---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Mon 03/14/05: 24 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:03 AM - Re: the ideal OV protection (maybe) (Jan de Jong) 2. 06:15 AM - Re: the ideal OV protection (maybe) (Jan de Jong) 3. 06:46 AM - Re: Re: the ideal OV protection (maybe) (Ken) 4. 08:39 AM - Re: [subaruaircraft] Re: CV Report on Ind Mod Failure (Brian Meyette) 5. 10:14 AM - Points for discussion OVP (Paul Messinger) 6. 01:12 PM - Re: Re: [subaruaircraft] Re: CV Report on Ind Mod Failure (Paul Messinger) 7. 01:15 PM - Re: Points for discussion OVP/correction (Paul Messinger) 8. 01:38 PM - Re: Points for discussion OVP//more (Paul Messinger) 9. 02:10 PM - Need known good mag (Charles Heathco) 10. 02:15 PM - Bob's approval electrical for Eggenfelner all electric system (B Tomm) 11. 02:15 PM - Re: Points for discussion OVP//more (Mickey Coggins) 12. 02:46 PM - Re: Points for discussion OVP//more (Paul Messinger) 13. 03:18 PM - Re: Points for discussion OVP/correction (Kingsley Hurst) 14. 04:45 PM - Re: Points for discussion OVP//more (Alex Peterson) 15. 05:40 PM - Re: Points for discussion OVP//more (John Schroeder) 16. 05:52 PM - Re: Points for discussion OVP//more (John Swartout) 17. 06:45 PM - LASAR/elecr ign (j1j2h3@juno.com) 18. 08:05 PM - Re: P-Mag Electrical System (Chris Byrne) 19. 08:18 PM - Re: Points for discussion OVP//more (John Swartout) 20. 08:33 PM - White Paper on Crowbar OV Protection (Robert L. Nuckolls, III) 21. 08:34 PM - Re: P-Mag Electrical System (Robert L. Nuckolls, III) 22. 08:43 PM - Re: Points for discussion OVP//more (Robert L. Nuckolls, III) 23. 08:52 PM - Electrical System Loads (was P-Mag) (Mitch Faatz) 24. 09:47 PM - Re: Electrical System Loads (was P-Mag) (Robert L. Nuckolls, III) ________________________________ Message 1 _____________________________________ Time: 05:03:16 AM PST US From: Jan de Jong Subject: AeroElectric-List: Re: the ideal OV protection (maybe) --> AeroElectric-List message posted by: Jan de Jong > > >In the Linear-OVM The chip is an LTC1696 which does decrease the trigger >delay with excessive rate of rise/time (dv/dt). Other strategies are >possible. > Interesting. Didn't know it existed. If I read the datasheet correctly the delay time shortens by a maximum factor of 2 when voltage increases by about 12% or more above trigger level Thank you for sharing what's inside the black box. Jan de Jong ________________________________ Message 2 _____________________________________ Time: 06:15:17 AM PST US From: Jan de Jong Subject: AeroElectric-List: Re: the ideal OV protection (maybe) --> AeroElectric-List message posted by: Jan de Jong Bob, Thank you for the voice of experience. I'm sure you're right that politeness is overrated nowadays. The OVM-14 is an amazing result with discrete parts. How a simple little unijunction thingy can make a whole lot of complexity unnecessary. Very interesting. I hope they will keep making them. Digikey seems to carry only PUT's now in the small unijunction categories. Jan de Jong ________________________________ Message 3 _____________________________________ Time: 06:46:20 AM PST US From: Ken Subject: Re: AeroElectric-List: Re: the ideal OV protection (maybe) --> AeroElectric-List message posted by: Ken Take a look at the newer crow bar circuit. It doesn't use the obsolete unijunction. Now it just uses a transistor trigger. Ken Jan de Jong wrote: >--> AeroElectric-List message posted by: Jan de Jong > >Bob, >Thank you for the voice of experience. >I'm sure you're right that politeness is overrated nowadays. >The OVM-14 is an amazing result with discrete parts. How a simple little >unijunction thingy can make a whole lot of complexity unnecessary. Very >interesting. I hope they will keep making them. Digikey seems to carry >only PUT's now in the small unijunction categories. >Jan de Jong > > > ________________________________ Message 4 _____________________________________ Time: 08:39:08 AM PST US From: "Brian Meyette" Subject: AeroElectric-List: RE: [subaruaircraft] Re: CV Report on Ind Mod Failure clamav-milter version 0.80j on andromeda --> AeroElectric-List message posted by: "Brian Meyette" As someone who does not plan to use the EXPBUS in my Eggenfellner installation, I would be most interested in something specific that Bob could put together. There was a lot of talk on the Eggenfellner list awhile back about someone designing a replacement for the EXPBUS, but it didnt materialize. I plan to use a combination of modified versions of Bobs existing layouts and a couple of the Hyperion components. Anything that Bob could put together as a complete, professional layout for the Eggenfellner FWF (all-electric, one alternator, dual batteries, with full backup, switchover, and protection) would be just great. brian expecting my STi in just a couple more weeks! http://brian76.mystarband.net/RV-7Ahome.htm -----Original Message----- From: B Tomm [mailto:fvalarm@rapidnet.net] Subject: RE: [subaruaircraft] Re: CV Report on Ind Mod Failure Gary, Thanks for the thoughtful reply. I'm sure Bob would be more than happy to adapt an electrical layout for the EGG package. That is essentially what Z-19 is. The only major mod that I can think of is putting the batteries aft of the baggage (RV7A H6). I have already talked to him about this but not finalized the details yet. I'll copy this email to Bob for comment. Bevan -----Original Message----- From: Gary Newsted [SMTP:fcs@jlc.net] Subject: [subaruaircraft] Re: CV Report on Ind Mod Failure I should point out that it is CV's optional enunciator module that I have trouble with. The EXP is fine for what it does. When I started working on the electrical design, I was given the EXP as a starting point. That is, take this design and make it work for us, improve it where you can, but most importantly, make it consistent. I feel that this has been achieved, and credit goes to many people in this newsgroup