6 volt t105's in series/parallel

[handcrafted]

I currently have my 675amh battery bank on 4awg wire with the charger supplied by it's factory 6awg I charge from 15 amp to 50 amp monitoring closely, my question is this. I am up grading to a prowatt 2000 inverter pure sine and it specs for a 4/0 wire for supply, I'm thinking I should not only up battery bank to 2/0 too 4/0 copper wire but I should also go in and up my chargers supply wire to at least 1/0 or even 2/0 I have noticed that if my battery bank is below 12.89v the 6awg supply wires get warm and the circuit goes to cycle 3mins on 1min off and anything above 12.89 my charger will charge at 50amp with no problem and nothing warms up but the batteries. All thoughts welcome thank you

 

[BradtheRad]

It will benefit if you install larger wires, of course.

See the wire ampacity tables, below.

One reason for wires to heat up, is if there is a dirty connector somewhere. This creates resistance, which causes a voltage drop, which results in wasted power. Example, at 50 Amps, just .01 ohm will result in 25W of heat waste (50 * 50 * .01).

Your charger sends higher charge current to depleted batteries (when below 12.89 V). You say it cycles on and off.
Question: Does the charger heat up internally, to cause it to do this?
Or does it sense something in the battery bank, through the wiring?

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Links to charts of wire gauges showing safe amp-carrying capacity:

http://amasci.com/tesla/wire1.html



http://www.powerstream.com/Wire_Size.htm

Here's a link to another wire gauge table. Its ampacity values are much different than the other tables.

**broken link removed**

Possible reason for the disparity: One source may base ampacity on a higher temperature which makes the wire get too hot to hold, while the other source may use a lower temperature where copper's electrical characteristics start to change even though it is only warm.


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[handcrafted]

wow bradtherad time flys I've been away from here for few weeks and thank you for your question my charger is a Sears diehard commercial charger and it does have a sensor that if heated up will cause the charger to charge for 3 mins. then rest for 1 min. or maybe the reverse either way I've been thinking of one of two things and or both, open up the charger and step up the output leads to larger gauge wire, and since I monitor my charging and never leave home while charging maybe eliminate the cycle controller all together so that I can get a continuous 50a charge at any level, although I feel I may have to add in an additional fan to keep the transformer cool cause that's the only reason it cycles is the transformer gets to warm I just don't understand why it only does it when the batteries are below 12.89v oh and to answer your question on the back of the charger inside there is a switch if you will that the positive output lead goes through and then out to the batteries and it makes a noticeable click when it cuts out and back in this is the item I am thinking of over riding. Thanks again ciao

 

[BradtheRad]

I just don't understand why it only does it when the batteries are below 12.89v

That's when the most Amperes are drawn from the charger. That heats it up.

on the back of the charger inside there is a switch if you will that the positive output lead goes through and then out to the batteries and it makes a noticeable click when it cuts out and back in this is the item I am thinking of over riding. Thanks again ciao

Sounds like a thermal-activated circuit breaker. If you override it, you're asking for problems with overheating. Then you can expect shortened life for the transformer.