Solar panel question

[CompairHolman]

I have 4x 125w panels wired series / parallel and one has been smashed, I'm very busy right now so can I just leave it like it is or should I disconnect the broken panel asap ?

 

3 panels will be under the max voltage of my charger so I will rewire them in series at some point.

[Jackofalltrades]

Someone will no doubt correct me if I'm wrong but my concern would be if any of the diodes are damaged in the smashed panel, possibly leading to a short and the other panel(s) continually sending power to it until something melts. I might be over-thinking this though.

 

Are the panels fitted with MC4 connectors? It should be quick & easy to disconnect the damaged series pair and the damaged panel from the good one, surely?

 

Out of interest how did the panel get smashed - accident or deliberate/malicious?

 

[CompairHolman]

No connectors but the cables are easy to access.

 

My feeling is a fisherman cast a weight on it, I heard this happen a few days ago but I never saw the panel was smashed last the time.  

[Jen-in-Wellies]

4 panels wired series/parallel. If one has been completely smashed, then the other wired series with it will also not be connected. The other two will likely be unaffected, so you have two panels still. Even the broken panel may still be doing something, depending on how it is wired internally. There are series/parallel connections within the panel. The exact way will depend on the panel, but if there is still an intact series string between the red and black wires heading out, then it will still be producing something. The reduced capacity of this panel would likely drag the other one wired in series down to the same level, but again, the other pair of series wired panels would be unaffected.

Before the panel is replaced, like with like, you can wire the remaining three in series, or parallel. If in series, make sure the max input voltage of your solar charge controller won't be exceeded. Use panel open circuit voltages for a safety margin. In parallel, make sure it won't exceed the max current for the charge controller. Not so much of a problem this time of year, with the sun still low in the sky.

Jen