---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Thu 04/17/03: 13 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:44 AM - Re: Nav/Strobe lights (Roberto Giusti) 2. 06:17 AM - Re: Nav/Strobe lights (Shaun Simpkins) 3. 06:56 AM - Problem with Whelen Stobe - Help (Timothy Freeze) 4. 07:53 AM - Re: Nav/Strobe lights (John & Amy Eckel) 5. 08:38 AM - Re: Problem with Whelen Stobe - Help (Shannon Knoepflein) 6. 08:54 AM - Re: Problem with Whelen Stobe - Help (Michel Therrien) 7. 01:01 PM - Power budget (Treff, Arthur) 8. 02:22 PM - Re: Power budget (Matt Prather) 9. 02:54 PM - Re: Power budget (Phil Birkelbach) 10. 03:31 PM - Nav/Strobe lights (BAKEROCB@aol.com) 11. 05:28 PM - Re: Problem with Whelen Stobe - Help (Jerzy Krasinski) 12. 08:33 PM - Re: Power budget (Richard Sipp) 13. 09:38 PM - Fw: PM-OV and E-bus switch (David Carter) ________________________________ Message 1 _____________________________________ Time: 04:44:21 AM PST US From: "Roberto Giusti" Subject: RE: AeroElectric-List: Nav/Strobe lights --> AeroElectric-List message posted by: "Roberto Giusti" I contacted Nova and they said that I would get the absolute brightest flash with their HPS4 power supply. The spec sheet states 28.5 Joules primary flash and 12.5 joules secondary flash in double flash mode. In fact it is so powerful that it won't work with their standard heads. They have special HPS heads (expensive and bulky), but on the phone they said that whelen heads should cope with this supply. So an option could be to use the Nova HPS4 power supply with Whelen heads. Roberto Giusti RV8 QB Italy roby@mail.com ________________________________ Message 2 _____________________________________ Time: 06:17:59 AM PST US From: "Shaun Simpkins" Subject: Re: AeroElectric-List: Nav/Strobe lights --> AeroElectric-List message posted by: "Shaun Simpkins" I obsessed about this subject a while ago. This is one of those subjects that a homebuilder's FAQ should address. Aeroflash strobes are, by their own admission, not compliant with today's strobe output requirements. Bob is right, it takes nearly 20 joules AND a concentrating lens like the ones that Whelen makes to meet the current FAA regs. If you're wanting to see a copy of the FAA regs, you can look up the page in your Aircraft Spruce catalog, or browse the Whelen website. If you want more detail, the FAA's website has tons of articles on lighting regs, definitions, and measurement methods. So why can Aeroflash continue to sell their product? In the certified market, to replace preexisting Aeroflash units. There are scads of Aeroflash strobes in all those pre-1980 Cessnas out there, and most every manufacturer at one time or another used Aeroflash. In the experimental market, it's often the case that those aircraft are not flown at night and the strobes are being bought for daytime visibility enhancement. There's no regs for daytime use of strobes. Inspectors often don't concentrate on strobe output when there are far more pressing safety issues to be judged. But if you want to be absolutely legal for night flight, Whelen equivalent strobes and power supplies are necessary. You'll notice that Cirrus and Lancair both use Whelen. Those with 28V systems in Europe can use Bosch as well... Shaun Simpkins ________________________________ Message 3 _____________________________________ Time: 06:56:09 AM PST US From: "Timothy Freeze" Subject: AeroElectric-List: Problem with Whelen Stobe - Help --> AeroElectric-List message posted by: "Timothy Freeze" Hi, I have the Whelen "a600" strobe and "hdacf" power supply on my cozy III. I bought the supply early in the project and when I finally completed it the supply had been sitting for 10 years! I now have over 200 hours on the aircraft but when I first turn on the strobe I can hear the charge and firing of the stobe. The noise goes away after about 10 minutes. I thought perhaps the battery was not fully charged or something like that so I put a trickle charger on the battery to see if that cured it. Nope. So I talked to the Whelen guy when I was at sun n fun and he said "The supply was too old and needed work" & "It's out warrenty and the capacitors were probably just old". He told me "It's cheaper to buy a new power supply". I thanked him for his help and went in search of a replacment supply. SHOCK AND AWE - well I priced it and it is $350 + shipping ... ouch. The whelen guy seemed kind of rude ... like he didn't really want to be at the show listening to customers. I felt he just wanted me to go away, so