---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Thu 12/25/08: 7 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:04 AM - Is this scheme valid to save weight, add flexibility and reduce noise from fat wires? (rparigor@SUFFOLK.LIB.NY.US) 2. 11:53 AM - Re: Li-Ion Batteries for aircraft (hgerhardt) 3. 01:27 PM - Re: Is this scheme valid to save weight, add flexibility and reduce noise from fat wires? (Robert L. Nuckolls, III) 4. 02:20 PM - AGM Battery Charger (Mike Creek) 5. 07:25 PM - Re: AGM Battery Charger (F. Tim Yoder) 6. 09:16 PM - Re: Is this scheme valid to save weight, add flexibility and reduce noise from fat wires? (Phil Samuelian) 7. 09:21 PM - Re: Is this scheme valid to save weight, add flexibility and reduce noise from fat wires? (rparigor@SUFFOLK.LIB.NY.US) ________________________________ Message 1 _____________________________________ Time: 06:04:25 AM PST US Subject: AeroElectric-List: Is this scheme valid to save weight, add flexibility and reduce noise from fat wires? From: rparigor@SUFFOLK.LIB.NY.US Merry Christmas and happy holidays to all. Have a mini break. I have an aft battery on my Europa XS with Rotax 914. Wires run parallel with radio antennas for ~ 5 or so feet. I have main battery switch in passenger headrest. Initial plan was to use #4 Tefzel wire with short pieces of #6 welding cable at battery attachment (for flexability) and at battery switch attachment (to more easily negotiate routing). I was going to turn butt connectors out of 101 copper with precise holes for #4 and #6 wires with a cross drilled hole slight outboard of each wire to allow me to add solder. Just a note that #6 welding cable has a slight larger OD compared to #4 Tefzel. I don't have space for the diameter of #4 copper plated aluminium wire. I was happy with above plan >>>>>>>>> until got to thinking >>>>>>>>>> Might be better off using two paralleled #8 Tefzel wires instead of one #4???? Could twist 2 sets of #8 together (each twist pos + neg) which could help out with potential noise on my paralleled run with RG400 antennas. #8 would be flexable enough to negate need for welding cable. Two paralleled wires in one respect add redundancy of connection. Two paralleled #8 wires are lighter than one #4. Cons: Need more terminations, but even with more terminations still lighter than #4 / #6 combo. Twisting pos + neg perhaps could somehow create more of a hazard of them shorting together compared to pos and neg #4 sitting side by side. There is a slight amount more resistance of two #8s compared to one #4. I don't think this will be too much of a problem with lower compression and slight less displacement of Rotax 914 compared to Rotax 912S. I also have heavy duty starter that in fact draws less amps compared to old style starter?? OK Is this scheme valid to save weight, add flexibility and reduce noise from fat wires? Anyone know of a source to obtain #8 wire with silver plating (would help out slightly with lower resistance)? Ron P. ________________________________ Message 2 _____________________________________ Time: 11:53:12 AM PST US Subject: AeroElectric-List: Re: Li-Ion Batteries for aircraft From: "hgerhardt" [/quote] The 1st thing I thought about when reading the 'pitched battery=no fire' story is, wouldn't it be fairly simple to design a G-activated disconnect mounted directly to the battery? Charlie[/quote] Delphi has already done this... it's a pyrotechnically activated battery cutoff switch. See http://delphi.com/manufacturers/auto/ee/eec/bdsd/ In the cars they're installed in, the airbag module triggers it. However, since we don't typically have airbag triggers on board, we could use the standard Ford fuel pump cutoff switch that Ford's been using since the mid-80's (it's a g-activated switch). Heinrich Gerhardt RV-6, flying Read this topic online here: http://forums.matronics.com/viewtopic.php?p=221100#221100 ________________________________ Message 3 _____________________________________ Time: 01:27:19 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Is this scheme valid to save weight, add flexibility and reduce noise from fat wires? At 07:56 AM 12/25/2008, you wrote: > >Merry Christmas and happy holidays to all. > >Have a mini break. > >I have an aft battery on my Europa XS with Rotax 914. Wires run parallel >with radio antennas for ~ 5 or so feet. I have main battery switch in >passenger headrest. > >Initial plan was to use #4 Tefzel wire with short pieces of #6 welding >cable at battery attachment (for flexability) and at battery switch >attachment (to more easily negotiate routing). I was going to turn butt >connectors out of 101 copper with precise holes for #4 and #6 wires with a >cross drilled hole slight outboard of each wire to allow me to add