---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Tue 10/13/09: 26 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:21 AM - Required Length of Fusible Links (mikeeasley) 2. 06:46 AM - Re: Control Stick/Flap Switches (Eric M. Jones) 3. 06:57 AM - Re: Diodes vs. Bi-Directional Zeners for Contactors (Eric M. Jones) 4. 09:40 AM - Re: Battery capacity testing (Ed Holyoke) 5. 09:51 AM - Re: Diodes vs. Bi-Directional Zeners for Contactors (Robert L. Nuckolls, III) 6. 09:59 AM - Re: Diodes vs. Bi-Directional Zeners for Contactors (user9253) 7. 10:01 AM - Re: Required Length of Fusible Links (Robert L. Nuckolls, III) 8. 10:10 AM - Re: Control Stick/Flap Switches (Tim Olson) 9. 10:43 AM - Flap Switch Location (John Markey) 10. 10:43 AM - Re:Battery Capacity Testing (Richard Dudley) 11. 11:13 AM - Re: Control Stick/Flap Switches (Bill Mauledriver Watson) 12. 11:13 AM - Re: Flap Switch Location (Bruce Gray) 13. 11:42 AM - Re: Diodes vs. Bi-Directional Zeners for Contactors (Robert L. Nuckolls, III) 14. 11:52 AM - Re: Re:Battery Capacity Testing (Carlos Trigo) 15. 12:26 PM - Re: Wig-Wagging LED lamps (Speedy11@aol.com) 16. 12:26 PM - Re: Bi-Directional Zeners for Contactors (gmcjetpilot@yahoo.com) 17. 12:43 PM - Re: Wig-Wagging LED lamps (Speedy11@aol.com) 18. 12:58 PM - Re: Re: Bi-Directional Zeners for Contactors (mikeeasley) 19. 01:24 PM - Re: Re: Diodes vs. Bi-Directional Zeners for Contactors (Robert L. Nuckolls, III) 20. 01:27 PM - Re: Re:Battery Capacity Testing (Richard Dudley) 21. 01:33 PM - Re: Battery capacity testing (Robert L. Nuckolls, III) 22. 01:38 PM - Re: Wig-Wagging LED lamps (XeVision) 23. 03:44 PM - Re: Re: Bi-Directional Zeners for Contactors (Bob Meyers) 24. 06:33 PM - Re: Control Stick/Flap Switches (Speedy11@aol.com) 25. 06:33 PM - Re: Control Stick/Flap Switches (Speedy11@aol.com) 26. 07:18 PM - 2 Alternator Split System (al38kit) ________________________________ Message 1 _____________________________________ Time: 06:21:11 AM PST US From: mikeeasley Subject: AeroElectric-List: Required Length of Fusible Links B&C sells fusible links that are intended to be 5-6" long. Do they have to be that long? Do you need to allow any space around them for the heat when they smoke? If you're protecting a #22 wire, do you go to #26 in the fusible link? Thanks, Mike Easley Colorado Springs ________________________________ Message 2 _____________________________________ Time: 06:46:12 AM PST US Subject: AeroElectric-List: Re: Control Stick/Flap Switches From: "Eric M. Jones" A note on control stick switches: Make sure they are environmentally sealed for the harshest jungle-like conditions encountered under sweaty palms. -------- Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge, MA 01550 (508) 764-2072 emjones@charter.net Read this topic online here: http://forums.matronics.com/viewtopic.php?p=267735#267735 ________________________________ Message 3 _____________________________________ Time: 06:57:46 AM PST US Subject: AeroElectric-List: Re: Diodes vs. Bi-Directional Zeners for Contactors From: "Eric M. Jones" Bob N., you are truly to be admired for the limitless energy you have put into this subject. I don't know how you do it. I sell "SnapJacks" bi-directional zeners for putting across the coils of relays, inductors, and especially contactors--as recommended by Tyco, Potter and Brumfield, Megavac, Kilovac, and virtually all other relay engineers who have ever looked at the problem. But hey, you could be right! One lone voice in the wilderness. I admire you. "Every act of conscious learning requires the willingness to suffer an injury to one's self-esteem...." -Thomas Szasz -------- Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge, MA 01550 (508) 764-2072 emjones@charter.net Read this topic online here: http://forums.matronics.com/viewtopic.php?p=267737#267737 ________________________________ Message 4 _____________________________________ Time: 09:40:49 AM PST US From: Ed Holyoke Subject: Re: AeroElectric-List: Battery capacity testing Howdy, I recently subjected the Concord RG-25XC in our RV to an unscheduled deep discharge test by way of leaving the E-buss switch on for a couple of days on the ramp at West Yellowstone. We jump started the airplane with a car, but as soon as the cables were removed, there was nothing on the panel. Apparently the battery was so dead that the alternator didn't kick in. I failed to notice if the alternator was running with the jumper cables connected, but I think it must have been. All the normal lights and gages were working prior to disconnection. We called National Aircraft Parts Association and had them send over a "snowmobile battery", a Yaesu 18ah sized like a PC680 and that got us going. We hauled the dead Concorde RG-25XC home and I charged it up. I did a capacity check on it with a West Mountain Radio CBA II tester down to 10.5 volts, just as I do at annual, and it did pretty well. It produced 28 ampere hours at a 4amp draw. Not bad for a 24AH battery! When tested at the most recent annual inspection, it put out just over 30, so it may be slightly degraded, but still very good. We only need about 16AH to be able to keep the electronic ignition and some of the more important bits of avionics working 'till we run out of gas, so this battery still has a ways to go before replacement. I'll save the 18AH Yaesu for other uses. Pax, Ed Holyoke > The battery is subject to no more stresses than > situations where you've jump started your car > because the headlights were left on. Would the > battery last longer had it never been subjected > to the deep discharge event? Arguably yes . . . but > by so small a value as to be difficult to measure > and totally insignificant to your operational perceptions. > But it's not an undue stress on the ship's accessories. > They are all qualified to perform to nameplate ratings > when the airplane was awarded a type certificate. > > ________________________________ Message 5 _____________________________________ Time: 09:51:30 AM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: Re: Diodes vs. Bi-Directional Zeners for Contactors At 08:56 AM 10/13/2009, you wrote: Bob N., you are truly to be admired for the limitless energy you have put into this subject. I don't know how you do it. See philosophical snippet in my signature . . . I sell "SnapJacks" bi-directional zeners for putting across the coils of relays, inductors, and especially contactors--as recommended by Tyco, Potter and Brumfield, Megavac, Kilovac, and virtually all other relay engineers who have