I didn't pester him. I just felt he wanted me to go away! He also didn't inspire my confidence that he knew what he was talking about. Just a feeling but I try to listen to them! I really want to get this fixed - I'm tired of people telling me it sounds like my ELT is going off when I key the mike after I first start off flying. So I trun the stobe off and ask if they still hear it - nope. Then I tell them I'm trying to fix it. I leave off the part about "I don't kanow how to fix it". :-) Since it is kind of a pain to remove the power supply (I have to take one wing off as I put the supply in the strake), and possibly expensive, do you think this is the problem or should I do more trouble shooting? Can I just buy new capacitor(s) from Newark or Digikey and save a pile of money? I know I can do the work as far as safely removing, discharging, and replacing capacitors unless they are some weird electrical or physical configuration and I can't get them commercially. I've montored this list for a long time now. This is my first request for help. I'd appreciate any shared thoughts, experience, or suggestions. Thanks in advance. Tim Cozy N215TW email at s35pilot@hotmail.com ________________________________ Message 4 _____________________________________ Time: 07:53:42 AM PST US From: John & Amy Eckel Subject: Re: AeroElectric-List: Nav/Strobe lights --> AeroElectric-List message posted by: John & Amy Eckel ----- Original Message ----- From: "Shaun Simpkins" Subject: Re: AeroElectric-List: Nav/Strobe lights > --> AeroElectric-List message posted by: "Shaun Simpkins" > > I obsessed about this subject a while ago. This is one of those subjects > that a homebuilder's FAQ should address. > > Aeroflash strobes are, by their own admission, not compliant with today's > strobe output requirements. Bob is right, it takes nearly 20 joules AND a > concentrating lens like the ones that Whelen makes to meet the current > FAA regs. > > If you're wanting to see a copy of the FAA regs, you can look up the page > in your Aircraft Spruce catalog, or browse the Whelen website. If you want > more detail, the FAA's website has tons of articles on lighting regs, definitions, > and measurement methods. > > So why can Aeroflash continue to sell their product? In the certified market, > to replace preexisting Aeroflash units. There are scads of Aeroflash strobes > in all those pre-1980 Cessnas out there, and most every manufacturer at one > time or another used Aeroflash. > In the experimental market, it's often the case that those aircraft are not flown > at night and the strobes are being bought for daytime visibility enhancement. > There's no regs for daytime use of strobes. Inspectors often don't concentrate > on strobe output when there are far more pressing safety issues to be judged. > > But if you want to be absolutely legal for night flight, Whelen equivalent strobes and > power supplies are necessary. You'll notice that Cirrus and Lancair > both use Whelen. Those with 28V systems in Europe can use Bosch as well... > > Shaun Simpkins Shaun, Thanks for clearing up this issue for me and doing the research. I have often wondered about the legality of the Aeroflash strobes. Thanks. John, A230 > > ________________________________ Message 5 _____________________________________ Time: 08:38:07 AM PST US From: "Shannon Knoepflein" Subject: RE: AeroElectric-List: Problem with Whelen Stobe - Help --> AeroElectric-List message posted by: "Shannon Knoepflein" Maybe try calling Whelen and explaining the situation. If they think its the power supply, tell them you'll buy a new power supply and change it out, but if that doesn't fix it, you will expect a full refund. Or, if you have a buddy that is building, just borrow his supply maybe and try that out? --- Shannon Knoepflein <---> kycshann@kyol.net -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Timothy Freeze Subject: AeroElectric-List: Problem with Whelen Stobe - Help --> AeroElectric-List message posted by: "Timothy Freeze" Hi, I have the Whelen "a600" strobe and "hdacf" power supply on my cozy III. I bought the supply early in the project and when I finally completed it the supply had been sitting for 10 years! I now have over 200 hours on the aircraft but when I first turn on the strobe I can hear the charge and firing of the stobe. The noise goes away after about 10 minutes. I thought perhaps the battery was not fully charged or something like that so I put a trickle charger on the battery to see if that cured it. Nope. So I talked