Positive cable overheating on eg-4 bus bar

[iwasforcedtopickausername]

Seems like a 1 AWG wire and brass does not seem ideal. That said, for another take, could you wire some solar panels directly to your water heater, bypassing the rest of the system?

Would be good to look at it with a thermal camera, too.

 

[Mannfamilywoodworks]

Seems like a 1 AWG wire and brass does not seem ideal. That said, for another take, could you wire some solar panels directly to your water heater, bypassing the rest of the system?

Would be good to look at it with a thermal camera, too.

Water heater is most likely ac and panels produce dc…how would you bypass the device that switches dc to ac?

 

[JoeHam]

Water heater is most likely ac and panels produce dc…how would you bypass the device that switches dc to ac?

It’s just a resistor. Doesn’t care about AC or DC.

The thermostat may be a problem. Also Need to compensate for voltage but that’s a simple math thang.

First google thing I found :

120 AC?DC water heater element

I have tried several DC hot water elements and so far none work as well as my test bench 120AC heater.

forum.solar-electric.com

 

[Bruxollini]

Iirc I've seen posts here saying you want one of the cables to be on bottom of the bus bar the other on the top, I could be wrong.
Is each battery pack at the same voltage / capacity or do you see the top behave differently than the rest?

Yes, I’m working on rearranging all the cables and connections and making them a little neater, and then flipping the negative bus bar over so that the positive connection is in top, and negative at the bottom, thus hopefully eliminating any current sharing problem. Right now the priority is to replace the cables with 4/0 wag ones.

 

[Bruxollini]

I would change the brass bus bar to somethign that is rated for the max amperage of your system, that is copper, made by a reputable dealer, or do calculations to figure the correct thickness and make it yourself. 3/4" X 1/4" is good for around 200 amps and your 4.5 kw at 48 volts (I have no idea your voltage) pulls around 100 amps. It can't just be for the water heater but all the loads you can expect to have on at a time.

This chart tells me the thickness of the wire based off ampacity. Manufacturer spec sheet is more accurate.:

View attachment 118500
Is it possible there was another high amperage item turned on? My guests and family are not much on limits. Including letting me sleep while low voltage alarms are going off.

Turns out the water pump was running along with the water heater.
, probably pulling around 200 amps altogether, and my 5 battery bank is capable of 175, 35amps per battery. There in lies the problem.

 

[Supervstech]

Turns out the water pump was running along with the water heater.
, probably pulling around 200 amps altogether, and my 5 battery bank is capable of 175, 35amps per battery. There in lies the problem.

That is a contributor for sure, but the inverter NEEDS 2/0 minimum feeding it.

 

[Bruxollini]

It now has 4/0

 

[42OhmsPA]

It now has 4/0

Now you can look into getting a thermal camera and run the same scenario again. ??