for contributing their expertise. The install guide presents an airworthy adaptation of the EXP for Eggenfellner engines, and tries to make the installation clear and simple. If you follow the guide, you will have a modern, airworthy system which is easy to operate and easy for us to diagnose should it ever give you trouble. I occasionally pick on people who deviate from this design, not because the design is perfect, but because I believe consistency is at the very root of the success of Eggenfellner packages. Let's face it, the thing that will bring down a Subaru will be fuel or electrical, so these two systems must be consistent, with lots of eyes reviewing these designs. One failure impacts all of us. Several times we have tossed around the pros and cons of "conventional" electrical designs, of which Aeroelectrics are a good example. I have not pursued this, although others have. In my eyes, conventional designs leave too many doors open which could result in inconsistency and even dangerous installations. If some qualified individual wanted to invest the time and energy into perfecting and thoroughly documenting a conventional design specifically for the Eggenfellner engines, I think Jan would support the effort (in spirit anyway). If you are a long ways away from wiring, don't rush into your decision either. There just might be better things coming soon. ADVERTISEMENT click here _____ * To visit your group on the web, go to: http://groups.yahoo.com/group/subaruaircraft/ * To unsubscribe from this group, send an email to: subaruaircraft-unsubscribe@yahoogroups.com Service . -- No virus found in this outgoing message. Checked by AVG Anti-Virus. ________________________________ Message 5 _____________________________________ Time: 10:14:02 AM PST US From: "Paul Messinger" Subject: AeroElectric-List: Points for discussion OVP --> AeroElectric-List message posted by: "Paul Messinger" Points for discussion OVP: Shorting/opening/limited current. Sorry I did not have the normal time to wordsmith this so its somewhat ruff J Some sort of buss over voltage protection (OVP) is needed in the unlikely event of the alternator regulator failing with a high voltage output. The output can go to over 100V under some conditions so this is a catastrophic event to an aircraft electrical system. One popular solution is an OVP device that shorts out the system bus and opens a circuit breaker that either removes power from an external alternator regulator or opens the "B" lead of an internally regulated alternator. (Ref: Aeroelectric connections build your own OVP). Let's look at voltage and current time line using this popular crowbar OVP and Contactor setup. Our testing included a duplicate of the suggested implementation with a 5 amp CB the OVP and a "B" lead power contactor with its coil was shunted with the common rectifier diode for "spike" suppression. Time is indicated in milliseconds. T-0 Bus voltage rises to above 16.2 V (the OVP trip point) and is not OV controlled. T-5 OVP Triggers after 5 ms of hi bus voltage. And the battery is shorted thru the OVP creating over 400 amps of current. (In one test it was over 730 amps) T-75 CB trips and the bus current returns to "normal" with the failed HV alternator back supplying its full output to the bus. T-125 "B" lead contactor opens and removes the alternator from the bus. So what has happened? First there is up to 5 ms of HI voltage applied to the bus before the crowbar causes a 400+ amp short on the bus. This causes the alternator to go to full current output. Depending on your setup the battery voltage could drop below the Voltage needed to run the electrically dependent engine and cause the engine to quit. Depends on the Engine computers ability to run during low voltages and not reset and restart which can take one or more seconds long enough to cause engine to stop and need to be restarted. Not nice J After 70 ms the CB pops and the short is removed from the bus and it goes into a high OV condition either from a shorted regulator or the full maximum load dump mode. In either case the bus voltage goes to several times normal depending on the alternator current capacity vs. the bus load. A load of 10 amps and a 40 amp load dump/fault creates a potential bus voltage 4 times normal or over 50V. This condition lasts for 50ms while the "B" lead contactor opens. Thus we see a 5 ms HV followed with a 70 ms 400 amp current pulse followed by a 50 ms HV on the bus. The time to open the CB is based on tests of 3 different brand CB's and none were less than 70 ms when tripped cold. Once you get to 10X current the trip value the time to trip is driven by the mechanical reaction to the trip current and more current is does not speed up tripping. The 50 ms for the contactor to open was based on measuring 3 different popular types using the widely recommended rectifier diode across the coil (see a different point for discussion on this) There are other conditions but all follow a similar pattern of not clipping/controlling the over voltage all the time and causing an excessively hi current pulse. In the 20th century current pulses were more common and the flight instruments did not have internal sensitive magnetometers that can be damaged with strong magnetic fields that are produced with multi hundred amp current pulse. The simple addition of one small resistor can control the current pulse and not defeat the circuit function. The elimination of this current pulse can be argued as not needed as there are other sources of current pulses but there should be no current pulses any where near the flight instruments. After all what is one more current pulse among friends? J Hardly nice, more like a bull in the china shop. Or perhaps a case of using a sledge hammers to kill flies? J Compare this to a 21st century solution where the OV is always clipped/controlled and then the alternator is taken off line. NO HV on the bus (outside