to the Whelen guy when I was at sun n fun and he said "The supply was too old and needed work" & "It's out warrenty and the capacitors were probably just old". He told me "It's cheaper to buy a new power supply". I thanked him for his help and went in search of a replacment supply. SHOCK AND AWE - well I priced it and it is $350 + shipping ... ouch. The whelen guy seemed kind of rude ... like he didn't really want to be at the show listening to customers. I felt he just wanted me to go away, so I didn't pester him. I just felt he wanted me to go away! He also didn't inspire my confidence that he knew what he was talking about. Just a feeling but I try to listen to them! I really want to get this fixed - I'm tired of people telling me it sounds like my ELT is going off when I key the mike after I first start off flying. So I trun the stobe off and ask if they still hear it - nope. Then I tell them I'm trying to fix it. I leave off the part about "I don't kanow how to fix it". :-) Since it is kind of a pain to remove the power supply (I have to take one wing off as I put the supply in the strake), and possibly expensive, do you think this is the problem or should I do more trouble shooting? Can I just buy new capacitor(s) from Newark or Digikey and save a pile of money? I know I can do the work as far as safely removing, discharging, and replacing capacitors unless they are some weird electrical or physical configuration and I can't get them commercially. I've montored this list for a long time now. This is my first request for help. I'd appreciate any shared thoughts, experience, or suggestions. Thanks in advance. Tim Cozy N215TW email at s35pilot@hotmail.com ________________________________ Message 6 _____________________________________ Time: 08:54:49 AM PST US From: Michel Therrien Subject: Re: AeroElectric-List: Problem with Whelen Stobe - Help --> AeroElectric-List message posted by: Michel Therrien In my installation manual, it's written: "WARNING: Strobe light power supplies are meant to be used, not to remain in an inactive state. Any strobe light power supply that has been out of service for a long period of time is subject to failure because the electrolytic condenser loses its polarity formation. A strobe light power supply not having been used for one year or longer is vulnerable to failure." And the more interesting part: "If this is the case, it is recommended to start operating the system on a voltage that is reduced by 25% for 10 to 15 minutes before putting the power supply into normal service. This will preven t overheating of the condenser while they reform. If the power supply, after a long period of non use, is operated at full voltage immediately, there is an excellent possibiliyt that the condenser will become overheated." --- Timothy Freeze wrote: > --> AeroElectric-List message posted by: "Timothy > Freeze" > > Hi, > > I have the Whelen "a600" strobe and "hdacf" power > supply on my cozy III. I > bought the supply early in the project and when I > finally completed it the > supply had been sitting for 10 years! > http://search.yahoo.com ________________________________ Message 7 _____________________________________ Time: 01:01:39 PM PST US Subject: AeroElectric-List: Power budget From: "Treff, Arthur" --> AeroElectric-List message posted by: "Treff, Arthur" 'Letric Bob (and the list), I'm putting together my power budget for my RV-8's electrical system. When I use the max current draw shown on all the avionics specifications along with strobes, landing and taxi lights and pitot heat, I'm up towards 60 amps! Clearly I must be doing something wrong. Can you provide some guidance on how to size an alternator and if there is a multiplier that is normally used to calculate nominal current from the max that is published. It will be a basic IFR ship with pitot heat and lights and Trutrack with alt hold. For the GNS 430, for instance, Garmin tech support said that when the unit is just receiving in cruise, expect 1.5 amps; during approach phase, when driving needles and switching freq's and cursoring around, expect 3.0 amps. Then, when the mic is keyed, ADD another 6 amps. This appears very high to me, as the installation guide from Garmin specifies two inputs, each protected by a 5 amp fuse. With lighting, should I expect that the 100W landing light draws 8.3 amps at all times, or is this an inrush current? Whelen strobe power supply says its rated for 7 amps, is that the value I should put into my budget? I'm using a Piper heated