---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Mon 07/12/10: 6 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 08:01 AM - Re: Deceptive Voltage? (Robert L. Nuckolls, III) 2. 08:33 AM - Engine ground (John Tvedte) 3. 09:34 AM - Re: Another battery maintainer/charger question (David LLoyd) 4. 09:53 AM - OSH '10 Options (John Cox) 5. 06:46 PM - Re: Engine ground (Robert L. Nuckolls, III) 6. 06:51 PM - Microair 760 bench test fixture (Robert L. Nuckolls, III) ________________________________ Message 1 _____________________________________ Time: 08:01:28 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Deceptive Voltage? At 05:36 PM 7/11/2010, you wrote: 7/11/2010 Hello Bob Nuckolls and other Electrical Gurus, Suppose you ran your battery down by spinning your first time to be started O-540 Lycoming engine with the starter in order to preoil the engine in your nearly finished RV-10. And maybe you did some other things that ran the battery down. Then you connected your small amperage output battery charger to the battery and you attempted to start the Shower of Sparks equipped engine without success. The engine was cranked OK, but the starting vibrator just was not putting out. A check of the system voltage in appropriate points with a separate volt meter while cranking the engine showed 13 plus volts. This number appears bogus. A battery is incapable of delivering energy at more than about 12.5 volts lightly loaded . . . a few amps. Given that most batteries offer an internal resistance on the order of .007 to .010 ohms, a 200A starter draw would be expected to drop the battery terminal voltage by perhaps 2 volts. So a terminal voltage of 10.5 or lower is expected. Is it possible that the voltage being seen was in fact the voltage being put out by the battery charger as it attempted to recharge the run down battery, but the amperage being put out by the run down battery and battery charger together just was not enough current flow to run the starting vibrator as well as crank the engine? No, if the engine cranked at some speed you would EXPECT to start it, then the battery is fine. The shower-of-sparks system is designed to do two things: (1) increased intensity of the sparking energy by offering a repeating train of battery-supported sparks and (2) DELAYING the delivery of ANY sparks until just after TDC such that potential for kickback is eliminated. If your engine cranks but doesn't start, the battery is fine and the SOS system is suspect. This article might be of value in your quest for making all things right with the world: http://www.aeroelectric.com/articles/Shower-of-Sparks/ShowerOfSparks.pdf Bob . . . //// (o o) ===========o00o=(_)=o00o======== < Go ahead, make my day . . . > < show me where I'm wrong. > ================================ ________________________________ Message 2 _____________________________________ Time: 08:33:47 AM PST US From: John Tvedte Subject: AeroElectric-List: Engine ground When connecting a ground to the engine - I am wondering if braided bonding straps and flexible wire (aka welding wire) are equally applicable? I am also wondering how much slack is appropriate regards length. For example if I measure 15" from firewall stud to engine stud - how much e xtra length should used to allow for engine movement? John ________________________________ Message 3 _____________________________________ Time: 09:34:54 AM PST US From: "David LLoyd" Subject: Re: AeroElectric-List: Another battery maintainer/charger question Ed, The little maintainer should be dead silent. I suspect the step down transformer inside the unit is bad. I would try to return it to the store for an exchange or send it back to the manuf. They should be good about replacing it. The float voltage should be approx. 13.1 to 13.4 volts. There are probably internal adjustments "if" you can pop the case. However, if the transformer is faulty/vibrates at 60/120 Hz. then it needs to be swapped with a good one. David _________________________________________________________ ----- Original Message ----- From: "Neal George" Sent: Sunday, July 11, 2010 5:13 PM Subject: RE: AeroElectric-List: Another battery maintainer/charger question > > Ed - > My little Schumacher 1562 1.5-amp charger/maintainer is silent - at least, > if it makes any noise, I've never noticed it, even in the wee hours with > the > house & shop quiet. > > Neal > N8ZG > > -----Original Message----- > From: owner-aeroelectric-list-server@matronics.com > [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of edleg > > Everything works fairly well except for two troubling things: > 1. the maintainer/charger is very loud, even in the maintainer mode -- > actually louder than my other two regular 6/2 amp and 10/2 amp battery > chargers. > 2. the "float" voltage that is maintained is at 12.96 vdc as measured by > two > different digital (fluke brand) volt meters. Seems a little bit low when > reading the other posts here. > > So... Bob and the other electron experts: is there a relatively > (physically) > small maintainer/charger that doesn't always sound like a loud battery > charger (oxymoron???) when in the maintainer mode, and is the float > voltage > high enough? > > Thanks, > > -Ed- > NX6ED > > > ________________________________ Message 4 _____________________________________ Time: 09:53:17 AM PST US Subject: AeroElectric-List: OSH '10 Options From: "John Cox" I am again offering B&B style beds in the classic brick Oshkosh house that I rent each year for EAA members. The house comes with central air for those hot or humid nights, newly remodeled kitchen, big screen HDTV (with video input for your daily shots), fresh towels, cold beer and toiletry service. I will transport campers each day To/From Airventure 2010. Available from Saturday, July 24th through Sunday, August for $250 per occupant = nine nights and days. Send me an email with your phone number and I will promptly call back to secure your First class accomodations. It is way beyond camping on the field in a tent or staying in a Dorm at the UW-OSH. John Cox johnwcox at pacificnw.com ________________________________ Message 5 _____________________________________ Time: 06:46:30 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Engine ground At 10:31 AM 7/12/2010, you wrote: >When connecting a ground to the engine I am >wondering if braided bonding straps and flexible >wire (aka welding wire) are equally applicable? yes > >I am also wondering how much slack is appropriate regards length. enough slack that there is no tension and/or sharp bends adjacent to end terminals. > >For example if I measure 15 from firewall stud >to engine stud how much extra length should >used to allow for engine movement? It isn't the enginge that moves a lot, it's the nice floppy wire that moves. Add a couple or three inches and don't ask wire to change directions sharply next to the ends. Bob . . . ________________________________ Message 6 _____________________________________ Time: 06:51:33 PM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: Microair 760 bench test fixture I've placed a Microair 760 bench test fixture up on Ebay as item number 150466479723 This can be used to operate your radio on the bench out of the airplane . . . or in the airplane independently of ship's wiring. Handy diagnostic/ test tool for this radio. If you have an xcom 760 radio, this test fixture can be easily adapted to operate that radio by re-arranging some wires in the connector. Bob . . . //// (o o) ===========o00o=(_)=o00o======== < Go ahead, make my day . . . > < show me where I'm wrong. > ================================ ------------------------------------------------------------------------------------- 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.