DO-160 requirements), NO 400 amp current surge. Eric Jones has such a device right now. It is the result of what was learned during the "load dump" testing we performed last year. Also in the 21st century design there is NO hi current or current pulses near the instrument panel for anything from starter to landing gear to landing lights etc. The current and its protective devices are in the shortest path from the battery to the load, not thru a panel mounted electromechanical fuse or CB. The hi inrush current of hi powered devices is controlled with built in soft start logic. Why have a OVP that is brute force and subject to false tripping (see another point for discussion) when its not required, and in the field has a rather poor usage record as evidenced by the failure rate in RV's? As you know the Load dump testing program was the result of numerous Vans Aircraft alternators with rebuilt internal regulators failing. It has been suggested that Vans rebuilt regulators were somehow not as stout as others. There are over 4,000 Vans aircraft flying and Zero failures where there was no OVP device installed (Based on a Telecom with a senior person at Vans and none of the factory aircraft have ever had an OVP installed). 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. Another manufacturer of experimental aircraft engines etc has over 400 flying (many for 10+ years) with no failures of the ND alternator. There were 2 failures where the builder wanted the 'very best' and installed a B&C LR3 and modified ND alternator. After the second failure early in the life of the aircraft he went changed to an internally regulated ND alternator and has had no failures for the last 10 years Does this mean that the LR3 or the use of OVP devices is bad? Not at all, but its clear to us that the current product and or its installation or usage is faulty somewhere as something is wrong when all the reported alternator failures are only associated with OVP uses. The short circuit current results in the alternator going to FULL power and then when the short is removed the maximum possible load dump starts and is only terminated after 50 ms when the "B" lead contactor opens. Thus the system is first shorted out and then given a huge load dump and finally the alternator is taken off line. 50ms is quite long enough to damage equipment if the voltage is high enough. What's sad is all of the above is totally unnecessary and to suggest that the system can take it (because it MIGHT meet DO-160) is invalid in many cases. I have a reasonably modern panel with EFIS and moving map GPS and NOTHING I own is stated to pass any part of DO-160 and in fact the supply voltage limits (in some cases) are well inside DO-160 requirements. DO-160 may be applicable in the expensive products but one must not assume what you have installed meets any part of DO-160 much less all of it. If one simply used the above data it's a logical conclusion that adding an OVP of any common type causes failures and dramatically. Alternator regulators in modern automobiles are designed with internal safety circuits that prevent over voltage operation (except in the very rare pass transistor shorting). The probably of a modern battery failing open is many, many times higher. Spare prop bolts anyone J Seriously total engine failure and or propeller failures are far more frequent. Perhaps its time to forget about a rare failure whose attempts at protection have caused dozens of failures that otherwise would not have happened? Our testing shows that the best method of preventing OV is to first try to turn off the alternator using the field control lead (present and works on ND internal regulated alternators) only if this fails to work should the "B" lead be opened. This combined approach is the ultimate solution and is likely overkill. Just controlling the ND regulator lead is 99.99999% of the solution (in my opinion to be sure) but its simple and has no high currents to switch etc. Paul ________________________________ Message 6 _____________________________________ Time: 01:12:30 PM PST US From: "Paul Messinger" Subject: Re: AeroElectric-List: RE: [subaruaircraft] Re: CV Report on Ind Mod Failure --> AeroElectric-List message posted by: "Paul Messinger" I can help if you can wait until mid year when the 21st century design is completed and flight proven. There will be complete schematics etc and likely major modules available at that time. The major difference is my design has an optional second alternator and dual active engine management systems vs. a single tricked out OEM system. you are not forced to do anything as its completely modular but there will be complete end to end schematics with options. My contract is for a complete system but its not proprietary or exclusive. I can and will provide a universal system but intended for automotive derived experimental engines IE truly electrically dependent. I am sure Eric Jones will be a source for some of the components for those who do not want to build them for themselves. Also the company I have the contract with will be selling major modules that are universal in use. For a box that controls power to the various components in the aircraft where the load current is 20 amps or less. 2-3 dozen circuits with solid state switches etc internally you simply wire the power and control each function with a panel switch. Similar module for the main batteries/starter/alternator etc. Other modules as needed or than can be included in a couple of box designs. I am not doing all this work just for a one of a kind requirement as all of us can benefit with modern highly reliable and smart electrical systems. Paul ----- Original Message ----- From: "Brian Meyette" Subject: AeroElectric-List: RE: [subaruaircraft] Re: CV Report on Ind Mod Failure > --> AeroElectric-List message posted by: "Brian Meyette" > > > As someone who does not plan to use the EXPBUS in my Eggenfellner > installation, I would be most interested in something specific that Bob > could put together. There was a lot of talk on the Eggenfellner list > awhile > back about someone designing a replacement for the EXPBUS, but it didnt > materialize. I plan to use a combination of modified versions of Bobs > existing layouts and a couple of the Hyperion components. Anything that > Bob could put together as a complete, professional layout for the > Eggenfellner FWF (all-electric, one alternator, dual batteries, with full > backup, switchover, and protection) would be just great. > brian > expecting my STi in just a couple more weeks! > http://brian76.mystarband.net/RV-7Ahome.htm > > > -----Original Message----- > From: B Tomm [mailto:fvalarm@rapidnet.net] > To: 'subaruaircraft@yahoogroups.com' > Subject: RE: [subaruaircraft] Re: CV Report on Ind Mod Failure > > Gary, > > Thanks for the thoughtful reply. I'm sure Bob would be more than happy to > adapt an electrical layout for the EGG package. That is essentially what > Z-19 is. The only major mod that I can think of is putting the batteries > aft of the baggage (RV7A H6). I have already talked to him about this but > not finalized the details yet. I'll copy this email to Bob for comment. > > Bevan > > -----Original Message----- > From: Gary Newsted [SMTP:fcs@jlc.net] > To: subaruaircraft@yahoogroups.com > Subject: [subaruaircraft] Re: CV Report on Ind Mod Failure > > > I should point out that it is CV's optional enunciator module that I > have trouble with. The EXP is fine for what it does. > > When I started working on the electrical design, I was given the EXP > as a starting point. That is, take this design and make it work for > us, improve it where you can, but most importantly, make it > consistent. I feel that this has been achieved, and credit goes to > many people in this newsgroup for contributing their expertise. > > The install guide presents an airworthy adaptation of the EXP for > Eggenfellner engines, and tries to make the installation clear and > simple. If you follow the guide, you will have a modern, airworthy > system which is easy to operate and easy for us to diagnose should it > ever give you trouble. I occasionally pick on people who deviate > from this design, not because the design is perfect, but because I > believe consistency is at the very root of the success of > Eggenfellner packages. > > Let's face it, the thing that will bring down a Subaru will be fuel > or electrical, so these two systems must be consistent, with lots of > eyes reviewing these designs. One failure impacts all of us. > > Several times we have tossed around the pros and cons > of "conventional" electrical designs, of which Aeroelectrics are a > good example. I have not pursued this, although others have. In my > eyes, conventional designs leave too many doors open which could > result in inconsistency and even dangerous installations. If some > qualified individual wanted to invest the time and energy into > perfecting and thoroughly documenting a conventional design > specifically for the Eggenfellner engines, I think Jan would support > the effort (in spirit anyway). > > If you are a long ways away from wiring, don't rush into your > decision either. There just might be better things coming soon. > > > ADVERTISEMENT > click here > oups/S=1705063107:HM/EXP=1110662276/A=2593423/R=0/SIG=11el9gslf/*http://www. > netflix.com/Default?mqso=60190075> > > > _____ > > * To visit your group on the web, go to: > http://groups.yahoo.com/group/subaruaircraft/ > > * To unsubscribe from this group, send an email to: > subaruaircraft-unsubscribe@yahoogroups.com > > > Service . > > -- > No virus found in this outgoing message. > Checked by AVG Anti-Virus. > > > ________________________________ Message 7 _____________________________________ Time: 01:15:30 PM PST US From: "Paul Messinger" Subject: Re: AeroElectric-List: Points for discussion OVP/correction --> AeroElectric-List message posted by: "Paul Messinger" Sorry the Capital "J" is supposed to be a smiley face. I work in word and then copy into email. ----- Original Message ----- From: "Paul Messinger" Subject: AeroElectric-List: Points for discussion OVP > --> AeroElectric-List message posted by: "Paul Messinger" > > > Points for discussion OVP: Shorting/opening/limited current. > > > Sorry I did not have the normal time to wordsmith this so its somewhat > ruff > J ________________________________ Message 8 _____________________________________ Time: 01:38:13 PM PST US From: "Paul Messinger" Subject: Re: AeroElectric-List: Points for discussion OVP//more --> AeroElectric-List message posted by: "Paul Messinger" After reading my first subject post I have the following to suggest. Both Eric and I have often fallen into the trap of fixing the old vs. starting with a fresh idea. The increasingly common use of the ND internally regulated alternator along with modern regulators suggests the following approach to the OV issue. Use a hi quality ND rebuild alternator and / or a new one. One with a hi quality regulator that controls the field all the time. Use the proper size fuse in the "B" lead. I suggest that a 55 amp alternator should use a 60 amp as that fuse is designed to run forever at 60 amps and hopefully your load will hardly ever approach 55 amps. A failed and shorted alternator will supply more than rated current but lets not over due it. Use a OVP that opens the alternator field circuit. The 16.2V setting is fine. Eric Jones has this as a stock item. Please do not use a shorting crowbar here as that is cruel and unusual punishment to the electrons. Put a parallel set of 16V transorbs across the system bus between the fuse and the bus. The transorbs will clamp the bus to under 20V and blow the fuse if the failure is a real (quite rare)failure of the alternator that the field lead cannot control. Normally the field OVP will trip (having a 200 ms delay for