ever looked at the problem. But hey, you could be right! One lone voice in the wilderness. I admire you. Eric my friend. You've missed the point of this discussion since day-one. This isn't about Bob N. or anyone else being "right" or "wrong" . . . it's about understanding simple-ideas and crafting a recipe for success conforming to design goals. Yes, the folks at all the big houses have the opportunity to know more about their products than anyone else. Certainly there was a time that was true. Except for Microswitch, virtually all of my requests for investigative assistance in a relay or switch failure over the last 15 years produced a young, wet-behind- the-ears visitor from the company who was probably a recent graduate. He/she was assigned support on the legacy products. A sure bet. No? The legacy products have decades of market history. Nothing can go wrong . . . go wrong . . . go wrong. They had never designed a thing, never conducted a failure analysis, and had no customer or field service experience. They were seldom accompanied by a learned mentor. This sad condition is being repeated throughout a once capable and competent community of suppliers to US industry. I could have treated these experiences as either a burden or opportunity. Given that the issues were costing my employer $millions$, it was good that I was willing and able to rise to the OPPORTUNITY to observe, discover, learn and ultimately teach. More often than not, my discoveries produced facts of performance that the factory support folks didn't understand. Further, it was NOT in their best interests to admit that their capabilities were found lacking. Put yourself in their shoes . . . you're right out of college. First job with Mister Big Relays and Contactors, Inc. You walk back into your office and tell your boss, "The customer knows more about the product I understand or was able to offer." You (and others) have cited the writings by employees of Mr. Big and (without understanding the significance of their words) have parroted them back to support some opinion. Further, you and others have evolved products base on the same cursory citations. I have endeavored to test, measure, observe, and analyze the behaviors switches, relays and contactors for the purpose of achieving understanding and offering the best-I-know-how-to-do advice. For quit a few years, I was well paid by my employers to carry out such studies. If you find my offerings lacking, how about offering your own analysis of the repeatable experiments I've conducted and/or the data collected therefrom? I'll have to look back over our writings on this topic but I can't recall that you have ever offered a data point discovered by yourself backed up with documentation on a repeatable experiment. While I attempt to offer analysis and advice based on demonstrable fact, you seem content to whack me about the head and shoulders with Mr. Big's technical papers that may contain errors of fact or interpretation. It may be true that the paper on small mil-spec relays is not directly related to our discussions about large contactors used on a OBAM light aircraft. "One voice in the wilderness" ????? This isn't a wilderness my friend. It's the universe. The whole universe runs on physics. Each concept in physics is a simple-idea. Combining those simple-ideas into useful recipes for success is what skilled product development is all about. I've not said that the latest-greatest spike suppression techniques do not perform as advertised. What I have said is that these products are being marketed based on FEAR of loss of RELIABILITY. I have endeavored to deflect worries about reliability by encouraging confidence in failure tolerant design. Confidence built on understanding that applying the latest- and-greatest will produce no observable benefit for the applications we're developing. If you have a vision about how simple-ideas can be more effectively used, let's talk about it. If you find any error of interpretation of the data I've gathered and posted, nobody would be more pleased to know about it than I. Please don't remake this into a Friday night wrestling exhibition between between myself and Mr. Big's writers . . . or anyone else. Bob . . . ________________________________ Message 6 _____________________________________ Time: 09:59:28 AM PST US Subject: AeroElectric-List: Re: Diodes vs. Bi-Directional Zeners for Contactors From: "user9253" TYCO's document at http://relays.tycoelectronics.com/appnotes/app_pdfs/13c3311.pdf says, "It is the velocity of the armature that is most affected by coil suppression. If the suppressor provides a conducting path, thus allowing the stored energy in the relay's magnetic circuit to decay slowly, the armature motion will be retarded and the armature may even temporarily reverse direction." TYCO's document seemed credible until the above paragraph. How can a relay start to drop out, then reverse direction? Where does the power come from to do this? Using a diode for arc suppression, the relay will start to drop out when the voltage decays to some point less than 12 volts. In order for the relay to reverse direction, the voltage will have to increase. But how could it increase? The voltage has already decayed to the point where the relay drops out, and the diode is still shorting out what little energy is left. It is common knowledge that a relay requires a higher voltage to pull in than to drop out. TYCO is suggesting the impossible. Making that ridiculous statement makes one question the validity of the whole document. The table showing the drop out times of various suppression devices does not make it clear exactly what time interval was measured. Was it the interval from when power to the coil was first shut off to the time that the contacts were fully opened? If so, that time is irrelevant to arcing of the relay contacts. The only time interval of concern is from when the relay contacts first start to open until they are open far enough to quench the arc. The important thing is, how much longer do relay contacts arc when using diode compared to using a zener? And is that time difference significant in our application? I agree with Bob. The TYCO article is BS. Mike Easley and Colyn Case are concerned about the arc-suppression diode shorting out across the main contactor. A 22awg wire can be used from the contactor fat terminal to the coil terminal, then a 18awg from the other side of the coil into the cockpit. In case of an unlikely short, the 22awg wire will burn open first, keeping smoke on the engine side of the firewall. Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=267757#267757 ________________________________ Message 7 _____________________________________ Time: 10:01:36 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Required Length of Fusible Links At 08:12 AM 10/13/2009, you wrote: >B&C sells fusible links that are intended to be 5-6" long. Do they >have to be that long? Do you need to allow any space around them >for the heat when they smoke? If you're protecting a #22 wire, do >you go to #26 in the fusible link? Fusible links should not be used to generally replace fuses or circuit breakers. They are used only when a ROBUST feeder protection is needed. These might be properly called Micro-ANL current limiters. If you're considering an application other than one illustrated in the Z-figures, let's discus it here on the List. 6" is a good length for meeting the thermal model that controls the fusing event. You COVER them in a material capable of containing the fusing event. Hence the fiberglas/silcone jacket in the B&C kit. #26 wire is too fragile to be practical for a/c wiring. #24 is marginal but okay in applications illustrated. I've often thought I should not have introduced the fusible link to the OBAM aircraft community but then, it's just a collection of simple-ideas with specific but LIMITED applicability to our design goals. Let's not start scattering these guys around the airplane. If you need an isolated, single strand not conveniently protected by a fuse at the bus, then consider an in-line fuse holder. http://aeroelectric.com/Pictures/Fuses/Fuse_Holders/ifh-2.jpg Bob . . . --------------------------------------- ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) --------------------------------------- ________________________________ Message 8 _____________________________________ Time: 10:10:54 AM PST US From: Tim Olson Subject: Re: AeroElectric-List: Control Stick/Flap Switches Absolutely agree with that one Bruce! A co-policy I have is that all control moving circuits should have breakers, not fuses, because you want them pull-able. Tim Olson - RV-10 N104CD Bruce Gray wrote: > > It's a bad idea to put control of any function on a control stick that > if inadvertently activated could jeopardize the safety of the aircraft. > > Bruce > www.Glasair.org > > -----Original Message----- > From: owner-aeroelectric-list-server@matronics.com > [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Bill > Bradburry > Sent: Monday, October 12, 2009 1:02 PM > To: aeroelectric-list@matronics.com > Subject: AeroElectric-List: Control Stick/Flap Switches > > > > I have a flap switch wired thru a couple of relays to raise and lower > the > flaps. The switch is a double pole double throw type. > I just installed an Infinity grip and there is a single throw single > pole > switch on the grip that I would like to wire into the system to also > control > the flap. I realize the in order to use either switch, the other switch > will have to be off. > The problem is that I am electron deficient and have no idea of how to > wire > this up. Any help from the list would be greatly appreciated. > > Bill B > > ________________________________ Message 9 _____________________________________ Time: 10:43:30 AM PST US From: John Markey Subject: AeroElectric-List: Flap Switch Location The gentleman who built my wonderful Glasair II put the flap switch next to the throttle. While keeping my hand on the throttle in the pattern, I can readily activate the flap up/down with my thumb. Otherwise, it is offset enough to not be in the way. The 3-axis trim is on the stick, and this is plenty to adjust with my left hand, especially on base and short final. Bottom line: I agree with the previous post; keep the flap off of the stick. John ________________________________ Message 10 ____________________________________ Time: 10:43:30 AM PST US From: "Richard Dudley" Subject: AeroElectric-List: Re:Battery Capacity Testing For what it is worth, here are my battery endurance procedure experiences. For the first and second annual condition inspections of my RV-6A, I decided to follow the procedure of replacing my 17/18 AH RG battery rather than do an endurance check. The battery had cost only $50 and I treated it as expendable. Meanwhile, after the second condition inspection, I conducted experiments on the replaced battery. Based on measured current draw of the avionics and instruments that I considered necessary in the event of an alternator failure I used automobile lights in parallel to simulate a load equivalent to the expected current drain.. I confirmed the current drawn with that load. Then I monitored the voltage and the time until the battery reached 11 volts. It turned out that with a current of about 9 amps, I had 1.5 hours endurance on a battery that had been used for a year. This pretty much agreed with the published endurance curves for that battery. For the third condition inspection, I decided to test the year-old battery in place in the aircraft. To accomplish this, I switched on the "endurance" bus, turned on the avionics and instruments that I considered essential after alternator failure. I then monitored voltage, the avionics and time. The result was similar to the earlier simulation with the auto lamps: the avionics went out at about 1.5 hours. Since this test was over in an hour and a half, only a voltmeter and clock were needed to gather data and the battery was re-charged in a reasonable time via my external power jack. This convinced me that the battery could be used until the next condition inspection. Should anyone wonder during the second year about the battery endurance, the test could be conducted at any time with the expenditure of a couple of hours. Regards, Richard Dudley ________________________________ Message 11 ____________________________________ Time: 11:13:46 AM PST US From: Bill Mauledriver Watson Subject: Re: AeroElectric-List: Control Stick/Flap Switches Tim, I realize that I've followed the same policy in my fuse-centric panel. Or at least I think I have.... So to compare notes: I have 4 pull-able/reset-able breakers in my panel: - (2) for the 2 B&C alternator controllers for proper operation of the crow bar OV protection - (1) for my flaps with FPS - (1) for my AP The rest are all fuses on a 2 bus Z-14 I didn't have a policy per se, but my thinking for the 2 latter fuses was: - the flap motor could be overpowered by extension at high speeds - so a reset-able capability is desirable since it is a control