Rowley Subject: Re: AeroElectric-List: White Paper on Crowbar OV Protection --> AeroElectric-List message posted by: Andrew Rowley Robert L. Nuckolls, III wrote: > See: > > http://www.aeroelectric.com/articles/Crobar_OV_Protection/Crowbar_White_Paper.pdf I have a couple of queries... If I am understanding it correctly, you make the comment that the alternator output is reduced when the SCR fires, because the field voltage is reduced to the voltage across the SCR, about 2 volts. However, doesn't the internally regulated alternator supply the field voltage internally, which is why reducing the (external) field voltage to 0 doesn't shut off the alternator? I wouldn't be surprised if there was a diode in the field supply to ensure that the alternator could not supply current through the field terminal, in which case shorting this circuit shouldn't have an effect on the internal field supply at all. I would imagine that the internal field supply paths would be shorter and lower resistance than the paths through the bus, so the field voltage is likely to be at least as high as the bus voltage, possibly higher. Do we know how much field voltage internally regulated alternators actually require to produce full output? I imagine this could be lower than 12V. ________________________________ Message 21 ____________________________________ Time: 04:42:27 PM PST US From: "Pat Hatch" Subject: RE: AeroElectric-List: Using a 115 volt 400 hz device in a 12 volt airplane --> AeroElectric-List message posted by: "Pat Hatch" Bob, Just out of curiosity, how and why did the 400 Hz convention come about for airplanes? Since power is not dependent on frequency (I think), I'm curious about the other advantages of going to the higher frequencies. I seem to recall the formula for power is P=VI. Pat Hatch Do not archive -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III volt airplane Subject: Re: AeroElectric-List: Using a 115 volt 400 hz device in a 12 volt airplane --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" volt airplane AC power systems are the wave of the future for most airplanes above 15,000 pounds. Our Horizon uses a wild frequency AC system and I'm specifying some AC generation equipment onto a much smaller airplane. Our smaller Hawkers have big inverters. Now, if one wants to talk about WIRE WEIGHT reduction, high voltage AC is the way to get it. 208V 3-phase provides 115V from any leg to ground for small appliances. But when run through a rectifier, the 208 3-phase produces 270 VDC to run brushless DC motors. An air conditioner system that draws 200A at 28v draws only 20A at 270 VDC. This current is easily carried on a twisted trio of 16 AWG wires where it took a pair of 2AWG wires before. Further, the ship's airframe is NOT used for grounding on the high power 3-phase systems so that no ground loop noises are injected to other systems. Inverters for developing 400Hz AC come in ALL sizes ranging from 25 watt devices weighing perhaps 8 ounces and used to drive an instrument up to 1500 watt hogs that weigh in around 40 pounds and have BIG cooling fans on them. The very best way to generate lots of AC is from an engine driven alternator. 400 Hz AC power has been around since before WWII on larger aircraft for a variety of task but until 1950's was not used for whole-aircraft power. I think our Horizon has two transformer/rectifiers that develop about 50A each to handle ALL DC requirements. Everything else runs from the AC power. The Beechjet has two 400A generators to run it's DC only systems. Bob . . . ________________________________ Message 22 ____________________________________ Time: 05:03:40 PM PST US Subject: Re: AeroElectric-List: White Paper on Crowbar OV Protection From: "Matt Prather" --> AeroElectric-List message posted by: "Matt Prather" Hi... Are you new to the list? Your questions have been discussed at length in the recent past. You have access to the easily searchable archive by clicking on one of the links in the bottom of the message. http://www.matronics.com/archives By the way, who are you? Regards, Matt- VE N34RD, C150 N714BK > --> AeroElectric-List message posted by: Andrew Rowley > > > Robert L. Nuckolls, III wrote: > >> See: >> >> http://www.aeroelectric.com/articles/Crobar_OV_Protection/Crowbar_White_Paper.pdf > > I have a couple of queries... > > If I am understanding it correctly, you make the comment that the > alternator output is reduced when the SCR fires, because the field > voltage is reduced