load dump transients) and correct the problem. If this fails the transorbs will clamp the bus to a safe level and blow the fuse. The number of transorbs is under investigation (6-10 max expected worst case) but they are low cost ($0.41 each) in small quantities and Mouser has them in stock at this time. Look for 1N6276A or 1.5KE16A they are the same part functionally. The KISS principal wins another battle. Paul ________________________________ Message 9 _____________________________________ Time: 02:10:43 PM PST US From: "Charles Heathco" Subject: AeroElectric-List: Need known good mag --> AeroElectric-List message posted by: "Charles Heathco" I have deceided to go with one mag and one electronic for now on my RV6a, and both my mags are old and fear they are near end of service. I wonder if anyone might have a known good mag laying around from an elec conversion they want o sell. I now have bendix, could convert if have the wiring. my engine is O-320E2A Charlie heathco, reply to mail ________________________________ Message 10 ____________________________________ Time: 02:15:00 PM PST US From: B Tomm Subject: AeroElectric-List: Bob's approval electrical for Eggenfelner all electric system --> AeroElectric-List message posted by: B Tomm Yes I agree and I think many other will also be looking for "Bob and Jan approved" electrical system for Egg Subies. I suspect that it will be very close to Z-19 BUT I for one would sure like to hear from Bob and Jan on this. Bevan RV7A Fuse wiring soon Planning for Egg H6 -----Original Message----- From: Brian Meyette [SMTP:brianpublic@starband.net] Subject: AeroElectric-List: RE: [subaruaircraft] Re: CV Report on Ind Mod Failure --> AeroElectric-List message posted by: "Brian Meyette" As someone who does not plan to use the EXPBUS in my Eggenfellner installation, I would be most interested in something specific that Bob could put together. There was a lot of talk on the Eggenfellner list awhile back about someone designing a replacement for the EXPBUS, but it didnt materialize. I plan to use a combination of modified versions of Bobs existing layouts and a couple of the Hyperion components. Anything that Bob could put together as a complete, professional layout for the Eggenfellner FWF (all-electric, one alternator, dual batteries, with full backup, switchover, and protection) would be just great. brian expecting my STi in just a couple more weeks! http://brian76.mystarband.net/RV-7Ahome.htm -----Original Message----- From: B Tomm [mailto:fvalarm@rapidnet.net] Subject: RE: [subaruaircraft] Re: CV Report on Ind Mod Failure Gary, Thanks for the thoughtful reply. I'm sure Bob would be more than happy to adapt an electrical layout for the EGG package. That is essentially what Z-19 is. The only major mod that I can think of is putting the batteries aft of the baggage (RV7A H6). I have already talked to him about this but not finalized the details yet. I'll copy this email to Bob for comment. Bevan -----Original Message----- From: Gary Newsted [SMTP:fcs@jlc.net] Subject: [subaruaircraft] Re: CV Report on Ind Mod Failure I should point out that it is CV's optional enunciator module that I have trouble with. The EXP is fine for what it does. When I started working on the electrical design, I was given the EXP as a starting point. That is, take this design and make it work for us, improve it where you can, but most importantly, make it consistent. I feel that this has been achieved, and credit goes to many people in this newsgroup for contributing their expertise. The install guide presents an airworthy adaptation of the EXP for Eggenfellner engines, and tries to make the installation clear and simple. If you follow the guide, you will have a modern, airworthy system which is easy to operate and easy for us to diagnose should it ever give you trouble. I occasionally pick on people who deviate from this design, not because the design is perfect, but because I believe consistency is at the very root of the success of Eggenfellner packages. Let's face it, the thing that will bring down a Subaru will be fuel or electrical, so these two systems must be consistent, with lots of eyes reviewing these designs. One failure impacts all of us. Several times we have tossed around the pros and cons of "conventional" electrical designs, of which Aeroelectrics are a good example. I have not pursued this, although others have. In my eyes, conventional designs leave too many doors open which could result in inconsistency and even dangerous installations. If some qualified individual wanted to invest the time and energy into perfecting and thoroughly documenting a conventional design specifically for the Eggenfellner engines, I think Jan would support the effort (in spirit anyway). If you are a long ways away from wiring, don't rush into your decision either. There just might be better things coming soon. ADVERTISEMENT click here _____ * To visit your group on the web, go to: http://groups.yahoo.com/group/subaruaircraft/ * To unsubscribe from this group, send an email to: subaruaircraft-unsubscribe@yahoogroups.com Service . -- No virus found in this outgoing message. Checked by AVG Anti-Virus. ________________________________ Message 11 ____________________________________ Time: 02:15:06 PM PST US From: Mickey Coggins Subject: Re: AeroElectric-List: Points for discussion OVP//more --> AeroElectric-List message posted by: Mickey Coggins Hi, Where does one buy a *new* ND alternator? Thanks, Mickey > > The increasingly common use of the ND internally regulated alternator along > with modern regulators suggests the following approach to the OV issue. > > Use a hi quality ND rebuild alternator and / or a new one. One with a hi > quality regulator that controls the field all the time. > -- Mickey Coggins http://www.rv8.ch/ #82007 Wiring ________________________________ Message 12 ____________________________________ Time: 02:46:36 PM PST US From: "Paul Messinger" Subject: Re: AeroElectric-List: Points for discussion OVP//more --> AeroElectric-List message posted by: "Paul Messinger" There was a link on this list in the last couple of months. I lost my old email so I cannot help specifically but as I recall it was approx $250 for a 45 amp unit with LYC brackets and there were higher amp units available. Paul ----- Original Message ----- From: "Mickey Coggins" Subject: Re: AeroElectric-List: Points for discussion OVP//more > --> AeroElectric-List message posted by: Mickey Coggins > > > Hi, > > Where does one buy a *new* ND alternator? > > Thanks, > Mickey > > >> >> The increasingly common use of the ND internally regulated alternator >> along >> with modern regulators suggests the following approach to the OV issue. >> >> Use a hi quality ND rebuild alternator and / or a new one. One with a hi >> quality regulator that controls the field all the time. >> > > -- > Mickey Coggins > http://www.rv8.ch/ > #82007 Wiring > > > ________________________________ Message 13 ____________________________________ Time: 03:18:10 PM PST US From: "Kingsley Hurst" Subject: RE: AeroElectric-List: Points for discussion OVP/correction --> AeroElectric-List message posted by: "Kingsley Hurst" > Sorry the Capital "J" is supposed to be a smiley face. I work in word and then copy into email. Thanks for clarifying that Paul. Had me puzzled and I came to the conclusion it must have been short for "jest" as in "in jest" Regards Kingsley Hurst in Oz Do not archive ________________________________ Message 14 ____________________________________ Time: 04:45:19 PM PST US From: "Alex Peterson" Subject: RE: AeroElectric-List: Points for discussion OVP//more --> AeroElectric-List message posted by: "Alex Peterson" > Hi, > > Where does one buy a *new* ND alternator? > > Thanks, > Mickey http://www.niagaraairparts.com/, I believe theirs is a ND 40 amp. Alex Peterson RV6-A 584 hours Maple Grove, MN http://www.home.earthlink.net/~alexpeterson/ ________________________________ Message 15 ____________________________________ Time: 05:40:02 PM PST US Subject: Re: AeroElectric-List: Points for discussion OVP//more From: "John Schroeder" --> AeroElectric-List message posted by: "John Schroeder" On Mon, 14 Mar 2005 13:35:22 -0800, Paul Messinger wrote: > Put a parallel set of 16V transorbs across the system bus between the > fuse and the bus. > The number of transorbs is under investigation (6-10 max expected worst > case) > The KISS principal wins another battle. Paul - Somehow, this and the rest of your solution does not sound very simple to me. My problem here, as is usual for many of us OBAMers, is trying to implement the "new" solutions from the "idea" folks. How does one package these neat items? If there are pictures, schematics, PCB's or any other helpful hints in this regard, they would go a long way in convincing us that it is worth the effort. Putting 10-16 transorbs into a package and then "parallel" across the system buss sounds like an engineering problem of major significance - so much so, that I believe I'll stick with the "old" and make do with our perfectly good B&C regulators, stock alternator and backup alternator - all wired very close to a proven schematic (Z14). I like the dialogue and ferment of this forum so please keep the ideas coming. Just don't expect many of us to buy in without a lot more "engineering" of those ideas. Cheers, John -- ________________________________ Message 16 ____________________________________ Time: 05:52:33 PM PST US From: "John Swartout" Subject: RE: AeroElectric-List: Points for discussion OVP//more --> AeroElectric-List message posted by: "John Swartout" Bob Gross of RocketBoy Aircraft Products (www.f1-rocketboy.com/alternators.htm) recommends the Nippon Denso alternator (NSA Part No. ALT5021) for the 1987 Suzuki Samurai, available new, which is the same as a GEO Metro alternator (model year unknown) but has a v-belt pulley instead of the Metro's serpentine belt pulley. This 55 amp alternator is internally regulated to 14.5 volts. He says the Vans 35 amp alternator is called out for a 1978 Honda Civic. Would you regard the '87 Samurai alternator as a "modern" alternator, and, more to the point, the internal regulator as a "high quality regulator that controls the field all the time"? How does one determine these things when considering an alternator candidate? Thanks -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Paul Messinger Subject: Re: AeroElectric-List: Points for discussion OVP//more --> AeroElectric-List message posted by: "Paul Messinger" The increasingly common use of the ND internally regulated alternator along with modern regulators suggests the following approach to the OV issue. Use a hi quality ND rebuild alternator and / or a new one. One with a hi quality regulator that controls the field all the time. ________________________________ Message 17 ____________________________________ Time: 06:45:41 PM PST US From: "j1j2h3@juno.com" Subject: AeroElectric-List: LASAR/elecr ign --> AeroElectric-List message posted by: "j1j2h3@juno.com" Our club C-172 has LASAR ign on a carbureted 0-360 with a mogas STC. I find it starts far easier than standard mags. I like the fact that on a failure of the electronics, it reverts back to a standard mag (won't help for a broken rotor, though). No electrical backup needed. I have flown several other C-172's with 0-360's and standard mags and this one seems to be noticeably stronger. With standard mags, I had trouble leaning beyond peak without the engine running rough. With the LASAR it is no problem. Once I tried just for fun to see how far I could lean it. It went so lean that the falling EGT scared me and I quit, but it never did run rough or quit making power. I haven't done any long cross country flights, so I can't give you any firm figures on fuel usage, but it seems to be considerably better than the standard mags. The