surface - The pull-able breaker gives me an emergency off switch for the autopilot I should add that I have the Safety Trim system which has a trim shut off and other safety related functions. Tim Olson wrote: > > Absolutely agree with that one Bruce! A co-policy I have is > that all control moving circuits should have breakers, not > fuses, because you want them pull-able. > > Tim Olson - RV-10 N104CD > > > Bruce Gray wrote: >> >> >> It's a bad idea to put control of any function on a control stick that >> if inadvertently activated could jeopardize the safety of the aircraft. >> >> Bruce >> www.Glasair.org >> -----Original Message----- >> From: owner-aeroelectric-list-server@matronics.com >> [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Bill >> Bradburry >> Sent: Monday, October 12, 2009 1:02 PM >> To: aeroelectric-list@matronics.com >> Subject: AeroElectric-List: Control Stick/Flap Switches >> >> >> >> I have a flap switch wired thru a couple of relays to raise and lower >> the >> flaps. The switch is a double pole double throw type. >> I just installed an Infinity grip and there is a single throw single >> pole >> switch on the grip that I would like to wire into the system to also >> control >> the flap. I realize the in order to use either switch, the other switch >> will have to be off. >> The problem is that I am electron deficient and have no idea of how to >> wire >> this up. Any help from the list would be greatly appreciated. >> >> Bill B >> >> > > ________________________________ Message 12 ____________________________________ Time: 11:13:46 AM PST US From: "Bruce Gray" Subject: RE: AeroElectric-List: Flap Switch Location Yep, that's where I put mine also. Bruce www.Glasair.org -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of John Markey Sent: Tuesday, October 13, 2009 1:37 PM Subject: AeroElectric-List: Flap Switch Location The gentleman who built my wonderful Glasair II put the flap switch next to the throttle. While keeping my hand on the throttle in the pattern, I can readily activate the flap up/down with my thumb. Otherwise, it is offset enough to not be in the way. The 3-axis trim is on the stick, and this is plenty to adjust with my left hand, especially on base and short final. Bottom line: I agree with the previous post; keep the flap off of the stick. John ________________________________ Message 13 ____________________________________ Time: 11:42:38 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Diodes vs. Bi-Directional Zeners for Contactors I'm interested in comments on the relative merits of using diodes vs. bi-directional zeners. Also, the failure modes of both devices. And how to size the bi-directional zeners to minimize the chance of a failure, especially a short failure. What would happen if either were fail shorted due to high voltage? Excellent question . . . and the answer goes directly to countless studies and adjustment of design goals for the purpose of producing an ACCEPTABLE reliability factor (generally stated in failures per flight hour). Any time we can deduce that the failure rate is better than 1 in 10 to the minus 6 failures per flight hour (i.e. 1,000,000 flight hours per failure), the guys who worry about such things relax a lot. Now, does such a determination say that all components under study will last 1,000,000 hours? No, the testing and calculations tell us that the AVERAGE failure rate for a large population of identical components is 1,000,000 hours per failure or better. If you have a device fail in 500,000 hours, then other components of that population will have to do better than 1,000,000 hours for the average to hold. Experience shows us that robust and otherwise new components which fall victim to errors of manufacturing process will fail early (infant mortality) . . . especially if operated at or just above extreme stress ratings for that device. This process is called "screening" and is the basis for Mil-Std-883 qualified components favored in critical military and space programs. The screening process is designed to precipitate infant mortality failures. Even then, some folks paid to worry will sandbag their design goals by telling suppliers to DE-RATE their already screened 883 components by some factor. Resistors will be de-rated to 1/2 power. Capacitors operated at 1/2 rated voltage, etc. etc. I've smiled when reading the purchase specs driven by such worries. Virtually every product failure over which I was given direction turned out to be an error in design or process, not a failure of component to meet requirements for which it was properly designed and qualified. It seems like the guy turning the wrenches is still the riskiest ingredient in the recipe. So let's potential for stress induced failure of a diode across the coil of a contactor. See: http://www.fairchildsemi.com/ds/1N/1N4001.pdf For the most part, we're building 14v airplanes with a sprinkling of 28v. Okay, a 50v rated diode will have a 2x headroom in a 28v airplane, 3.5x in a 14v airplane. For a few cents more, one COULD install a 600V rated diode. Man, talk about de-rating! On the conduction side of the study, the typical 1A diode (1N400x series) is designed and qualified to conduct 1A at a max voltage drop of 1.1 volts. Okay, this is 1.1 watts of heat being dumped out in that diminutive glass or plastic package. Now, we never SEE that 1.1 volts under our anticipated usage. But let's take worst case. CAPACITORS charge to some voltage will deliver that SAME voltage at potentially HIGH current during the discharge cycle. INDUCTORS charged to some current will deliver that SAME current at potentially HIGH voltage during their discharge cycle. Now, here's an el-cheeso battery contactor running coil current of .6 to 1.0 amps. When the circuit is broken, we can expect a PULSE of current at no more than 1.0 amps. Further, the duration of that current is on the order of 200 milliseconds ramping down from 1.0 amps to zero. Let's assume an AVERAGE of 0.5 Amps over 200 milliseconds with a maximum voltage drop of 1.1 volts. Hmmm . . . that's a worst case value of 110 milljoules of energy over 0.2 seconds dumped into a device DESIGNED to dissipate 1100 millijoules of energy every second for an indefinite period of time. May I suggest that this too is an exceedingly conservative de-rating philosophy? So while we're discussing potential failure modes for becoming either shorted or open, let us not loose our grip on probability of failure based on the expected stresses versus stresses defined by the device's