---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sun 04/08/18: 1 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 09:14 AM - Re: Charging Issue (Robert L. Nuckolls, III) ________________________________ Message 1 _____________________________________ Time: 09:14:29 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Charging Issue At 07:15 PM 4/7/2018, you wrote: >I completed my RV-10 in July of 2015. I also >have a Plane Power 60A main alternator and a 30A >alternator as the back up. And I am having the >exact same symtoms. Plane Power tells me I >should be getting 14.3 to 14.5 volts on the main >and slightly less than that on the backup >alternator. Should the main alternator output >drop below that of the backup, the backup will >take over. Fact is The main puts out 13.4V to >13.6V=C2 and the back running by itself puts out >about the same. Running both together might get >me 13.7V. I bought a new 60A alternator and it >did the same. I had both the new and the old >tested at a starter/alternator shop and they >tested to Plane Power specs at 14.5V. My power >distribution system is a modified Bob Knuckles >Z-13-8 System. I have noticed there are other >RV-10 owners having the same issue. I am David Duperron=C2 616-485-5555. What size is the b-lead wiring from altenrator to the bus . . . and where are you attaching the b-lead feeder to the system? Just for grins, try a temporary b-lead feeder directly from alternator to the battery terminal of the starter contactor . . . 6AWG or larger is good. The alternators in question SENSE 'bus voltage' AT THE B-LEAD TERMINAL. Modern internal regulators are quite accurate and consistent. As others have suggested, you first need to know what the alternator's output voltage is . . . given consistent results with two alternators, odd are that the alternator is fine and you're getting voltage drops in the path between b-terminal and your measurement point. Virtually all the Z-figures show 4AWG feeders from b-terminals via shortest path to the power systems FAT wires. The reason for this is to minimize losses in this high current pathway . . . a good thing to do whether the alternator is internally or externally regulated. Bob . . . ------------------------------------------------------------------------------------- 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.