only data that I can give you is that on an hour of doing take-offs and landings, I use about 5.2 gallons. Using fuel savings data from Unison, I figure that the system will have paid for itself in a couple of years. We have been flying 10-12 hours per week for several years with no failures. Jim Hasper Franklin, TN RV7 - Just starting empennage (giving new meaning to the term slow-build) --> AeroElectric-List message posted by: "Charles Heathco" (snip) I have been going thru archives to try to evaluate elecronic ignition. Any LASAR defenders/happy users? ________________________________ Message 18 ____________________________________ Time: 08:05:47 PM PST US From: "Chris Byrne" Subject: Re: AeroElectric-List: P-Mag Electrical System --> AeroElectric-List message posted by: "Chris Byrne" Bob Thanks very much for you reply and the Revision 11 drawings. > Once you've decided to go with p-mags, the rest is pretty > simple. Unless you have some unusual "sleeper" in choice > of appliances, a 40A alternator will suffice nicely. Figure > Z-13/8 would be my first suggestion. See: Appreciate your help very much. Just want to confirm one thing. With the 40 Amp alt and the B@C 8 AMP alt I will have 48 AMPS avial. I guess my question is. Is the 8 AMP alt supplying to the circuit at all times or just in the case of a main alt outage. From my very limited understanding of the drawing the 8AMP is suppling to the circut at all times to make a total of 48AMPs. Chris Byrne Sydney ________________________________ Message 19 ____________________________________ Time: 08:18:14 PM PST US From: "John Swartout" Subject: RE: AeroElectric-List: Points for discussion OVP//more --> AeroElectric-List message posted by: "John Swartout" Paul, thanks for being patient with me and others on this list who are neophytes. Trying to follow along, learn something, and build a better airplane. Is the system you describe below approximately the same thing as the Zeftronics-built ASP101 Overvoltage protection sold by Niagara Airparts (described and schematicized here: http://www.niagaraairparts.com/ASP101-PIT%201.pdf), except that you add the transorbs? Thanks. John -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Paul Messinger Subject: Re: AeroElectric-List: Points for discussion OVP//more --> AeroElectric-List message posted by: "Paul Messinger" Use the proper size fuse in the "B" lead. I suggest that a 55 amp alternator should use a 60 amp as that fuse is designed to run forever at 60 amps and hopefully your load will hardly ever approach 55 amps. A failed and shorted alternator will supply more than rated current but lets not over due it. Use a OVP that opens the alternator field circuit. The 16.2V setting is fine. Eric Jones has this as a stock item. Please do not use a shorting crowbar here as that is cruel and unusual punishment to the electrons. Put a parallel set of 16V transorbs across the system bus between the fuse and the bus. The transorbs will clamp the bus to under 20V and blow the fuse if the failure is a real (quite rare)failure of the alternator that the field lead cannot control. Normally the field OVP will trip (having a 200 ms delay for load dump transients) and correct the problem. If this fails the transorbs will clamp the bus to a safe level and blow the fuse. The number of transorbs is under investigation (6-10 max expected worst case) but they are low cost ($0.41 each) in small quantities and Mouser has them in stock at this time. Look for 1N6276A or 1.5KE16A they are the same part functionally. The KISS principal wins another battle. Paul ________________________________ Message 20 ____________________________________ Time: 08:33:39 PM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: White Paper on Crowbar OV Protection --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" See: http://www.aeroelectric.com/articles/Crobar_OV_Protection/Crowbar_White_Paper.pdf Bob . . . ________________________________ Message 21 ____________________________________ Time: 08:34:58 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: P-Mag Electrical System --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 03:04 PM 3/15/2005 +1100, you wrote: >--> AeroElectric-List message posted by: "Chris Byrne" > > >Bob > >Thanks very much for you reply and the Revision 11 drawings. > > > Once you've decided to go with p-mags, the rest is pretty > > simple. Unless you have some unusual "sleeper" in choice > > of appliances, a 40A alternator will suffice nicely. Figure > > Z-13/8 would be my first suggestion. See: > > >Appreciate your help very much. > >Just want to confirm one thing. With the 40 Amp alt and the B@C 8 AMP alt I >will have 48 AMPS avial. >I guess my question is. Is the 8 AMP alt supplying to the circuit at all >times or just in the case of a main alt outage. It's for standby. The largest full up IFR load I've calculated to date was 27 amps for an all-electric system. An L-40 or similar alternator supplies this load with plenty of heatroom for battery charging. The SD-8 is intended for standby use in supporting the e-bus in case of main alternator failure and is NOT operated in conjunction with the main alternator. > From my very limited understanding of the drawing the 8AMP is suppling to >the circut at all times to make a total of 48AMPs. The SD-8 is normally OFF except when the main alternator is not available. Bob . . . ________________________________ Message 22 ____________________________________ Time: 08:43:01 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Points for discussion OVP//more --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 01:35 PM 3/14/2005 -0800, you wrote: >--> AeroElectric-List message posted by: "Paul Messinger" > >After reading my first subject post I have the following to suggest. > >Both Eric and I have often fallen into the trap of fixing the old vs. >starting with a fresh idea. > >The increasingly common use of