design. Devices used for coil spike suppression are VERY lightly taxed and therefore exceedingly low failure rates. Short answer is that "sizing" of these components based on their electrical characteristics is a exercise in no-value-added-worrying. I prefer to size them for mechanical robustness as illustrated many places in my writing and illustrating. The beefier 1N5400 series devices are less likely to be damaged by over-enthusiastic wrench turning. Whether you use zeners-diode combos, bi-directional Transorbs, resistors, diodes, etc will have no observable effect on system reliability based on ratings. But beating the little guys up with wrench or hammer is another matter. The more valid worry is not WHAT you use but HOW you use it. Bob . . . --------------------------------------- ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) --------------------------------------- ________________________________ Message 14 ____________________________________ Time: 11:52:41 AM PST US From: "Carlos Trigo" Subject: RE: AeroElectric-List: Re:Battery Capacity Testing Perhaps a dumb question about a small detail, but to conduct these capacity tests, how did you measure the time, were you one and a half hours looking at the voltmeter to see when it reached the 11V? Carlos _____ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Richard Dudley Sent: ter=E7a-feira, 13 de Outubro de 2009 18:36 Subject: AeroElectric-List: Re:Battery Capacity Testing For what it is worth, here are my battery endurance procedure experiences. For the first and second annual condition inspections of my RV-6A, I decided to follow the procedure of replacing my 17/18 AH RG battery rather than do an endurance check. The battery had cost only $50 and I treated it as expendable. Meanwhile, after the second condition inspection, I conducted experiments on the replaced battery. Based on measured current draw of the avionics and instruments that I considered necessary in the event of an alternator failure I used automobile lights in parallel to simulate a load equivalent to the expected current drain.. I confirmed the current drawn with that load. Then I monitored the voltage and the time until the battery reached 11 volts. It turned out that with a current of about 9 amps, I had 1.5 hours endurance on a battery that had been used for a year. This pretty much agreed with the published endurance curves for that battery. For the third condition inspection, I decided to test the year-old battery in place in the aircraft. To accomplish this, I switched on the "endurance" bus, turned on the avionics and instruments that I considered essential after alternator failure. I then monitored voltage, the avionics and time. The result was similar to the earlier simulation with the auto lamps: the avionics went out at about 1.5 hours. Since this test was over in an hour and a half, only a voltmeter and clock were needed to gather data and the battery was re-charged in a reasonable time via my external power jack. This convinced me that the battery could be used until the next condition inspection. Should anyone wonder during the second year about the battery endurance, the test could be conducted at any time with the expenditure of a couple of hours. Regards, Richard Dudley ________________________________ Message 15 ____________________________________ Time: 12:26:20 PM PST US From: Speedy11@aol.com Subject: AeroElectric-List: Re: Wig-Wagging LED lamps My apology, Mr/Ms/Mrs dblumel. I meant no offense to XeVision. You make an excellent product. In fact, I likely would have bought it at Sun n Fun several years ago except that the guy working your booth was quite rude. So, I went to the Precise Flight booth and found an opposite response. I bought their product. I don't know where Precise Flight buys their bulbs, but I do know they work very well for my application (RV-8A). I do plan to upgrade to the 50 or 70W version. I do not work for Precise Flight nor have any working or financial relationship with them. My LED recognition lights can easily be seen 5 miles away, but they are very directional. At that distance they have to pointed at you to be seen. Within 1 mile, they can be seen about 30-40 degrees off center. If one designs reflective material into the lamp assembly, the angle-off visibility improves. Stan Sutterfield XeVision developed and made available 50 watt HID in early 2005 and 75 watt HID about 2 years ago for special applications. Both the 50 and 75 watt HID from XeVision are used in the Eurocopter line of Helicopters within their TC and as an upgrade. Note: the industry std. is to rate this HID technology based on Watts output (to the bulb), not using input to the ballasts as the rating. This is a common problem with Asian made HID products and their wattage ratings. The ONLY quality HID bulbs in the 35-75 watt range are made in Europe. The Asians including Korea are a long way from matching the QC, life and performance provided by Philips, Osram (Sylvania) and GE HID bulbs. ________________________________ Message 16 ____________________________________ Time: 12:26:21 PM PST US From: gmcjetpilot@yahoo.com Subject: AeroElectric-List: Re: Bi-Directional Zeners for Contactors The EV200 is a different animal from the ubiquitous-coil/solenoid/contact or. I did lots of research on this. Notice the activation and latched current? Very small. Yo u don't need diodes. The EMF part, I'm-not sure about. The diode on the classic c ontactor is to suppress the voltage spike from the collapsing field, thus protecting th e switch from arching and-reduced life and failure. - I don't recall the details, but the EV200 uses different mechanical geometr y and electro- magnetism activation and scheme that is more efficient, while maintaining r idiculous power specs. - I also looked at the cost v benefit. On a Lancair, cost no object, EV200 wh y not. For the average home built, even my RV7 the standard contactors are fine. Still the price of the EV200 has come way down; it's an attractive option now, especially for savi ng weight. It does not weigh a lot less it self versus a standard contactor, but it uses about +0.50 amps less to stay latched. For guys trying to fly day/night deluxe VFR with a li ghter wight-30 or 40 amp alternator, every 0.50 amp counts. - These are my opinions. If you don't like them, request a refund for what yo u paid for it. - Cheers. - - >From: mikeeasley >Subject: AeroElectric-List: Diodes vs. Bi-Directional Zeners for Contactor s >I'm building a new power grid for a customer and the research on contactor s ended >up with some digging on the diodes that we use across the coils of the con tactors, >and whether they're necessary.