pitot/static mast, but have no clue how much it draws. Most people I talk to say that a 40 amp alternator is more than most planes need. Any comments on how to get me there? Art Treff RV-8 ________________________________ Message 8 _____________________________________ Time: 02:22:39 PM PST US Subject: Re: AeroElectric-List: Power budget From: "Matt Prather" --> AeroElectric-List message posted by: "Matt Prather" Art, Please see my comments below. > --> AeroElectric-List message posted by: "Treff, Arthur" > > > 'Letric Bob (and the list), > > I'm putting together my power budget for my RV-8's electrical system. > When I use the max current draw shown on all the avionics specifications > along with strobes, landing and taxi lights and pitot heat, I'm up > towards 60 amps! Clearly I must be doing something wrong. Can you > provide some guidance on how to size an alternator and if there is a > multiplier that is normally used to calculate nominal current from the > max that is published. It will be a basic IFR ship with pitot heat and > lights and Trutrack with alt hold. > When doing a power budget, you are most interested in the average consumption. The max usage only really comes into play when deciding how big the wire and breaker need to be. > For the GNS 430, for instance, Garmin tech support said that when the > unit is just receiving in cruise, expect 1.5 amps; during approach > phase, when driving needles and switching freq's and cursoring around, > expect 3.0 amps. Then, when the mic is keyed, ADD another 6 amps. This > appears very high to me, as the installation guide from Garmin specifies > two inputs, each protected by a 5 amp fuse. 6 Amps seems high for continuous transmit, as that would be 72W burned, and at 50% efficiency ( a reasonable assumption for a transmitter) you would radiate 36W. I didn't think any GA radios are putting out that much. A 6A transient might be appropriate for figuring breaker size to avoid nuisance trips. For com radios, transponder, flap/trim/gear motors the standby current can be used for power budget. The duty cycle operated at max current rating is very low. > > With lighting, should I expect that the 100W landing light draws 8.3 > amps at all times, or is this an inrush current? Whelen strobe power > supply says its rated for 7 amps, is that the value I should put into my > budget? I'm using a Piper heated pitot/static mast, but have no clue > how much it draws. For lighting, you need to budget the bulb's rated demand. A 100W bulb uses at least 8.3A continuous, probably more if you consider that by the time you get to 12V, your LV light is flashing. If your alternator is keeping its end up, you are probably driving 13V to the bulb. Bob (and I believe others) has shown an analysis of strobe power use. Basically, you can take the energy (in Joules) of each flash and multiply that by the number of flashes per unit time to get the average wattage > > Most people I talk to say that a 40 amp alternator is more than most > planes need. Any comments on how to get me there? > If you do the analysis based on the duty cycle of each device I think it will all work out okay. Its not a problem if on a momentary basis your alternator doesn't keep up. I'll bet that in most cars if you are out driving during a summer evening rain storm with the AC/defr, wipers and headlights and then lower a window while sitting at a traffic light, you will dip into the reserves that the battery supplies. > Art Treff > RV-8 > > Regards, Matt- ________________________________ Message 9 _____________________________________ Time: 02:54:16 PM PST US From: "Phil Birkelbach" Subject: Re: AeroElectric-List: Power budget --> AeroElectric-List message posted by: "Phil Birkelbach" I am no expert but I have been doing my power budget lately as well. I used only continuous load numbers for devices that will be on together at any given time. I didn't count the flap motor, or the trim servos. I didn't include the power used during transmitting on the comm either. It is only going to be for a few seconds and the Alt will have a chance to catch up once I let go of the mic. Use the max numbers for sizing wire and the continuous numbers for alternator sizing. The idea is to only include loads that will be on together in the airplane. For instance. I will flash my landing lights during almost all operations this measn that only one will be on at a time so I only include one lamp in my continuous load power budget for enroute flight. When I enter the pattern to land at night