[DIYguy]

Originally Posted by F16bmathis

You know, I never actually measured the distance of all the 2/0 cables, but I'm going with closer to a little over 20 feet. My intent is to install 4/0 when it gets warmer. Evey little bit helps.

I read your "story" on your evalbum.. All I can say is OMG!! lol lol

[ElectriCar]

I read it too and laughed a lot! Can you imagine? And all the money, Poof!

[F16bmathis]

Originally Posted by ElectriCar

I took my truck on a speed run and hit 85 with it, later to find out with a bad connection. I saw you hit 78 or so. Could your wires have been part of why you couldn't go faster? Wasting 5-6 volts is a lot of wasted juice!

During the run I ...you likely would have been faster!

I run ...reason to push my budget a little.

If you are ...one wire.

I actually didn't try to go faster, but I'm sure I was at the end. I'd like to see how fast I'm able to go with the 2/0 then switch to 4/0 and see the improvement.

[ElectriCar]

There you go. Do a run at 100%, recharge then switch your cables and try it again.

[JRP3]

How warm are the wires getting? If they aren't that warm there may not be much difference.

[DIYguy]

yes, it may not be a case of "how fast" you can go...more like "how fast for how long".... The short interconnects are likely fine at 2/0. The longer runs from one box to another... or from back to front could go to 4/0 if you have the rest of the "parts" to warrant it. Also, motor to controller should be 4/0 in my opinion.

[ElectriCar]

IF his leads are indeed total 20', from Controller + through all batteries to Controller -, then 1000A is not going to drop but 1.6V, just over 1% of a 144V pack.

Here's why I brought this up. I'm a contractor and never knew how to calculate losses in wiring based on it's size and load, even when I did industrial wiring. I had to learn that to get my license, its' part of designing circuits in buildings.

Buildings may have long runs of wiring with low currents, ie 500' building with a row of lights drawing 13A. But the 13A must travel 500' to the fixture and 500' back, a 1000' loop! Since wire IS a load, just like a motor it uses power, just like a motor.

Where motors draw high current in a short wire, a building uses a low current but on a long run it's a high resistance load and will have the same effect if not sized for the length and current expected.

Perfect example. In my home, wired by an idiot, I had a heater plugged in rated 1500 watts and noticed it wasn't producing heat nearly as good as at my other house. Upon checking the voltage at the plug, it would drop to 110V when turned on. The voltage at the panel was 120V.

After crunching some numbers, a 8.3% loss of voltage cost me a 29.6% reduction in power to 1056 Watts. The original wiring loop appeared about 250' total of #14 wire, a loop of 500'. I then had my guys replace the wiring to a few receptacles with new circuits to the panel with #12 and shortened the loop quite a bit. With the heater running on the new wire, the voltage only dropped to 119V.

That's why you need to size your pack right IF you're want to get the performance of your pack it can deliver. Otherwise you're wasting power warming your wiring.