- We're using a couple Tyco Kilovac EV200s >and since they have pigtail wires instead of terminals, it's tougher to in stall >the diodes.- Tyco says we don't need "back EMF protection" with the EV20 0s. >But we are also using the LEV100 contactors, which do need the back EMF pr otection.=0A=0A=0A ________________________________ Message 17 ____________________________________ Time: 12:43:46 PM PST US From: Speedy11@aol.com Subject: AeroElectric-List: Re: Wig-Wagging LED lamps In a word - no. LEDs are still relatively expensive - especially when the word airplane is associated with it. I was able to accomplish what you described, but at a cost of $600+ Prices are dropping, but not rapidly. However, consider using 12v MR-16 bulbs. They are lightweight, cheap, bright, easy to install, and readily available. The major drawback is heat. They get VERY hot. You would need to ventilate them. They get much hotter than LEDs, which themselves must be use heat sinks. There are many types or MR-16s - some with IR lenses, some without, some that let the IR out thru the reflector, some that send all IR out the front, some that are blue tinted to give a blue light, 50w, 35w, 75w, spot, flood, wide ... lots of variables. Before buying the LEDs, I had settled on the 65W, 12 degree spot MR-16 bulb with a plan to add a 12v computer fan to help cool it. Stan Sutterfield "Cheap", let's say $50 dollars for each LED assy so $100 total (both wings). "Bright", let's say easily noticed wig-wagging from at least 2-3 miles away, within a 20-30 deg angle from head-on. Ralph Finch Davis, California RV-9A QB-SA ________________________________ Message 18 ____________________________________ Time: 12:58:21 PM PST US From: mikeeasley Subject: Re: AeroElectric-List: Re: Bi-Directional Zeners for Contactors The Tyco EV200 has built-in back EMF suppression according to the engineer at Tyco Kilovac. I didn't ask him what kind of suppression, but he confirmed that it wasn't necessary to have any external suppression. The LEV series needs external suppression. The EV series has a circuit that reduces coil amperage once it closes also. Mike Easley Colorado Springs In a message dated 10/13/09 13:27:27 Mountain Daylight Time, gmcjetpilot@yahoo.com writes: The EV200 is a different animal from the ubiquitous coil/solenoid/contactor. I did lots of research on this. Notice the activation and latched current? Very small. You don't need diodes. The EMF part, I'm not sure about. The diode on the classic contactor is to suppress the voltage spike from the collapsing field, thus protecting the switch from arching and reduced life and failure. I don't recall the details, but the EV200 uses different mechanical geometry and electro- magnetism activation and scheme that is more efficient, while maintaining ridiculous power specs. I also looked at the cost v benefit. On a Lancair, cost no object, EV200 why not. For the average home built, even my RV7 the standard contactors are fine. Still the price of the EV200 has come way down; it's an attractive option now, especially for saving weight. It does not weigh a lot less it self versus a standard contactor, but it uses about +0.50 amps less to stay latched. For guys trying to fly day/night deluxe VFR with a lighter wight 30 or 40 amp alternator, every 0.50 amp counts. These are my opinions. If you don't like them, request a refund for what you paid for it. Cheers. >From: mikeeasley >Subject: AeroElectric-List: Diodes vs. Bi-Directional Zeners for Contactors >I'm building a new power grid for a customer and the research on contactors ended >up with some digging on the diodes that we use across the coils of the contactors, >and whether they're necessary. We're using a couple Tyco Kilovac EV200s >and since they have pigtail wires instead of terminals, it's tougher to install >the diodes. Tyco says we don't need "back EMF protection" with the EV200s. >But we are also using the LEV100 contactors, which do need the back EMF protection. ________________________________ Message 19 ____________________________________ Time: 01:24:46 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Diodes vs. Bi-Directional Zeners for Contactors At 11:58 AM 10/13/2009, you wrote: > >TYCO's document at >http://relays.tycoelectronics.com/appnotes/app_pdfs/13c3311.pdf >says, "It is the velocity of the armature that is most affected by >coil suppression. If the suppressor provides a conducting path, thus >allowing the stored energy in the relay's magnetic circuit to decay >slowly, the armature motion will be retarded and the armature may >even temporarily reverse direction." > >TYCO's document seemed credible until the above paragraph. >I agree with Bob. The TYCO article is BS. Very astute observations sir. And they agree with my own . . . along with conditions I measured on the bench. Drop-out delay is strongly influenced by current decay in the coil when the armature is seated. Contact spreading velocity is a function of BOTH coil current AND the AIR-GAP in the magnetic path once the armature becomes unseated. An air gap in any magnetic pathway has a huge effect. Reverse direction? Yeah, right. So once you allow coil current to fall just enough to unseat the armature, the rate at which the armature accelerates is more strongly influenced by the air-gap than by decay in magnetic field. I WAS able to detect perhaps 2 or 3% increase in spreading velocity for "fancy" versus "hammer-n-tongs" coil suppression . . . too small to be significant terms of service life. I also used a fast 'scope to observe differences in arcing during the contact break without and then with various coil suppression techniques. Yes, there were differences. So small and so variable that I couldn't hang my hat on coil suppression as having any observable effect on service life of the CONTACTORS and LARGE RELAYS under investigation. These simple-ideas can be observed and combinational effects duplicated . . . as well they should be. It's the repeatable experiment that determines whether you have a souffle, scrambled-eggs and cheese, or garbage. Your attention to detail sir is commendable. Bob . . . ________________________________ Message 20 ____________________________________ Time: 01:27:26 PM PST US From: "Richard Dudley" Subject: Re: AeroElectric-List: Re:Battery Capacity Testing Hi Carlos, The short answer is: yes. I used a stop watch function on my wristwatch. In the first