why overkill cabels?

Joel Craig

I have been seeing many post on here mentioning the installing of 2gage cables. Can anyone explain to me why so big?

BGW

__________________
This advertising will not be shown in this way to registered members.
Register your free account today and become a member on Buggies Gone Wild Golf Cart Forum

teecro

Well its not exactly overkill going to 2 gauge cables when you consider that 6 gauge which is generally stock is only good for 250 amps. 4 gauge cables are good for 500 amp and its only a couple of bucks more to go ahead and install 2 gauge and know that your cabling will NOT be the cause of a limitation in speed or torque on your newly hopped up cart. Why would you install a 500 or 700 amp controller and leave the 250 amp wires? This makes even more sense on 36 volt carts that are looking for an increase in power as the lower voltage causes and even higher demand as well as need for increased amps...

Consider it like putting out a fire with a 5/8" garden hose while you just might be able to do just that it will be so much easier to do it with a 1.5" fire hose...

BobBoyce

It lowers I*R losses. Basically, larger cables allow for more current to flow with less voltage drop in the cables. The general rule of thumb is... Current makes torque while voltage helps to make speed.

It's more complex than that in actual practice, and there are many other variables that can come into play, but that's the basic idea.

Bob

Lochlin

You ask why. I ask why not. It is, literally, a few bucks extra to go from 4 gauge to 2 gauge. And when I say a few, I mean a few. I upgraded a cart last year and I believe the difference in cost was less then $20.

Indeed, one's setup may be just fine with 4 gauge. Still, for a few bucks more why not do it? If nothing else you will be prepared for any future upgrades that might come down the pike without having to do another wiring upgrade.

cgtech

milliohms matter. any heat lost in cables is energy that is not being put to use moving you down the road.

JohnnieB

Overkill is underrated.

The purpose of the high current cables is to transfer electrical power (Watts) from the battery to the motor where most of the Watts from the battery are converted to Torque and some are wasted as Heat.

Unfortunately, the only the high current cables we have available to us have resistance and some of the Watts from the battery are converted to Heat (W = I²R) and wasted before they reach the motor.

At 500A, 25' of 6Ga cable wastes about 2469W (3.3HP), 25' of 4Ga wastes about 1553W (2.1HP) and 25' of 2Ga cables wastes about 977W (1.3HP).

The wattage losses are proportional at all amp flows, so the thicker the high current cables are, the greater low end torque and top speed will be in the same cart with no changes other than cable thickness.

In a nutshell: Regardless of battery pack voltage and controller ampacity, a electric golf cart with thicker cables will have better overall performance than the same cart with thinner cables.

Joel Craig

Crap! You guys are great! I feel smarter than ever now. Thank you all very much.