Hi all

My system was installed in winter and has been running flawlessly until now. Since our first storms started two days ago in Gauteng - where I live especially heavy lightning and thunder - the main DB EL trips as soon as there is any thunder/lightning in the vicinity.  I have isolated the issue to the solar as when I shutdown the solar breaker on the DC DB the system runs no problem through the storm.

Any ideas what may be causing this?

Could it be poor grounding of the solar panels?

Cheers

Douw

 

 

Edited December 9, 20223 yr by Douw G. Gerber

Read this post - I know for a fact my panel frames are not earthed - could this be the issue?

 

 

more than likely poor grounding of your system and solar panels

Sunsynk 5kw

2x Dyness 4.8 LifePo batteries

6x canadian solor 545w and 12 x 275W

Feedback: Proper earthing of the solar panels seems to have resolved the issue.  Had lightning the last few nights with no trips.

Yes proper earthing is very important, it prevents such things. We at Green Air (Cyprus) always make sure the earthing part is always done properly. 

19 hours ago, Douw G. Gerber said:

Feedback: Proper earthing of the solar panels seems to have resolved the issue.  Had lightning the last few nights with no trips.

Are you running your earthing to the main earth connection or a separate rod in the ground?

There appears to be conflicting information of what can and should be done. Read on the forum the other day that code specifies the earth should be run to the mains earth from the panels and other conflicting info that says it should be isolated to it's own ground rod. 

 

My Opinion it that there is only one Earth. If you install lighting rods this should also be connected to your main Earth. 

Sorry I dont have answers and I am not in a position of knowledge to debate with Jacques 🙂 - we ran an earth wire from the panel frames to a rod.  The problem seems to have been solved.

You need to test the Earth leakage.

On 2022/11/04 at 6:17 PM, Clint said:

You need to test the Earth leakage.

Hi there Clint - can you maybe be a bit more specific here?  Using the button on the EL to test does trip it.

The nuisance tripping is back - only happens when it rains though.  It is random though becuase it used to be only when there was heavy lightning - did the earthing of the panels and that seemed to have sorted it at the time because we had a couple of big storms with lots of rain and no trips.  Today had a lite drizzle and it tripped again.

This is the earth leakage conntected to grid before the inverter.

Also to note - this only happens if my solar DB breaker is up - day or night - when it rains.  It does not trip if the solar breaker is down.

Thanks

Douw 

Edited November 23, 20223 yr by Douw G. Gerber

What inverter? Axpert?

On 2022/11/22 at 10:27 PM, Douw G. Gerber said:

Hi there Clint - can you maybe be a bit more specific here?  Using the button on the EL to test does trip it.

The nuisance tripping is back - only happens when it rains though.  It is random though becuase it used to be only when there was heavy lightning - did the earthing of the panels and that seemed to have sorted it at the time because we had a couple of big storms with lots of rain and no trips.  Today had a lite drizzle and it tripped again.

This is the earth leakage conntected to grid before the inverter.

Also to note - this only happens if my solar DB breaker is up - day or night - when it rains.  It does not trip if the solar breaker is down.

Thanks

Douw 

Is your inverter protected by this earth leakage (eskom >>> earth leakage >>> inverter), if this is the case then this may be your problem. 

It is recommended to not have your inverter protected by earth leakage but to only have the loads protected. so your power should flow as follows 

 

• eskom >>> main breaker >>> inverter >>> earth leakage a >>> essential loads
• eskom >>> main breaker >>> earth leakage b>>> non essential loads

where earth leakage a and b are two separate breakers. 

 

PS. I have not included some protection devices (like MCB's) above as the above example is just to show where the earth leakage should be placed.

PPS. My system has the solar earth and AC mains earth connected to the same grounding rod, though I do not have the experience to say with confidence that this is the correct and best practice method. 

 

Edit: On second thought, I feel confident enough to say that your inverter should not be fed from earth leakage, here is a quote from Victron Wiring unlimited

"An RCD must be mounted before the loads in an electrical installation. In reality this means that the RCDs have to be mounted before the installation is split up into different groups. If an inverter or inverter/charger is used, the RCD should come after this, otherwise there will be no earth protection while the inverter is operational. Consumers that are only operational when connected to shore power will need their own RCD."

 

Edited November 25, 20223 yr by Basil Katakuzinos

If the inverter is fed from an Earth Leakage then it for some reason trips when it rains.

 

I had a client, 8kw Sunsynk, panels earthed to main earth. Fine for months, then the rain came and instant trips of the earth leakage which was the main switch. 

 

I took the feed to inverter off the earth leakage and all fine.

 

I believe the negative (-) of the panels and the earth of the AC (same earth) connect to then have a negatively earthed DC system. It is my theory and I am not sure if that is the case and yet to test. 

 

Look inverters dont need to be fed from an earth leakage so taking it off is fine. 

Edited November 25, 20223 yr by Dylboy

Hi Douw

As a registered electrician I have a dedicated earth leakage tester.

I have replaced numerous earth leakage circuit breakers that only trip when there are electrical storms normally the old Heinemann brand.

I agree with the other comments that you must connect the earth leakage after the inverter.

Thanks chaps

I have my electrician coming this week to rewire it as suggested.

@Clint - the main E/L is a Hager - installed around 2017 so should still be good.

Update:

Changed the wiring as suggested - big storms etc last night and so far so good... Will let you guys know in a bout a week if all is good.

Wired like this now:

• eskom >>> main breaker >>> inverter >>> earth leakage a >>> essential loads
• eskom >>> main breaker >>> earth leakage b>>> non essential loads

Thanks for the input and assistance.

 

Edited December 9, 20223 yr by Douw G. Gerber