capacity tests with the dummy load of auto lamps, I checked the voltage at convenient intervals like 10 minutes until it approched 11 volts because I was unsure what to expect. I even plotted the data. When it started to change more rapidly I checked more often. From fully charged, around 12.7 volts to near 11 volts, the change is very slow. Near 11 volts, the decline is quite rapid. After I knew better what to expect, during the actual tests in the plane in the hangar, I just checked the voltage periodically and noted when the avionics failed. It was part of my condition inspection tests so, I had other things to do on the plane. There are plenty of fancier automated ways to test without personally monitoring. (Bob Nuckolls has published a timer that will count until the battery voltage drops to a predetermined voltage.) However, I felt that I could "squander" an hour and a half once a year looking at a voltmeter and my watch, and even multitasking with other tasks I had in the hangar. Regards, Richard ----- Original Message ----- From: Carlos Trigo To: aeroelectric-list@matronics.com Sent: Tuesday, October 13, 2009 2:44 PM Subject: RE: AeroElectric-List: Re:Battery Capacity Testing Perhaps a dumb question about a small detail, but to conduct these capacity tests, how did you measure the time, were you one and a half hours looking at the voltmeter to see when it reached the 11V? Carlos ------------------------------------------------------------------------- ----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Richard Dudley Sent: ter=E7a-feira, 13 de Outubro de 2009 18:36 To: aeroelectric-list@matronics.com Subject: AeroElectric-List: Re:Battery Capacity Testing For what it is worth, here are my battery endurance procedure experiences. For the first and second annual condition inspections of my RV-6A, I decided to follow the procedure of replacing my 17/18 AH RG battery rather than do an endurance check. The battery had cost only $50 and I treated it as expendable. Meanwhile, after the second condition inspection, I conducted experiments on the replaced battery. Based on measured current draw of the avionics and instruments that I considered necessary in the event of an alternator failure I used automobile lights in parallel to simulate a load equivalent to the expected current drain.. I confirmed the current drawn with that load. Then I monitored the voltage and the time until the battery reached 11 volts. It turned out that with a current of about 9 amps, I had 1.5 hours endurance on a battery that had been used for a year. This pretty much agreed with the published endurance curves for that battery. For the third condition inspection, I decided to test the year-old battery in place in the aircraft. To accomplish this, I switched on the "endurance" bus, turned on the avionics and instruments that I considered essential after alternator failure. I then monitored voltage, the avionics and time. The result was similar to the earlier simulation with the auto lamps: the avionics went out at about 1.5 hours. Since this test was over in an hour and a half, only a voltmeter and clock were needed to gather data and the battery was re-charged in a reasonable time via my external power jack. This convinced me that the battery could be used until the next condition inspection. Should anyone wonder during the second year about the battery endurance, the test could be conducted at any time with the expenditure of a couple of hours. Regards, Richard Dudley http://www.matronics.com/Navigator?AeroElectric-Listhttp://forums.matroni cs.comhttp://www.matronics.com/contribution ________________________________ Message 21 ____________________________________ Time: 01:33:27 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Battery capacity testing Ed and Richard, Good job gentlemen! A fine thinker and craftsman of repeatable experiments once opined: "When you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind; it may be the beginning of knowledge, but you have scarcely in your thoughts advanced to the state of Science." -Lord Kelvin- Bob . . . --------------------------------------- ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) --------------------------------------- ________________________________ Message 22 ____________________________________ Time: 01:38:52 PM PST US Subject: AeroElectric-List: Re: Wig-Wagging LED lamps From: "XeVision" Stan, my name is Dan (Male). Your comment is rather "interesting" in light of the fact that we have NEVER had a booth at Sun N Fun, in fact we (nor I or any employee) have never even attended Sun N Fun. So I am not sure how we could have been rude to you or anyone else at "our booth". Precise Fight uses Osram (Sylvania) brand D1S HID bulbs for their 35 watt applications. This bulb is made in Germany. Dan [quote="Speedy11(at)aol.com"]My apology, Mr/Ms/Mrs dblumel. I meant no offense to XeVision. You make an excellent product. In fact, I likely would have bought it at Sun n Fun several years ago except that the guy working your booth was quite rude. So, I went to the Precise Flight booth and found an opposite response. I bought their product. I don't know where Precise Flight buys their bulbs, but I do know they work very well for my application (RV-8A). I do plan to upgrade to the 50 or 70W version. I do not work for Precise Flight nor have any working or financial relationship with them. My LED recognition lights can easily be seen 5 miles away, but they are very directional. At that distance they have to pointed at you to be seen. Within 1 mile, they can be seen about 30-40 degrees off center. If one designs reflective material into the lamp assembly, the angle-off visibility improves. Stan Sutterfield > XeVision developed and made available 50 watt HID in early 2005 and 75 watt HID > about 2 years ago for special applications. > > Both the 50 and 75 watt HID from XeVision are used in the Eurocopter line of Helicopters > within their TC and as an upgrade. > > Note: the industry std. is to rate this HID technology based on Watts output (to > the bulb), not using input to the ballasts as the rating. This is a common problem > with Asian made HID products and their wattage ratings. > > The ONLY quality HID bulbs in the 35-75 watt range are made in Europe. The Asians > including Korea are a long way from matching the QC, life and performance provided > by Philips, Osram (Sylvania) and GE HID bulbs. > > [b] -------- LED still has a long way to go to compete with HID as a landing light. This is true in terms of total