the ND internally regulated alternator along >with modern regulators suggests the following approach to the OV issue. > >Use a hi quality ND rebuild alternator and / or a new one. One with a hi >quality regulator that controls the field all the time. I've wrestled with this issue for years. The term "high quality" is simply not quantifiable. >Use the proper size fuse in the "B" lead. I suggest that a 55 amp alternator >should use a 60 amp as that fuse is designed to run forever at 60 amps and >hopefully your load will hardly ever approach 55 amps. A failed and shorted >alternator will supply more than rated current but lets not over due it. How so? For several years we used to supply JJN- and JJS series fuses for alternator b-lead protection. A 60-amp fuse was offered for both 40 and 60 amp alternators. Several years into the activity, folks started complaining about popping the 60A fuse on an L-60 installation. After some invstigation we found that the fuses popped when the owner tried to charge a dead battery by running the engine. The cold L-60 would easily open a 60A fast fuse. >Use a OVP that opens the alternator field circuit. The 16.2V setting is >fine. Eric Jones has this as a stock item. Please do not use a shorting >crowbar here as that is cruel and unusual punishment to the electrons. "Cruel and unusual" is not quantified. Went to the bench this afternoon and duplicated some work I did at Electro-Mech about 25 years ago. See white paper report at: http://www.aeroelectric.com/articles/Crobar_OV_Protection/Crowbar_White_Paper.pdf >Put a parallel set of 16V transorbs across the system bus between the fuse >and the bus. The transorbs will clamp the bus to under 20V and blow the fuse >if the failure is a real (quite rare)failure of the alternator that the >field lead cannot control. Normally the field OVP will trip (having a 200 ms >delay for load dump transients) and correct the problem. If this fails the >transorbs will clamp the bus to a safe level and blow the fuse. The number >of transorbs is under investigation (6-10 max expected worst case) but they >are low cost ($0.41 each) in small quantities and Mouser has them in stock >at this time. If you set the voltage regulator for 16.3 volts with the transorbs in place, will they take the system off line? Bob . . . ________________________________ Message 23 ____________________________________ Time: 08:52:04 PM PST US From: "Mitch Faatz" Subject: AeroElectric-List: Electrical System Loads (was P-Mag) --> AeroElectric-List message posted by: "Mitch Faatz" > >I guess my question is. Is the 8 AMP alt supplying to the circuit at all > >times or just in the case of a main alt outage. > > It's for standby. The largest full up IFR load I've calculated > to date was 27 amps for an all-electric system. An L-40 or similar > alternator supplies this load with plenty of heatroom for battery That's not including any lights, right? From what I've gathered so far, lighting is *huge*: strobes (8A) + nav (9A) = 17A, throw in a couple landings lights (4.5A each) for a draw of 26A on final for lights alone. If lights are off in my case: Garmin 430 (not transmitting - 3.3A), Transponder (1.5A), Intercom (0.5A), Autopilot (3.6A), Alternator Field (4A) and couple gauges and an engine monitor (2A) = ~15A, or 23A if you've got pitot heat on. If lights were on, you'd have a healthy draw of 41A, or 49A with pitot heat. Does that sound right? Mitch Faatz RV-6A Finish Kit (wiring diagram, actually) Auburn, CA ________________________________ Message 24 ____________________________________ Time: 09:47:30 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Electrical System Loads (was P-Mag) --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 08:51 PM 3/14/2005 -0800, you wrote: >--> AeroElectric-List message posted by: "Mitch Faatz" > > > >I guess my question is. Is the 8 AMP alt supplying to the circuit at all > > >times or just in the case of a main alt outage. > > > > It's for standby. The largest full up IFR load I've calculated > > to date was 27 amps for an all-electric system. An L-40 or similar > > alternator supplies this load with plenty of heatroom for battery > >That's not including any lights, right? From what I've gathered so far, >lighting is *huge*: strobes (8A) + nav (9A) = 17A, throw in a couple >landings lights (4.5A each) for a draw of 26A on final for lights alone. This is why the very first step in configuring an electrical system is to do a load analysis and decide what kinds of things need to be on at the same time under various flight modes. Strobes are usually 5-6 amps peak and average less than 3. Nav lights are usually 2a per bulb but you can use Eric Jone's LED kits and push what's normally a 6a system down to something on the order of 3A. Landing lights are temporary loads but yes, 9A is a fair continuous running load value. You don't need pitot heat any time lights are on (clear of clouds) and vice versa. Autopilots don't generally draw max loads except in turbulence and then the average loads are less than max. Alternator field may or may not be part of running loads . . . the maufacturer of an alternator knows that it needs to support it's own field and the output rating of the alternator should be IN ADDITION to field requirements. It will be maxed out only at low RPM and full electrical load. Most alternators cruise at under 1 amp. >If lights are off in my case: Garmin 430 (not transmitting - 3.3A), >Transponder (1.5A), Intercom (0.5A), Autopilot (3.6A), Alternator Field (4A) >and couple gauges and an engine monitor (2A) = ~15A, or 23A if you've >got pitot heat on. > >If lights were on, you'd have a healthy draw of 41A, or 49A with pitot heat. > >Does that sound right? Nope . . . that's why the load analysis is so important. Lots of builders are carrying around oversized alternators that increase cost of ownership while not contributing to performance of the airplane. Bob . . .