Solar Panel Problem

Page may contain affiliate links. Please see terms for details.

ren531

Über Member
Location
Lancaster uk
Can anyone give me some advice about a solar panel installation on our roof, we have had it for 5 years but has now stopped working, the inverter says low Riso and no green light on just the GFI red light lit up, Google says this is a fault with low resistance on the dc side posibly with the wiring or connectors on the roof. My knowledge of electrics is zero, can anyone advise me on this.
 

cheys03

Veteran
Low resistance suggests a short, possibly? So the first step is to trace the cables and connectors from the inverter to the panels looking for signs of physical damage (rubs, cuts in the cable insulation etc) and heat damage (bubbling, melting etc from any short circuit). After that look at the connectors too as suggested by your Google search. If no evidence of problems from visual inspection you’d need a multimeter or similar to continue diagnostics, if you have one. Otherwise might more prudent to call an electrician with solar experience.
 

Drago

Legendary Member
What make of inverter? Although the fault code reads as an external problem, on some makes that's indicative that the inverter itself has gone south. 5-7 years is the typical lifespan of a typical inverter. Some sources claim more, but I'm doubtful.
 

Yellow Fang

Legendary Member
Location
Reading
Can anyone give me some advice about a solar panel installation on our roof, we have had it for 5 years but has now stopped working, the inverter says low Riso and no green light on just the GFI red light lit up, Google says this is a fault with low resistance on the dc side posibly with the wiring or connectors on the roof. My knowledge of electrics is zero, can anyone advise me on this.

Not low resistance but low insulation resistance. That might mean a bit of a cable's plastic insulation has worn away, or somehow come away from the wire. If you get some moisture, e.g. rain, it might short to ground. You'll probably be alright.

According to the ABB / Power One Aurora operators manual Riso Low indicates the inverter has detected low insulation resistance on the DC side of your solar power system; this is usually not an issue with the inverter but with the DC circuit connected to the inverter
 

Drago

Legendary Member
They say that, but when my inverter showed the same fault it was actually an internal fault with the inverter itself, albeit mine wasn't an ABB. I think the only way to be sure is for a properly equipped engineer to take a peek.
 
OP
OP
ren531

ren531

Über Member
Location
Lancaster uk
I have found someone to help we fixing the issues with the panels and he agrees with others that it will be an issue with the dc wiring side.
 
Top Bottom