lumens and reach (distance). Read this topic online here: http://forums.matronics.com/viewtopic.php?p=267800#267800 ________________________________ Message 23 ____________________________________ Time: 03:44:25 PM PST US From: Bob Meyers Subject: Re: AeroElectric-List: Re: Bi-Directional Zeners for Contactors That .50 amp savings was why I put one in my Aerovee powered Sonex with a 20 amp alternator. I had already mounted a fine cheap one from B&C but I had an opportunity to get one cheap and replace it. "Scotty, I need more power" Bob Meyers Building Sonex 982SX Web Site Index http://meyersfamily.org/Sonex982.html On Oct 13, 2009, at 2:24 PM, gmcjetpilot@yahoo.com wrote: > The EV200 is a different animal from the ubiquitous coil/solenoid/ > contactor. I did lots of > research on this. Notice the activation and latched current? Very > small. You don't > need diodes. The EMF part, I'm not sure about. The diode on the > classic contactor is > to suppress the voltage spike from the collapsing field, thus > protecting the switch from arching and reduced life and failure. > > I don't recall the details, but the EV200 uses different mechanical > geometry and electro- > magnetism activation and scheme that is more efficient, while > maintaining ridiculous power > specs. > > I also looked at the cost v benefit. On a Lancair, cost no object, > EV200 why not. For the > average home built, even my RV7 the standard contactors are fine. > Still the price of the > EV200 has come way down; it's an attractive option now, especially > for saving weight. It > does not weigh a lot less it self versus a standard contactor, but > it uses about +0.50 amps > less to stay latched. For guys trying to fly day/night deluxe VFR > with a lighter wight 30 or > 40 amp alternator, every 0.50 amp counts. > > These are my opinions. If you don't like them, request a refund for > what you paid for it. > > Cheers. > > > >From: mikeeasley > >Subject: AeroElectric-List: Diodes vs. Bi-Directional Zeners for > Contactors > > >I'm building a new power grid for a customer and the research on > contactors ended > >up with some digging on the diodes that we use across the coils of > the contactors, > >and whether they're necessary. We're using a couple Tyco Kilovac > EV200s > >and since they have pigtail wires instead of terminals, it's > tougher to install > >the diodes. Tyco says we don't need "back EMF protection" with the > EV200s. > >But we are also using the LEV100 contactors, which do need the back > EMF protection. > > ________________________________ Message 24 ____________________________________ Time: 06:33:01 PM PST US From: Speedy11@aol.com Subject: AeroElectric-List: Re: Control Stick/Flap Switches Bill, If you can do it, Jim's setup is ideal. Stan Sutterfield I have my flap switch on the throttle and trim on the stick. Works great for me Jim James Robinson Glasair lll N79R Spanish Fork UT U77 ________________________________ Message 25 ____________________________________ Time: 06:33:01 PM PST US From: Speedy11@aol.com Subject: AeroElectric-List: Re: Control Stick/Flap Switches Bill, There is nothing wrong with or dangerous about putting your flap switch on the control stick. However, one must use due diligence when activating a switch on the stick when one has more than one switch on the stick. For example, I have flap switch, trim switch and starter switch all on the top of my stick. I also have PTT, AP disconnect and smoke on the stick. However, I've flown fighters for years and I'm comfortable with HOTAS. It would be easy to accidentally activate the flaps when reaching for the trim (I disable my starter button with a switch when flying). If the flaps are accidentally started down, you simply switch them back up immediately. So, while it is not dangerous to have flaps (or any other switch) on the stick, it might be prudent to put it on the panel or near the throttle if you are a private pilot who trained in aircraft that used a panel mounted flap switch. If you prefer to have switches on the stick, then wire it that way. I would tell you how I wired mine, but mine is unique and may not fit your needs. Is there another builder nearby that can help? If you can't find help, contact me directly (off the forum) and I'll talk you through my installation. Stan Sutterfield My 2 cents-- Keep the stick simple and place the flap switch on the panel. Peter On Mon, Oct 12, 2009 at 1:27 PM, Bruce Gray wrote: > > It's a bad idea to put control of any function on a control stick that > if inadvertently activated could jeopardize the safety of the aircraft. > > Bruce > www.Glasair.org > > -----Original Message----- > From: owner-aeroelectric-list-server@matronics.com > [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Bill > Bradburry > Sent: Monday, October 12, 2009 1:02 PM > To: aeroelectric-list@matronics.com > Subject: AeroElectric-List: Control Stick/Flap Switches > > > > I have a flap switch wired thru a couple of relays to raise and lower > the > flaps. The switch is a double pole double throw type. > I just installed an Infinity grip and there is a single throw single > pole > switch on the grip that I would like to wire into the system to also > control > the flap. I realize the in order to use either switch, the other switch > will have to be off. > The problem is that I am electron deficient and have no idea of how to > wire > this up. Any help from the list would be greatly appreciated. > > Bill B ________________________________ Message 26 ____________________________________ Time: 07:18:20 PM PST US Subject: AeroElectric-List: 2 Alternator Split System From: "al38kit" As I design my system, I have a question regarding which alternator to use to power the main flight/nav instruments...I'm planning an IFR all electric panel. I do plan to have back up instruments on the other buss. I have the small B&C 20 amp gear driven alternator, and a 60 amp PP belt driven. This will be going on an IO520. I plan to run the busses, with an interconnect in the event of failure of one of the alternators. Which alternator should I plan to power the "more critical" buss? Does it matter...? Al Read this topic online here: http://forums.matronics.com/viewtopic.php?p=267842#267842 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message aeroelectric-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/AeroElectric-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/aeroelectric-list Browse Digests http://www.matronics.com/digest/aeroelectric-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.