GFI fault showing on Power One Inverter

[Ian-LS]

You paid for a two year warranty extension? with the installer?

They are supposed to give you at least a 2 year warranty to start with and shouldn't charge you for an extended warranty to take it from one year to two years. This is detailed with the REAL scheme I believe.

 

[silverpulser]

Solar electrician has now been and gone. As expected there was nothing to find after all the recent sunny weather. He did note that the connectors weren't MC4 but rather Phoenix connectors and they were located inside the roof space. Not sure what that all means but in any event he has asked me to call him if/when there is any change in the Riso measurement.

Shaun

 

[silverpulser]

Solar electrician has now been and gone. As expected there was nothing to find after all the recent sunny weather. He did note that the connectors weren't MC4 but rather Phoenix connectors and they were located inside the roof space. Not sure what that all means but in any event he has asked me to call him if/when there is any change in the Riso measurement.

Shaun

Update:

Scaffolding erected and electrician inspected the suspect string. One connector was wet and changed. Remainder tested OK.

For the week following the RISO has measured between a low of 8.1 Mohms and high of 15.8 Mhms at startup. On each occasion it returned to 20 Mohms when restarted later in the morning.

Electrician rang Power-One who say this is normal where there is morning dew.

What do you guys think?

 

[Gavin A]

the limit is usually 1 Mohms for BS7671 (wiring regs), so it's a bit low, but passes. It's normal to have a lower RISO figure when there is dew or in wet weather due to reduced resistance / increased capacitance from the panels (IIRC).

 

[edexlab]

Heard of this problem with the connectors but have yet to see it for myself, most PV connectors are IP 67 so a bit of morning dew or even heavy rain shouldn't be a problem surely?
unless the ends haven't been tightened up properly, the tools for this are rubbish!