to the voltage across the SCR, about 2 volts. > > However, doesn't the internally regulated alternator supply the field > voltage internally, which is why reducing the (external) field voltage > to 0 doesn't shut off the alternator? I wouldn't be surprised if there > was a diode in the field supply to ensure that the alternator could not > supply current through the field terminal, in which case shorting this > circuit shouldn't have an effect on the internal field supply at all. > > I would imagine that the internal field supply paths would be shorter > and lower resistance than the paths through the bus, so the field > voltage is likely to be at least as high as the bus voltage, possibly > higher. Do we know how much field voltage internally regulated > alternators actually require to produce full output? I imagine this > could be lower than 12V. > > ________________________________ Message 23 ____________________________________ Time: 05:20:25 PM PST US From: james freeman Subject: Re: AeroElectric-List: Audio panel for single seat Yak --> AeroElectric-List message posted by: james freeman Here's yet another perspective ;-D I doubt you'll find a need in the future for a marker beacon receiver in a Yak 50. In fact, I would call the SL30 overkill. do you really need VOR/glideslope?. All of the SL series comms are great radios, with essentially the functionality of two comms and an audio panel built in. Since you don't need an intercom, why not get one of the "Muse" gizmos (I think Lightspeed sells these) to put stereo directly into the headset. In fact, I have seen newer stereo headsets with their own input jacks in the earcups. This would be cheaper and easier, and give you better sound (stereo). FWIW James Freeman On Mar 17, 2005, at 12:38 PM, James E. Clark wrote: > --> AeroElectric-List message posted by: "James E. Clark" > > > Although Vern is correct, here is another perspective. > > Get a good stereo audio panel (maybe a Garmin 340 or PS Engineering > unit) > and save the hassle. It will cost you a few $$ but then everything is > nicely > packaged and will accommodate expansion. > > We have the SL30 radio and I did something similar to what Vern is > recommending. Later we decided to add a marker beacon to the already > added > stereo music in to the intercom. An audio panel from the beginning > would > have been less work. ________________________________ Message 24 ____________________________________ Time: 05:42:47 PM PST US From: Andrew Rowley Subject: Re: AeroElectric-List: White Paper on Crowbar OV Protection --> AeroElectric-List message posted by: Andrew Rowley Matt Prather wrote: > Hi... > > Are you new to the list? > > Your questions have been discussed at length in the recent past. > > You have access to the easily searchable archive by clicking on one of the > links in the bottom of the message. > > http://www.matronics.com/archives > > By the way, who are you? Hi, I have been lurking on the list for a while, reading and learning but not posting. I'm sorry if I was supposed to introduce myself before posting. I understand that the issues have been discussed at length, but have they been resolved? As I understand it Paul says that when the B-lead is disconnected the alternator is producing full output due to the low bus voltage, but Bob is saying it is not capable at that point because the field voltage is very low. I'm just trying to ask a question to help me understand which is correct. Who am I? A builder in Australia, building a Rans S6S. It will have a Rotax, so the issue with the Vans alternators is academic for me, but Bob's suggested OVP is similar even if the regulator is not. ________________________________ Message 25 ____________________________________ Time: 05:59:13 PM PST US From: Ken Subject: Re: AeroElectric-List: White Paper on Crowbar OV Protection --> AeroElectric-List message posted by: Ken Andrew Rowley wrote: >--> AeroElectric-List message posted by: Andrew Rowley > >Robert L. Nuckolls, III wrote: > >>See: >> >>http://www.aeroelectric.com/articles/Crobar_OV_Protection/Crowbar_White_Paper.pdf >> >> > >I have a couple of queries... > >If I am understanding it correctly, you make the comment that the >alternator output is reduced when the SCR fires, because the field >voltage is reduced to the voltage across the SCR, about 2 volts. > >However, doesn't the internally regulated alternator supply the field >voltage internally, which is why reducing the (external) field voltage >to 0 doesn't