Installing a new converter and need advice on cable size

darsben wrote:
Why?
You have a 90 amp converter but your DRAW from the battery(ies) remains the same so no upgrade is needed.
Your charge rate should not approach the capabilities of the cable. Clean the connections and make sure all connections are tight.

THIS.

Assuming that the "charging line" will be protected with a 45 amp fuse unless you change it, I vote for trying it out first.

I think that it is HIGHLY unlikely that you well ever approach 90 amps unless your batteries are stone cold dead and maybe not even then.

Routing heavy gauge cable is sometimes REALLY difficult.

X2 on the 4 gauge

You will also have to up the fuse/circuit breaker rating that is installed close to the batteries between the batteries and converter/charger. If you have a 45AMP rating remaining here it will blow the fuse or trip the breaker when the battery demand gets higher than 45AMPS...

My inline fuse protection was 30AMPs original with my small converter/charger and it is 80AMPS with my PD9260C setup. Probably a tad too high but that is what I found in the goody box here... My original #8 cable was upgraded to 4AWG to use with the PD9260C unit...

ADDED Note: When camping off the power grid I usually pull aroound 20AMPS DC to run things and when I am using my PD9260C running off of a generator to charge up my 255AH battery bank I see around 52-53 DC AMPS being demanded by my battery for 15 minutes or so when first starting up my BOOST charge mode.

Roy Ken

westend wrote:
The price of 4 ga welding wire is not that much more than the 6 ga you should have to handle the current of the charger. 4 ga will have less voltage drop than 6 ga. You will have the advantage of the larger cable for the life of the converter. The last time I bought 4 ga it was about $1/ft.

Nobody on this Forum, including the OP will know the draw of the batteries and the possible current from the converter to the batteries. It is a dynamic number and could approach 90 amps. That is why the proper sized wire is stipulated to handle the power.

Eggzactly.. The charger will supply what the battery demands

The price of 4 ga welding wire is not that much more than the 6 ga you should have to handle the current of the charger. 4 ga will have less voltage drop than 6 ga. You will have the advantage of the larger cable for the life of the converter. The last time I bought 4 ga it was about $1/ft.

Nobody on this Forum, including the OP will know the draw of the batteries and the possible current from the converter to the batteries. It is a dynamic number and could approach 90 amps. That is why the proper sized wire is stipulated to handle the power.

Why?
You have a 90 amp converter but your DRAW from the battery(ies) remains the same so no upgrade is needed.
Your charge rate should not approach the capabilities of the cable. Clean the connections and make sure all connections are tight.

Or upgrade the cables while you're at it and do it right

Maybe you can set the current limit to 45 and use your existing cables.
Call the company and ask them.