both lights come on full time, but the autopilot is not part of this load because I turned it off. Yes the flap motor pulls 3A but why include it since it runs for about 30 seconds per flight. The battery is good for loads upwards of 200A. The GNS 430 numbers that you gave sound a little conservative but probably okay to use. The pitot heat will pull about 8Amps for every 100Watts of heat it makes. I looked at Gretz Aero and his are between 8 and 12 Amps. The 100Watt lamps will use up a little over 8 Amps continuously. P=VI. Power(Watts) = Voltage(Volts) x Current(Amps) (DC power only) So worst case is landing at night with the Pitot Heat on. Positon lights (6A) Two 100W Landing lights (16A) Strobes (7A) and Pitot Heat (10A) you are at 39Amps. I would imagine that you need a 60Amp alternator. Leave yourself some room for battery charging too. If you are right on the ragged edge there'll be no juice left to charge the battery. Godspeed, Phil Birkelbach - Houston Texas RV-7 N727WB (Reserved) - Fuselage http://www.myrv7.com ----- Original Message ----- From: "Treff, Arthur" Subject: AeroElectric-List: Power budget > --> AeroElectric-List message posted by: "Treff, Arthur" > > 'Letric Bob (and the list), > > I'm putting together my power budget for my RV-8's electrical system. When I use the max current draw shown on all the avionics specifications along with strobes, landing and taxi lights and pitot heat, I'm up towards 60 amps! Clearly I must be doing something wrong. Can you provide some guidance on how to size an alternator and if there is a multiplier that is normally used to calculate nominal current from the max that is published. It will be a basic IFR ship with pitot heat and lights and Trutrack with alt hold. > > For the GNS 430, for instance, Garmin tech support said that when the unit is just receiving in cruise, expect 1.5 amps; during approach phase, when driving needles and switching freq's and cursoring around, expect 3.0 amps. Then, when the mic is keyed, ADD another 6 amps. This appears very high to me, as the installation guide from Garmin specifies two inputs, each protected by a 5 amp fuse. > > With lighting, should I expect that the 100W landing light draws 8.3 amps at all times, or is this an inrush current? Whelen strobe power supply says its rated for 7 amps, is that the value I should put into my budget? I'm using a Piper heated pitot/static mast, but have no clue how much it draws. > > Most people I talk to say that a 40 amp alternator is more than most planes need. Any comments on how to get me there? > > Art Treff > RV-8 > > ________________________________ Message 10 ____________________________________ Time: 03:31:24 PM PST US From: BAKEROCB@aol.com Subject: AeroElectric-List: Nav/Strobe lights --> AeroElectric-List message posted by: BAKEROCB@aol.com IAeroElectric-List message previously posted by: Rico Voss << .....skip......My question is: Does the Airworthiness Cert. (Operating LImitations?) declare that the aircraft is equipped to fly at night, or does it say that it can be flown at night IF it meets the lighting requirements......skip.....--Richard >> 4/17/2003 Hello Richard, Here is an extract from my 4/13/2003 posting {...skip.... The Operating Limitations for your specific aircraft should have some words in it that read something like "After completion of Phase I flight testing, unless appropriately equipped for night and/or instument flight in accordance with 91.205, this aircraft is to be operated under VFR, day only." That means that once your aircraft is "appropriately equipped" and you have the transponder, encoder, and altimeter inspections required for IFR operations (and repeated every two years) you are good to go -- no "IFR certification" regarding the avionics equipment installed is involved**....skip.....} So the same philosophy applies to the lighting required for night operations -- the aircraft must be "appropriately equipped". In order to make that determination one must dig into the FAR's and determine what is "appropriate" in the eyes of the FAA. This subject has been written about before on the list and you can search the archives as well as the FAR's to arrive at your conclusion. 'OC' Baker, Builder of KIS TR-1 #116 4/14/97 - ?/?