solder. >Just a note that #6 welding cable has a slight larger OD compared to #4 >Tefzel. I don't have space for the diameter of #4 copper plated aluminium >wire. That would work but is pretty labor intensive. Lapped, soldered and heat-shrink would work too and is quick. >I was happy with above plan >>>>>>>>> until got to thinking >>>>>>>>>> > >Might be better off using two paralleled #8 Tefzel wires instead of one >#4???? > >Could twist 2 sets of #8 together (each twist pos + neg) which could help >out with potential noise on my paralleled run with RG400 antennas. > >#8 would be flexable enough to negate need for welding cable. "better off", "flexible enough", "potential noise" are all non-quantified . . . and don't offer a lucid image of your design goals. >Two paralleled wires in one respect add redundancy of connection. > >Two paralleled #8 wires are lighter than one #4. But smaller in cross-section than one #4. >Cons: > >Need more terminations, but even with more terminations still lighter than >#4 / #6 combo. > >Twisting pos + neg perhaps could somehow create more of a hazard of them >shorting together compared to pos and neg #4 sitting side by side. > >There is a slight amount more resistance of two #8s compared to one #4. I >don't think this will be too much of a problem with lower compression and >slight less displacement of Rotax 914 compared to Rotax 912S. I also have >heavy duty starter that in fact draws less amps compared to old style >starter?? Exactly how much weight are you "saving" and how much $time$ are you investing in the goal. You've added joints to the system that wouldn't have to be there with a contiguous run of 4awg welding cable. Have you calculated the delta-weight for the proposed architectures? >OK >Is this scheme valid to save weight, add flexibility and reduce noise from >fat wires? Don't worry about noise from these wires into antenna systems or feedlines. Twising is not necessary either. Just run them tightly parallel with string ties every 6" or so. >Anyone know of a source to obtain #8 wire with silver plating (would help >out slightly with lower resistance)? Silver plated wire comes on Teflon insulated conductors. More expensive, less robust and so small an improvement as to not be noticed. I'd still like to see how much weight you expect to save with any alternatives to single strands of 4AWG. How long are these runs of wire? Bob . . . ________________________________ Message 4 _____________________________________ Time: 02:20:40 PM PST US From: "Mike Creek" Subject: AeroElectric-List: AGM Battery Charger Is a special charger needed for AGM batteries such as the Odyssey? At www.odyessy.com they recommend two types, but I'm wondering why something like a Schumacher http://store.schumachermart.com/se-1010-2.html won't work just as well. ________________________________ Message 5 _____________________________________ Time: 07:25:31 PM PST US From: "F. Tim Yoder" Subject: Re: AeroElectric-List: AGM Battery Charger odysseybatteries.com ----- Original Message ----- From: Mike Creek To: aeroelectric-list@matronics.com Sent: Thursday, December 25, 2008 3:16 PM Subject: AeroElectric-List: AGM Battery Charger Is a special charger needed for AGM batteries such as the Odyssey? At www.odyessy.com they recommend two types, but I'm wondering why something like a Schumacher http://store.schumachermart.com/se-1010-2.html won't work just as well. ________________________________ Message 6 _____________________________________ Time: 09:16:19 PM PST US From: Phil Samuelian Subject: Re: AeroElectric-List: Is this scheme valid to save weight, add flexibility and reduce noise from fat wires? Ron: If you need the capacity of #4 wire for the starter, 2 #8 wires have much less capacity than 1 #4. Two #7 wires are very close to the same capacity, but I'm not sure of #7AWG availability. I would recommend staying with the first plan, using #4 cable. Radio interference would be from the alternator charging, but it's at a much lower ampere rating and would produce much less EMI than when starting the engine. Also, invest in the highest quality cable for the antenna. If interference even exists after that, then use filters to clean that up. Phil On Dec 25, 2008, at 5:56 AM, rparigor@SUFFOLK.LIB.NY.US wrote: > > Merry Christmas and happy holidays to all. > > Have a mini break. > > I have an aft battery on my Europa XS with Rotax 914. Wires run > parallel > with radio antennas for ~ 5 or so feet. I have main battery switch in > passenger headrest. > > Initial plan was to use #4 Tefzel wire with short pieces of #6 welding > cable at battery attachment (for flexability) and at battery switch > attachment (to more easily negotiate routing). I was going to turn > butt > connectors out of 