---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Fri 03/23/07: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 03:06 AM - Re: Out of town for a couple of days (Bill Settle) 2. 06:54 AM - Re: Wire size dilemma () 3. 07:01 AM - Re: Wire size dilemma () 4. 09:04 AM - Re: What did I do wrong? (John Burnaby) ________________________________ Message 1 _____________________________________ Time: 03:06:46 AM PST US From: Bill Settle Subject: Re: AeroElectric-List: Out of town for a couple of days YEEHAAA!!!! Been looking forward to this. Can't wait! Bill Settle Winston-Salem, NC -8 Wings > > From: "Robert L. Nuckolls, III" > Date: 2007/03/22 Thu PM 10:27:49 EST > To: aeroelectric-list@matronics.com > Subject: AeroElectric-List: Out of town for a couple of days > > > Dr. Dee and I are climbing aboard the heavy iron bird for > the Winterville, North Carolina seminar next Saturday and > Sunday. We'll be off line until Tuesday. If anyone wants > to attend this presentation, you can just show up. You don't > need a reservation. See: > > http://aeroelectric.com/seminars/Winterville.html > > > > Bob . . . > > ---------------------------------------- > ( IF one aspires to be "world class", ) > ( what ever you do must be exercised ) > ( EVERY day . . . ) > ( R. L. Nuckolls III ) > ---------------------------------------- > > > > > > ________________________________ Message 2 _____________________________________ Time: 06:54:58 AM PST US Subject: RE: AeroElectric-List: Wire size dilemma From: Alan, Also, if you have questions about impedance and length, take a look at and try one of the worksheets from Jim's engineering page. His worksheet takes out a lot of the guesswork. http://www.rst-engr.com/rst/jimsdata/index.html -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Thursday, March 22, 2007 11:24 PM Subject: Re: AeroElectric-List: Wire size dilemma --> At 09:42 PM 3/22/2007 -0400, you wrote: > > >Ok, so I'm planning on a dual alt/batt 24v setup for a Lancair legacy. >Batteries will be mounted behind the seats, a single 24v Concorde, and >a backup B&C. I'm stuck on wire sizes to accommodate my goals. Wonder >if anyone would care to comment. I had planned to run #2 between the >starter contactor and the starter (both will be on the firewall). Then >#4 between the Main alternator (a 100A 24v version) the starter >contactor and the main batt contactor (which will be at the batteries >about 5ft behind the firewall). Because the standby alternator is only >20A and a backup, was going to run #8 for it thru the firewall, to the >battery contact/cross tie. Mine you, the cross tie will be "strap" >connected so it won't actually be wire there. > >But after seeing a few larger airplanes, I started to re-think this >plan. Perhaps I should use #2 for everything on the Main battery side, >and stay either with #8 or go to #6 or #4 on the standby side. > >Trying to avoid losses over length, etc. I've looked thru everything I >can find on Bob's site, but most of them are for 60A alternators on the >main side and 12v, so I'm really not sure what to do. > >Any takers? > >To help with a little more placement info. The firewall will have the >starter contactor only, the batteries are about 5-7 (wire feet) behind >the firewall, the battery and cross tie contactors will be at the >batteries. I'd run a 2AWG ground for both batteries. Put crosstie contactor on firewall to use as fwd distribution point for the two systems. Run 2AWG for all fat wires on the main battery(+) side and 4AWG for fat wires on the auxiliary battery(+) side. P.S. Use welding cable for jumpers from battery(-) terminals to common gnd and battery(+) terminals to their respective contactors. Use what ever style wire you like for other conductors. Bob . . . ---------------------------------------- ( IF one aspires to be "world class", ) ( what ever you do must be exercised ) ( EVERY day . . . ) ( R. L. Nuckolls III ) ---------------------------------------- ________________________________ Message 3 _____________________________________ Time: 07:01:06 AM PST US Subject: RE: AeroElectric-List: Wire size dilemma From: Alan, Just thought of something else. As Bob indicated (contactors on the firewall) Lancair sells a pre-built mountable package which includes the contactors, fuses etc. I assume you are using the Lyc 540? I am doing a similar thing with the Subaru engine except my two batteries will be supported by a single alternator for the electrically dependent engine. It still makes sense to keep the battery contactor near the batteries. For these glass boats we need to run a fat 02 ground from the engine back to the common ground behind the seat. Let me know what you work out for your battery boxes; I've not designed mine yet. -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Thursday, March 22, 2007 11:24 PM Subject: Re: AeroElectric-List: Wire size dilemma --> At 09:42 PM 3/22/2007 -0400, you wrote: > > >Ok, so I'm planning on a dual alt/batt 24v setup for a Lancair legacy. >Batteries will be mounted behind the seats, a single 24v Concorde, and >a backup B&C. I'm stuck on wire sizes to accommodate my goals. Wonder >if anyone would care to comment. I had planned to run #2 between the >starter contactor and the starter (both will be on the firewall). Then >#4 between the Main alternator (a 100A 24v version) the starter >contactor and the main batt contactor (which will be at the batteries >about 5ft behind the firewall). Because the standby alternator is only >20A and a backup, was going to run #8 for it thru the firewall, to the >battery contact/cross tie. Mine you, the cross tie will be "strap" >connected so it won't actually be wire there. > >But after seeing a few larger airplanes, I started to re-think this >plan. Perhaps I should use #2 for everything on the Main battery side, >and stay either with #8 or go to #6 or #4 on the standby side. > >Trying to avoid losses over length, etc. I've looked thru everything I >can find on Bob's site, but most of them are for 60A alternators on the >main side and 12v, so I'm really not sure what to do. > >Any takers? > >To help with a little more placement info. The firewall will have the >starter contactor only, the batteries are about 5-7 (wire feet) behind >the firewall, the battery and cross tie contactors will be at the >batteries. I'd run a 2AWG ground for both batteries. Put crosstie contactor on firewall to use as fwd distribution point for the two systems. Run 2AWG for all fat wires on the main battery(+) side and 4AWG for fat wires on the auxiliary battery(+) side. P.S. Use welding cable for jumpers from battery(-) terminals to common gnd and battery(+) terminals to their respective contactors. Use what ever style wire you like for other conductors. Bob . . . ---------------------------------------- ( IF one aspires to be "world class", ) ( what ever you do must be exercised ) ( EVERY day . . . ) ( R. L. Nuckolls III ) ---------------------------------------- ________________________________ Message 4 _____________________________________ Time: 09:04:57 AM PST US From: "John Burnaby" Subject: Re: AeroElectric-List: What did I do wrong? Bob, Eric & Matt, A thousand thanks to you all for my education on Zener diodes and how to get my lamps to work. Eric, you're right about my concept of Zeners...totally backward. I thought they "spilled" voltage over the nominal amount instead of absorbing the nominal amount. Now I think I understand what happened. John Do not archive ------------------------------------------------------------------------------------- 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.