/? ________________________________ Message 11 ____________________________________ Time: 05:28:44 PM PST US From: Jerzy Krasinski Subject: Re: AeroElectric-List: Problem with Whelen Stobe - Help --> AeroElectric-List message posted by: Jerzy Krasinski Timothy Freeze wrote: > "....when I first turn on the strobe I can hear the charge and firing of the stobe. The noise goes away after about 10 minutes...." > It is not clear to me what are the symptoms. Strobe power supplies are always a little noisy. You can always hear high frequency ton of the high voltage converter, and you can always hear a quiet and periodic thumps when the strobe fires. Is that what you hear? If that is the case I do not see much wrong, the sound of the converter sometimes can get louder if a part of the laminated iron core gets loose. Or do you hear not periodic and quite loud sound reminding a small hammer strike against a metal, which typically happens without a flash. That is most likely a sound of the capacitor breaking down. The capacitor sometimes can get cured as described in another email by running the strobe for some time at reduced voltage. Or perhaps you hear it through the electrical installation in your headphones? And what happens after those 10 minutes? Is the strobe still working or it quits? Jerzy ________________________________ Message 12 ____________________________________ Time: 08:33:24 PM PST US From: "Richard Sipp" Subject: Re: AeroElectric-List: Power budget --> AeroElectric-List message posted by: "Richard Sipp" My RV-4 has the following electrical power consumers: landing lights (big old GE bulbs) nav lights GPS/com Nav/com transponder 3 unit strobes single cockpit flood led cockpit lighting dimmer VM1000 engine monitor intercom boost pump When all of this is operating (not transmitting) the amp load on the VM1000 is stable at 27 amps. I use a B&C 35 amp alternator. With the above load and 700 rpm the voltage drops from the normal 14.3 to 13.9. At any rpm above idle the voltage returns to 14.3. Normal day VFR cruise load is about 15 amps. Dick Sipp RV4 N250DS ________________________________ Message 13 ____________________________________ Time: 09:38:08 PM PST US From: "David Carter" Subject: Fw: AeroElectric-List: PM-OV and E-bus switch --> AeroElectric-List message posted by: "David Carter" Geof, I missed the response to your e-mail below. If you got one from Bob, and if you saved it, could you fwd it to me? Thanks. I've just studied the Z- diagrams in Aeroelectric Connection and re-read several chapters - I'm jumping in with both feet to become "an aircraft electrical systems designer (homebuilt)". I liked your 2nd question, about effect of having e-bus alternate feed switch on at same time battery switch was on. If it is true that there is "no effect", then there is a significant implication: The e-bus alternate feed switch could be left "on" all the time, in anticipation of a serious malfunction requiring killing the "battery switch and main bus". That would reduce the pilot actions from 2 to 1 - "turn off battery switch". You'd eliminate "then turn on essential bus alternate feed". (I was going to keep this "private" but because this system is being discussed on the list, I'll send it to the list, also.) David Carter ----- Original Message ----- From: "Geoff Evans" Subject: AeroElectric-List: PM-OV and E-bus switch > --> AeroElectric-List message posted by: Geoff Evans > > Bob. I sent this question to you via email, but perhaps it got lost by the > wayside. I'll repeat the question here. > > I have a question about the B&C PM-OV 14 product. > > It looks like all the same stuff you recommed for protecting the SD-8 > alternator, except the relay has extra lugs on it for the light bulb. The B&C > website says that, if wired according to their diagram, that the light will > illuminate if the alternator switch is left off or if the crowbar trips. > > I think I understand how the circuit trips, but I don't understand why you > would want a light that illuminates when the alternator is turned off... > Assuming that I'm going to use the SD-8 as a backup alternator, and following > your advice about not putting two alternators on the same bus at the same time, > why would I want a light that functioned in this manner? The light would be on > for all normal operations. > > Perhaps this product is designed to be used with the SD-8 when it is the only > alternator in the airplane, or when it is running on a separate, isolated > bus... > > ------ > > On a totally different subject.. What happens in your Z-11 circuit philosophy > if the E-bus alternate feed switch is on at the same time the battery master > switch is on? It looks to me like absolutely nothing, but I just wanted to make > sure. > > Thanks. > -Geoff > > RV-8 QB Fuselage >