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Old 03-25-2006 | 11:54 AM
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Tom Antlfinger's Avatar
Tom Antlfinger
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From: Fond du Lac, WI
Default RE: Opto-isolator or not

Good points Mark......I still see folks installing a PowerBox with dual 4000 Liths and then using 22 ga, 48 inch wires downstream to the servos......Also note that Duralite Plus 4000maH RX packs are still shipped with a single 22ga output wire, same dimension as the charging wire which carries no more than 2 amps while charging....should have at least 18 gauge, and preferably 16 ga with something like a Deans Ultra Plug going into the switch and regulator.....preferably using a Perfect Switch setup so all that current doesn't go thru the mechanical switch, most of which develop significant voltage drop after 5 amps is pulled through them, even the HD models

I don't have the exact current limits for point to point wiring with standed copper wire at hand, but for solid conductor 18 ga it is 16 amps, vs 22 gauge is only 7 amps, reflecting a greater than double the resistance in 18 vs. 22 gauge......I agree that manufacturers should be phasing out 22 ga wires for digital servos in favor of 18ga which is a big as I have been able to get into standard JR or Futaba connectors.....and then going to 16 ga from BAT to switch, and then dual 18 ga out of the switch to the RX......would be nice if all RX had 2 separate BAT inputs to the bus......


Your BAT comments are right on.....I have done my voltage drop test as described in one of my prior posts on this thread, using a 1400maH AA Nicad pack, and 1800maH sub-C pack, as well as my newest 3500 maH pack......the results are drastically different, with major voltage drops of over 1.5v with a 4 amp load on the smallest pack right off the charger, with essentially no voltage drop on the 3500 pack until it is discharged to about 50% of it's rated capacity......


Tom