---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sat 02/19/11: 5 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:30 AM - Re: First Start Alternator Woes (Robert L. Nuckolls, III) 2. 08:25 AM - Looking for Cool (Digital) Ammeter (CardinalNSB@aol.com) 3. 09:38 AM - Re: Looking for Cool (Digital) Ammeter (Jeff Luckey) 4. 04:42 PM - AC ground prong question (Lincoln Keill) 5. 06:01 PM - Voltage Regulator Problem (frank3) ________________________________ Message 1 _____________________________________ Time: 06:30:31 AM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: Re: First Start Alternator Woes At 05:42 AM 2/19/2011, you wrote: >Thanks Bob. > >This morning, I got the ALT to come on line. I connected up two >30Amp blade fuses in parallel on a fully charged battery and voila, >14.5 volts on the BUS. > >Is it possible the drained battery was pulling more AMPs than the >ANL40 and 20AMP fuse could handle? Sure. But I'm mystified as to why the ANL40 got into trouble. Here's the spec sheet on ANL current limiters: http://aeroelectric.com/Mfgr_Data/Fuses_and_Current_Limiters/Bussman/ANL_Specs.pdf Note that these are VERY ROBUST protective devices intended to carry rated currents + overloads for protracted periods of time. I.e. these are not intended to be fast acting fuses. They're intended to clear HARD faults in power distribution systems. My best guess is that your 'ANL40' may have been a poorly crafted clone that behaved more like a fuse than a current limiter. Get a 'real' ANL of any current rating from 40 to 60 an you'll probably fix the problem. If you can't find a qualified ANL, consider an automotive in-line fuse holder for the MAX series of plastic fuses. http://aeroelectric.com/Mfgr_Data/Fuses_and_Current_Limiters/Bussman/MAXI_Specs.pdf http://aeroelectric.com/Pictures/Fuses/Fuse_Holders/MaxiFuse_Holder.jpg Install a MAX70 or MAX80 fuse in the holder. I charged of in the direction of 'failed diodes' assuming that your 'anl' fuses were performing to specs. But your question is right on point. A 60A amp alternator charging a dead battery will go flat-out and quite often will trip a 60A breaker. My assumption was out in the weeds. http://www.aeroelectric.com/articles/anl/anlvsjjs.html http://www.aeroelectric.com/articles/never_again.html The 60A breaker on the B-lead of 60A alternators in tens of thousands of GA aircraft are DESIGNED to nuisance trip under precisely the conditions you hypothesized. Get the right b-lead protection installed and I think you're good to go. By the the way, paralleled fuses is a useful experiment but not a permanent fix. Bob . . . >Subject: Re: Fwd: First Start Alternator Woes > >At 06:34 PM 2/18/2011, you wrote: > >Dear Bob, > > > >I did a first start of my RV7 EI-EEO last weekend and the alternator > >did not come on line. > > > >I have an L-60 and LR3 regulator from B&C. Wiring diagram attached. > > > >On working through B&Cs LR3 troubleshooting all voltages looked > >good, then checked the Field connector. Connectors were pushed back. > >Great we found the problem. No joy. Then went through all the checks > >again. The ANL40 that I have installed was blown. We put a blade > >fuse holder with a 20Amp fuse in its place. Fired her up, switched > >on the Alt field (no electrics on expect for the EFIS) and the 20Amp > >fuse blew almost immediately. > > > >What are the modes that could produce this behaviour? Would a 20AMP > >fuse always blow? I see now that the ANL40 should have been a 60ANL, > >but why would the ANL40, with such low loads. If the battery was > >low, would that be the reason. > > The only thing that will blow an ANL > b-lead fuse is shorted diodes in the > alternator. A normally working alternator > cannot open its own b-lead protection. Bob . . . ________________________________ Message 2 _____________________________________ Time: 08:25:47 AM PST US From: CardinalNSB@aol.com Subject: AeroElectric-List: Looking for Cool (Digital) Ammeter _http://www.aircraftextras.com/AG6.htm_ (http://www.aircraftextras.com/AG6.htm) is similar. ________________________________ Message 3 _____________________________________ Time: 09:38:29 AM PST US From: "Jeff Luckey" Subject: RE: AeroElectric-List: Looking for Cool (Digital) Ammeter Thanks for the link. Not really what I had in mind but I had forgotten about Aircraft Extras. _____ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of CardinalNSB@aol.com Sent: Saturday, February 19, 2011 08:20 Subject: AeroElectric-List: Looking for Cool (Digital) Ammeter http://www.aircraftextras.com/AG6.htm is similar. ________________________________ Message 4 _____________________________________ Time: 04:42:14 PM PST US From: Lincoln Keill Subject: AeroElectric-List: AC ground prong question After a recent trip to Japan, I am very glad I am building Z-13/8 that only uses 14V DC power because I realize how little I understand AC...perhaps s omeone can enlighten me. -Questions were generated while trying to charge my laptop in the hotel. -I know that Japan uses 50Hz and 100V AC power ( which my AC adapter (more properly called a "transformer-rectifier" I belie ve) could handle according to the attached label). -I also knew that most such small appliance AC adapters (such as cell phones, iPods, etc.) don't have a third (ground) prong on their male plug end. -However, the AC adap ter for my laptop DOES have this third prong which created a problem, since the outlets in the room had only two female receptacles (the longer "neutr al" slot and the shorter "hot" slot). - The hotel provided an adapter that allowed me to plug my three prong adapte r into the two prong outlet, but then I wondered "Should I even be doing th is? -Will sparks fly? -Will my AC adapter die a slow death from undervo ltage? -Am I okay as long as I don't peruse the AEC forum listings while sitting in the bathtub? -Does my AC adapter even need this third ground p rong, and if not, why don't I just dremel it off...I mean, my cell phone ch arger doesn't have the ground prong, so why not?" Someone told me that the Japanese AC current is two-phase, which seemed odd to me, but I remember in my C-130 days we had electrical buses that were s ingle-phase AC and some that were three-phase AC so I guess a two-phase AC circuit wouldn't be out of the question....is this why there is no ground p rong slot on my hotel outlet? -Is the Japanese electrical grid hopelessly out of date and do thousands of people die here each year from electrocuti on (hard to believe)? -The most likely explanation would seem to be that the Japanese system is just as safe as ours (even without ground plugs) but I simply don't understand the fundamentals of AC electricity. Long story short...I plugged in my computer using the adapter and it worked fine....but why? -Can anyone explain or give me a link to a reference th at will explain all this? Do Not Archive Lincoln Keill Anyone- Someone had once told me that- ________________________________ Message 5 _____________________________________ Time: 06:01:11 PM PST US Subject: AeroElectric-List: Voltage Regulator Problem From: "frank3" I have a 912ULS with the Ducati regulator wired into the Z16 diagram that I have been flying for three years. Today on run-up I noted low voltage ( -------- Frank Read this topic online here: http://forums.matronics.com/viewtopic.php?p=331577#331577 ------------------------------------------------------------------------------------- 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.