Solar New Solis inverter trips house electrics

[iainco]

Hello there

I have just installed a new Solis S6-GR1P3.6K-M-DC Inverter - this replaced a 10 year old+ Sungrow inverter that failed/out of warranty!

None of the wiring set up has changed other than a new AC plug for the Solis inverter. I have a 16-panel 4kw system.

It seems, when the inverter 'wakes' in the morning it trips the main house electrics RCD/consumer unit. The solar system is running through a 20amp RCD on the consumer unit and as I say, this is how it was originally installed (and worked well until the Sungrow failure!). I have replaced the RCD just in case that was the issue but it still trips at start-up.

Any suggestions please?

One thing I'm not clear on (install instructions vague?) is: should I run a separate EARTH cable from the AC side isolator switch to the Solis inverter's case? Could not having this be causing the daily trip?

Thanks

 

[Norton3000]

Can you post up a pic of your CU?

Is the solar on a shared RCD board. What is actually tripping? Main RCD?

Thanks

Norton

 

[iainco]

Can you post up a pic of your CU?

Is the solar on a shared RCD board. What is actually tripping? Main RCD?

Thanks

Norton

Hi Norton, the middle RCD/main protected circuits keeps tripping at start-up. Hope that helps? Thanks.

 

[iainco]

Can you post up a pic of your CU?

Is the solar on a shared RCD board. What is actually tripping? Main RCD?

Thanks

Norton

...the solar has been wired into a spare within the protected circuits area so ends up tripping the house sockets, cooker, shower etc that are on the protected RCD?

 

[newfutile]

Some inverters leak a lot to earth and should not be on a 30ma (RCD) Residual Current Device especially a shared one for this reason.

 

[brianmoooore]

Dangerous as well. If an earth fault occurred, such as you making contact with live mains, the RCD should disconnect the power in a sufficiently short time to prevent you from being electrocuted. The RCD will switch off as intended, but power will still be being supplied by the PV array, until it detects the loss of mains power and shuts down as well. This time will be far greater than the time it takes to electrocute you.