shut off the alternator? I wouldn't be surprised if there >was a diode in the field supply to ensure that the alternator could not >supply current through the field terminal, in which case shorting this >circuit shouldn't have an effect on the internal field supply at all. > > Some do, some don't. Some fellows are using alternators that date back to at least the mid 70's. Some will start without a turn on signal. Some won't. The spec for the control chip that I mentioned this morning said that 2 volts would turn it on but IIRC it wasn't guaranteed to turn off until the control terminal was pulled below a half volt. It is reasonable to guess that the crowbar may turn off some internally regulated alternator fields but I wouldn't count on it. >I would imagine that the internal field supply paths would be shorter >and lower resistance than the paths through the bus, so the field >voltage is likely to be at least as high as the bus voltage, possibly >higher. Do we know how much field voltage internally regulated >alternators actually require to produce full output? I imagine this >could be lower than 12V. > > > These regulators rapidly switch the field on and off. So the voltage is cycling nominally between 0 and 12 volts. At low rpm it may be a constant 12 volts and perhaps flow 5 amps to command high output current. At high rpm, I believe the field may only need to be on for a short period between each off pulse to command high output. The average current may be only an amp or so. This is known as a small duty cycle. So you are correct that it is possible to get high output at fairly low field voltage if the control circuit has failed on continuously. With so many different designs I think the only sure way to shut these things off is to disconnect the alternator (disconnect the B lead) unless someone does a lot of testing with a specific alternator. Ken ________________________________ Message 26 ____________________________________ Time: 06:04:29 PM PST US From: Ken Subject: Re: AeroElectric-List: Using a 115 volt 400 hz device in a 12 volt airplane --> AeroElectric-List message posted by: Ken 400 hertz magnetic devices such as transformers are much smaller and lighter than 60 Hz devices for the same power. Ken Pat Hatch wrote: >--> AeroElectric-List message posted by: "Pat Hatch" > >Bob, > >Just out of curiosity, how and why did the 400 Hz convention come about for >airplanes? Since power is not dependent on frequency (I think), I'm curious >about the other advantages of going to the higher frequencies. I seem to >recall the formula for power is P=VI. > >Pat Hatch > > ________________________________ Message 27 ____________________________________ Time: 06:08:45 PM PST US Subject: RE: AeroElectric-List: White Paper on Crowbar OV Protection From: "Chuck Jensen" --> AeroElectric-List message posted by: "Chuck Jensen" Andrew, Welcome aboard. Don't be a 'lurker'. We already have plenty of them in our country already. Just jump in..the water's fine. by the way, do you happen to be in the Sidney area? If you are, if you spot a fellow building a Dupont 'better living through plastics' plane with the engine on the wrong end, say hi. That'd be Greg Poole, building a Velocity. Chuck Do Not Archive -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Andrew Rowley Subject: Re: AeroElectric-List: White Paper on Crowbar OV Protection --> AeroElectric-List message posted by: Andrew Rowley Matt Prather wrote: > Hi... > > Are you new to the list? > > Your questions have been discussed at length in the recent past. > > You have access to the easily searchable archive by clicking on one of the > links in the bottom of the message. > > http://www.matronics.com/archives > > By the way, who are you? Hi, I have been lurking on the list for a while, reading and learning but not posting. I'm sorry if I was supposed to introduce myself before posting. I understand that the issues have been discussed at length, but have they been resolved? As I understand it Paul says that when the B-lead is disconnected the alternator is producing full output due to the low bus voltage, but Bob is saying it is not capable at that point because the field voltage is very low. I'm just trying to ask a question to help me understand which is correct. Who am I? A builder in Australia, building a Rans S6S. It will have a Rotax, so the issue with the Vans alternators is academic for me, but Bob's suggested OVP is similar even if the regulator is not. ________________________________ Message 28 ____________________________________ Time: 06:17:24 PM PST US Subject: Re: AeroElectric-List: White Paper on Crowbar OV Protection From: "Matt Prather" --> AeroElectric-List message posted by: "Matt Prather" Hello (I am guessing) Andrew, I apologize if I sounded frosty. No introductions necessary. I just like to poke fun at people when they don't sign their emails in any way. Maybe a silly hangup on my part. I do believe your questions have been answered in the archive. Maybe someone else will re-answer them. Regards, Matt- VE N34RD > --> AeroElectric-List message posted by: Andrew Rowley > > > Matt Prather wrote: > >> Hi... >> >> Are you new to the list? >> >> Your questions have been discussed at length in the recent past. >> >> You have access to the easily searchable archive by clicking on one of >> the links in the bottom of the message. >> >> http://www.matronics.com/archives >> >> By the way, who are you? > > Hi, > > I have been lurking on the list for a while, reading and learning but > not posting. I'm sorry if I was supposed to introduce myself before > posting. > > I understand that the issues have been discussed at length, but have > they been resolved? As I understand it Paul says that when the B-lead is > disconnected the alternator is producing full output due to the low bus > voltage, but Bob is saying it is not capable at that point because the > field voltage is very low. I'm just trying to ask a question to help me > understand which is correct. > > Who am I? A builder in Australia, building a Rans S6S. It will have a > Rotax, so the issue with the Vans alternators is academic for me, but > Bob's suggested OVP is similar even if the regulator is not. > > ________________________________ Message 29 ____________________________________ Time: 06:18:16 PM PST US From: James Freeman Subject: Re: AeroElectric-List: Audio panel for single seat Yak --> AeroElectric-List message posted by: James Freeman On Mar 17, 2005, at 7:19 PM, james freeman wrote: > --> AeroElectric-List message posted by: james freeman > > > Here's yet another perspective ;-D And here is a link which might be helpful: http://www.avionicswest.com/muse.html#Muse ________________________________ Message 30 ____________________________________ Time: 06:29:02 PM PST US Subject: RE: AeroElectric-List: Audio panel for single seat Yak From: "Dee L. Conger" --> AeroElectric-List message posted by: "Dee L. Conger" Thanks for the ideas - I agree about the need for marker beacon. However, my Yak 50 will be IFR capable, which will come in handy in San Diego where we often have overcast mornings. My new panel has a Blue Mountain EFIS Sport hooked up to the SL30 - should work quite well. I'm also installing the EDM-930, which JPI promises will be 9 cylinder capable shortly. I estimate that the weight savings alone of this new panel w/ B&C alternator will approach 100 Lbs in the Yak - the Russian stuff is VERY heavy. ________________________________ From: owner-aeroelectric-list-server@matronics.com on behalf of james freeman Subject: Re: AeroElectric-List: Audio panel for single seat Yak --> AeroElectric-List message posted by: james freeman Here's yet another perspective ;-D I doubt you'll find a need in the future for a marker beacon receiver in a Yak 50. In fact, I would call the SL30 overkill. do you really need VOR/glideslope?. All of the SL series comms are great radios, with essentially the functionality of two comms and an audio panel built in. Since you don't need an intercom, why not get one of the "Muse" gizmos (I think Lightspeed sells these) to put stereo directly into the headset. In fact, I have seen newer stereo headsets with their own input jacks in the earcups. This would be cheaper and easier, and give you better sound (stereo). FWIW James Freeman On Mar 17, 2005, at 12:38 PM, James E. Clark wrote: > --> AeroElectric-List message posted by: "James E. Clark" > > > Although Vern is correct, here is another perspective. > > Get a good stereo audio panel (maybe a Garmin 340 or PS Engineering > unit) > and save the hassle. It will cost you a few $$ but then everything is > nicely > packaged and will accommodate expansion. > > We have the SL30 radio and I did something similar to what Vern is > recommending. Later we decided to add a marker beacon to the already > added > stereo music in to the intercom. An audio panel from the beginning > would > have been less work. ________________________________ Message 31 ____________________________________ Time: 06:56:10 PM PST US From: "Robert L. Nuckolls, III" volt airplane Subject: RE: AeroElectric-List: Using a 115 volt 400 hz device in a 12 volt airplane --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" volt airplane At 07:41 PM 3/17/2005 -0500, you wrote: >--> AeroElectric-List message posted by: "Pat Hatch" > >Bob, > >Just out of curiosity, how and why did the 400 Hz convention come about for >airplanes? Since power is not dependent on frequency (I think), I'm curious >about the other advantages of going to the higher frequencies. I seem to >recall the formula for power is P=VI. Power isn't but MAGNETICS are. A 100VA transformer for 60Hz weights almost exactly 6 times as much as one for 400Hz. This is why you can get so much from the modern small alternators. They put more poles on stators and rotors and spin them faster. Internal operating frequency goes up and watts/pound come down. Since the advent of more efficient magnetic materials, some wild frequency AC systems in aircraft as high as 800 Hz. A power transformer in your computer's power supply may be something on the order of 1.5" in diameter and about that high. It will weigh perhaps 4 ounces yet handles the AC power conditioning job for 300 watts of output. It operates in the 20,0000 - 60,000 Hz range. Bob . . . ________________________________ Message 32 ____________________________________ Time: 07:53:24 PM PST US From: Tim Olson Subject: Re: AeroElectric-List: OV protection debate --> AeroElectric-List message posted by: Tim Olson Would it maybe not help solve some of this debate as to the OV protection if perhaps Eric, Paul, and Bob all drew up their favorite OV protection circuit, and maybe one or all of them took the time to actually run them and produce a situation that would cause trouble? I know Bob ran his circuit to prove his....but I'd be interested to see a couple of different OV options, and graphs of voltage and current spikes that happened when an OV condition was created. It seems like all of this debating back and forth could be settled with just a few hours of directly compared experiments... Tim DO NOT ARCHIVE Mickey Coggins wrote: > --> AeroElectric-List message posted by: Mickey Coggins > > One of my favorite quotes. I used it a lot when I was > slinging code in a previous life. Another one, when > asked if it could get done faster if I had some help, > was "Adding a second woman to the job won't make the > baby come in 4.5 months." > > Please keep the debate going - I'm enjoying it, and learning > things along the way. > > Mickey > > > >>Einstein suggested things should be made as simple as possible...but >>no simpler. ... > > > ________________________________ Message 33 ____________________________________ Time: 08:49:05 PM PST US From: "James E. Clark" Subject: RE: AeroElectric-List: Audio panel for single seat Yak --> AeroElectric-List message posted by: "James E. Clark" This too is true. Before the SL30 + Marker Beacon, we had an SL40. I have flown planes with the SL40 and once you get it setup right, it is a great radio. I assumed, based on his question that he had already decided on the SL30 + Mkr Bcn and maybe even had them already in anticipation of IFR work. Given that he is single seat, it also simplifies it to the point of your recommendation ("Muse gizmo") being quite workable. Another James p.s. I bet he did not expect such a wide diversity of opinion on such a simple matter. :-) | -----Original Message----- | From: owner-aeroelectric-list-server@matronics.com [mailto:owner- | aeroelectric-list-server@matronics.com] On Behalf Of james freeman | Sent: Thursday, March 17, 2005 8:20 PM | To: aeroelectric-list@matronics.com | Subject: Re: AeroElectric-List: Audio panel for single seat Yak | | --> AeroElectric-List message posted by: james freeman | | Here's yet another perspective ;-D | | I doubt you'll find a need in the future for a marker beacon receiver | in a Yak 50. In fact, I would call the SL30 overkill. do you really | need VOR/glideslope?. All of the SL series comms are great radios, | with essentially the functionality of two comms and an audio panel | built in. Since you don't need an intercom, why not get one of the | "Muse" gizmos (I think Lightspeed sells these) to put stereo directly | into the headset. In fact, I have seen newer stereo headsets with | their own input jacks in the earcups. This would be cheaper and | easier, and give you better sound (stereo). | | FWIW | | James Freeman | |