101 copper with precise holes for #4 and #6 wires > with a > cross drilled hole slight outboard of each wire to allow me to add > solder. > Just a note that #6 welding cable has a slight larger OD compared > to #4 > Tefzel. I don't have space for the diameter of #4 copper plated > aluminium > wire. > > I was happy with above plan >>>>>>>>> until got to thinking >>>>>>>>>> > > Might be better off using two paralleled #8 Tefzel wires instead of > one > #4???? > > Could twist 2 sets of #8 together (each twist pos + neg) which > could help > out with potential noise on my paralleled run with RG400 antennas. > > #8 would be flexable enough to negate need for welding cable. > > Two paralleled wires in one respect add redundancy of connection. > > Two paralleled #8 wires are lighter than one #4. > > > Cons: > > Need more terminations, but even with more terminations still > lighter than > #4 / #6 combo. > > Twisting pos + neg perhaps could somehow create more of a hazard of > them > shorting together compared to pos and neg #4 sitting side by side. > > There is a slight amount more resistance of two #8s compared to one > #4. I > don't think this will be too much of a problem with lower > compression and > slight less displacement of Rotax 914 compared to Rotax 912S. I > also have > heavy duty starter that in fact draws less amps compared to old style > starter?? > > OK > Is this scheme valid to save weight, add flexibility and reduce > noise from > fat wires? > > Anyone know of a source to obtain #8 wire with silver plating > (would help > out slightly with lower resistance)? > > Ron P. > > ________________________________ Message 7 _____________________________________ Time: 09:21:13 PM PST US Subject: Re: AeroElectric-List: Is this scheme valid to save weight, add flexibility and reduce noise from fat wires? From: rparigor@SUFFOLK.LIB.NY.US Hi Bob Thx. for the reply My mission is to electrically connect my aft battery to the upfront 914 supplying it sufficient amperage and voltage, while being able to fit wires neatly under door sill/fuse seam and allow routing required to connect to battery switch (tight bends). Old style starter amp draw is stated at I think 60 amps, I have new style that is a bit less. If I can save some weight in the process that is a bonus. Just a quick calculation of one #4 compared to two #8s for 5 meters of wire would be a savings of a little over a half pound with two #8s. The larger the diameter of wires, the harder it will be to route under door sill and allow for door centering pin receptacle to help keep door from bulging. #4 Tefzel wire is .310" in diameter #6 EPDM jacket 259 strand is .332" diameter (#4 406 strand .380") #6 Chlorinated Polyethylene 660 strand is .370" diameter (#4 1045 strand .420") It's true I could lap solder #6 welding wire to #4 Tefzel, but my interior cover/conduit for wires would need to be larger to accommodate, and the laps would be in an already tight area. Butt soldering #4 Tefzel to #6 welding would approx. be the same diameter. I am not sure of the weight of welding cable compared to Tefzel, but I would think it heavier. I have a Hobart TRT 250 TIG welder. The ground wire I suspect is EPDM jacketed. It has cracks and splits and in general the jacketing is in bad health. True it sees a lot of UV and for a TIG ground strap that is fine. Are you be happy with using EPDM jacketed welding cable for the full run to and from engine to aft battery knowing if it smokes, a dozen feet is in the cockpit (aeroplane is fiberglass)? How about only 1 foot? Same question with Chlorinated Polyethylene jacketed welding cable: Are you be happy with using Chlorinated Polyethylene jacketed welding cable for the full run to and from engine to aft battery knowing if it smokes, a dozen feet is in the cockpit (aeroplane is fiberglass)? How about only 1 foot? Knowing I need flexibility for routing at battery switch, want the smallest diameter that is feasible, be able to provide reasonable voltage and cranking amps, not take unreasonable risks of breathing noxious fumes if wires smoke, not have much risk that aging wire insulation will crack and split and be the instigator of smoke and loss of electron flow and be of a reasonable weight. What would be your two favorite choices: ****#4 Tefzel with #6 EPDM jacketed butt soldered battery and battery switch ends? ****#4 Tefzel with #6 Chlorinated Polyethylene jacketed butt soldered battery and battery switch ends? ****All #4 EPDM jacketed wire? ****All #4 Chlorinated Polyethylene jacketed wire? ****Two paralleled #8 Tefzel wire that doesn't need twisting? Thx. Ron Parigoris ------------------------------------------------------------------------------------- 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.