Quote:
Originally Posted by Ryland
I checked some online wire size calculators and figured that for around 6 feet of cable at a peek of 400 amps but a sustained 150-200 amps that 4 gauge cable would be fine, auto parts stores should have bulk red and black cable, I really like welding cable because it's finer strands of wire so it's softer and more flexible,
If you are going to draw more then a peek of 400 amps or have a longer run then 6 feet or so total of battery cable then go with a larger size cable, on a motorcycle tho you can keep everything close.
|
Chicken wire (small cable) can be irritating though because its easier to break (and wear out) My c-car is a rats nest of white 18 gauge, very irritating, a variety of "components" are no longer functional and I have no idea why they are wired, but alas his is a new one not a 3 previous owner kludged special.
Also, although I recommend the biggest gauge (numerically smallest) you can handle in any EV conversion, if he has the wire or its real cheap I would estimate that he could get away with very light gauge wires 6 or 8 gauge.
DC applications are not like AC in that you have a time variable in there and voltage drop is "less" important.
So even if he peaks over 400amps, on a motorcycle the duration would be minimal and likely his run time is also minimal, so he could get away with light stuff just because he would be within the 1hr rating for the material averaged out.
This saves a tiny bit of weight and potentially a a fair amount of cost, but he would loose a few percentage points on his efficiency mainly at high loads. He also might loose durability if the cable is not properly rated for vehicle use and rubs which to me is more important than the gauge, one reason why I have 0/3 welding wire even though I probably only need 4 gauge in here too.
I would say though that he better make sure battery interconnects are ALWAYS top notch, its the longer runs to the controller and motor that can be cheaped out on.
Kind of like the 80's GM vehicles with a 60amp alternator and 12 gauge wires.