Off grid house - Does anyone know how to find short circuits affordably? (contractors, live)

[hapci534]

I have an off-grid house, 6 batteries of 1350 Amp hours total feeding and inverter and then a grounded electrical box that supplies a conventionally wired house. Everything works fine… until a big rain comes. When rain hits, battery charge goes down from 80% to 0% in about 15 minutes. I see no arcing anywhere, no bursts of noise (though I don't visit the attic much) but the water is clearly causing some sort of slow discharge somewhere. Is there a way to track the issue down without spending half a grand?

During the recent big rain, I experimented by turning all the circuit breakers off, energizing lines one by one with no appliance running and watching the battery charge percentage change. Some lines lost 0% of charge. The longest line feeding my cable modem’s wall plug in the farthest corner lost 13% battery charge in 5 minutes. Cowabunga! But next day a 0% line also drained the battery. WTH, the short circuit moves around? Do circuit breakers / electric boxes go bad after several decades? I could really use some advice. Thank you

[Strannik33]

How about asking an electrician?

[Futuremauian]

Electrical and plumbing are the two areas where a homeowner/builder are required to use licensed contractors. If you just needed to change a light switch or a receptacle, I would encourage you to do it yourself.

A phantom electrical discharge is difficult to diagnose and potentially dangerous if you don't have the right skill set. Do yourself a favor and call an electrician. Preferably after checking around for one who has this specific knowledge.

[terracore]

I'm not an electrician, but based on your description and my dangerously low lack of knowledge, it sounds like it's a DC problem (before the inverter).

Your post didn't talk about the solar panels or wiring. Are any of the wires in the gutters?

[hotzcatz]

Well, it sounds like some sort of something is grounding somewhere, but since it's going through 1,350 amp hours and nothing is welded to anything else it sounds like the safety systems somewhere may be working. BUT! This is something that could kill you, if you don't know enough that you're asking an online forum, I doubt we would have enough of an answer that you'd want to bet your life on it. Literally, I might add.


When I lived on my boat, there was another boat out in the harbor that ran a big generator for power. He was looking for a short in the generator while standing in bilge water and using a metal screwdriver to poke at it. Needless to say, he found the short. Why his wife didn't shut off the generator before rowing to shore to find help I don't know, but the end result wasn't good. His widow sold the boat soon after and the new owners took out the generator. Not the fix he was looking for and one you shouldn't copy!

[whtviper1]

Originally Posted by hapci534

Is there a way to track the issue down without spending half a grand?

It would be a "half a grand" well spent if that is all it took to fix the issue.

[Hawaii_Bound]

yes there is. You need a multimeter to diagnose which battery is bad. You will need to unhook all the battery leads to tell which one is bad. How many volts is your system?

[hapci534]

My system is 12V., Hawaii_Bound.

[Hawaii_Bound]

Ok I would take your battery bank apart and measure the voltage of each battery. They should be sitting at like 13 volts fully charged. Sounds like you have some bad cells in at least one battery.

[Futuremauian]

Originally Posted by Hawaii_Bound

Ok I would take your battery bank apart and measure the voltage of each battery. They should be sitting at like 13 volts fully charged. Sounds like you have some bad cells in at least one battery.

Bad cells would be triggered to discharge only after a heavy rain?