P.V panels tripping house DC circuit breaker

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Alan B

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Aug 3, 2023
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Location
Ashburton Devon
I have some panels that would be around 15 years old ,when it rains they trip the AC 30 ma house circuit breaker [63amps].

after the isolator is turned off i can reset and all is well .

where and how would i begin to test ,they are set up as two strings of 7 panels .

I replaced a few that had visable corrosion at bottom end of panels .

they are 175 watts a piece at around 6amps ,the backing paper has changed from white to light brown .

I have a basic multimeter but am a novice . regards Alan
 
Sounds more like a possible fault with the inverter. Nothing from the panels should get to the AC side. Your solar shouldn't be sharing a RCD with any other circuit either. It's also possible it's nothing to do with the solar, and a.n.other appliance is faulty.
 
You need an electrician to look over the problem also solar systems should be protected by their own rcd protective circuit breaker either rcbo or rcd/mcb setup so having solar runnig your house rcd isnt really correct tbh
 
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You need an electrician to look over the problem also solar sustens should be pritected by their own rcd protective circuit breaker either rcbo or rcd/mcb setup so having solar runnig your house rcd isnt really correct tbh
If it's 15 years old, that was pre working out sharing RCDs is a bad idea. The sharing of RCDs being potentially dangerous is a claim to fame of the members of this forum in a long discussion many years ago.
 
If it's 15 years old, that was pre working out sharing RCDs is a bad idea. The sharing of RCDs being potentially dangerous is a claim to fame of the members of this forum in a long discussion many years ago.


Problem is new installs of PV are still being done this way
 
If it's 15 years old, that was pre working out sharing RCDs is a bad idea. The sharing of RCDs being potentially dangerous is a claim to fame of the members of this forum in a long discussion many years ago.
But i didint mention about it being dangerous though i said it was not really correct
 
okay ,could you suggest what milliamps the new trip should be ? would a rcd/mcb or rcbo [as badger suggested] be better for D.C solar .
I will get a sparky to install for me . Thanks folks Alan
 
Hi murdock, please see attatched photos. this was a recent installation with new CU. But RCD by meter is quite old .
I have also included diagrams from the manufacturer of the Epever invertor. who recommend no RCD .
when the p.v panels are isolated everything runs fine ,but problems started when we had rain.and rcd trips .
I have two strings of 7 panels @24 volt each .i wonder if i could narrow the problem down by isolating one string at a time
although this would only give me 168 volts [min working p.v voltage is 120volt. kind regards Alan20231027_101040.jpg20231027_101106.jpg20231027_101116.jpgScreenshot (23).pngScreenshot (24).png
 
I would get that fully investigated / update all the boards.

At 15 years old, there's a chance the inverter is just at end of life. A new unit will be more efficient than what you currently have anyway, and pay for itself in a few years. Out of interest, if you turn off the other circuits when tripping happens, does it keep working?

Generally speaking, a fault with the DC side should show as a fault code in the inverter screen, usually 'riso' which would indicate earth leakage around the panels. I'm not familiar with your unit, so you may not have a screen at all, but there's usually some form of visual fault indication.
 
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