This depends on the design of the installation.
That relay could purely monitor the supply voltage, with a normally closed contact between N & E.
Then no signal from the inverter would be required.
Switch off the supply to the inverter MCB in the sub-DB, and listen if you hear the relay operate.
Thatās what I am worried about. Not only is that wrong (well, it is better than nothing I suppose), if that is the case, then the setting in the inverter will make no difference.
I donāt think there is any danger in trying that setting. If it is not wired, it will just do nothing. But I donāt know this inverter well enough to say with certainty.
Edit: If however it is wired correctly, and the relay DOESNāT pull in when he islands, then that might be a good sign, it might mean activating the setting will fix the bonding issue.
Because the RCD loses itās marbles when the grid trips, I suspect that will remain the case. Well, maybe a fast acting bond will helpā¦ maybe not.
Should be ticked.
Over 7 months now that I am not active in the field with installations. I only go to site to sort issues like this. I truly enjoy looking for and fixing Neutral faults on site. It takes time, that I dont currently have much spare of, but wish I could come help.
Iām going to guess that the RCD loses itās marbles when the relay closesā¦
Thank you all.
Just an update.
The installer will come and have a look tomorrow. If they find anything Iāll post it here.
FYI:
I intermittently trip the main switch 10+ times yesterday during the day to see if the leakage trip, still no trip.
Last night I also had load shedding again from 22:00 - 00:00 and it didnāt trip (external lights on, multiple internal lights, TV, etcā¦
Tripping the main switch doesnāt truly simulate what happens when there is load shedding.
Eskom trips a 3ph breaker that is upstream of the transformer that feeds you.
As your local transformer powers down, there is asymmetry of the collapsing flux in the windings which means a substantial current flows up/(down) the transformerās neutral.
The same asymmetry happens when the grid returns.
Sometimes your phase will be affected badly and sometimes not, it depends on what point on the wave the upstream switching happens.
In a nutshell, this means there is a voltage between neutral and earth, but because they are bonded substantial currents will flow for a short time. This is probably what is exposing your earth leakage.
So I think you need to megger the non-essential circuits because there is a high resistance earth fault and it is system bumps that are exposing it.
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Thank you Phil.
Just for my understanding.
So I think you need to megger the non-essential circuits because there is a high resistance earth fault and it is system bumps that are exposing it.
Is it something that is caused by the āmisconfigurationā of the main DB during the installation?
No. All heās saying is that the only way to properly simulate load shedding, is for Eskom, or your more immediate supplier to throw the switch on their side (several kilometers away). Then the effect of all that wiring and equipment is included in the result.
Simply throwing the switch in your DB is way too clean and doesnāt make these issues show up.
The equipment also behaves differently depending on exactly where the break happens. Think of it as two people jumping on a trampoline, and getting out of sync. If you come down onto the mat just as the mat is going up, the effect is a lot more jarring than it might be otherwise. The same sort of timing-related jarring stuff happens on the grid too.
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I have to guess at the configuration of the main DB.
To my mind, (the design I think has been used), the main switch wonāt kill the entire main DB, which I think is a ZA code violation.
But that of itself would not cause the E/L to act up.
From then on, there are a number of possible explanations.
And you have to rule them out systematically.
My default starting position is that the E/L is doing what it is supposed to do.
That is my default starting position because, more often than not, that turns out to be the case.
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Hello everyone.
The installer was here and they are happy with the inverter installation/configuration and also with the installation/configure of the DB board/s.
They tested leakage with a digital clamp meter and detected no leakages.
However, they did do a simulation of a leakage (multiple times) using a leakage testing tool and they got inconsistent readings when they did the tests. Readings between 30 and 35.
From my understanding, the inconsistent readings has to do with my earth leakage and they advised me to replace the earth leakage.
Iāve posted this video a few times, of myself doing a quick test. Donāt really like public speaking, of which this is an example (and it is in Afrikaans too, with our delicious accent). But it shows a leakage test using a clamp meter built for it, and how one appliance affects it.
I swear by this kind of test. Anything else is a little blind. If you donāt measure, you donāt know.
Yes, you must test the RCD. You must do an insulation test. But when those all come back with a good result, this is the ONLY way to quickly find out where the leak is.
While most sparkies do carry a clamp meter, very few of them carry one that can do this job though. Meā¦ I bought it out of sheer exasperation, because I feel threatened unless I understand the problem 
Edit: That DB has been redone, btwā¦ and the terrible shelf going across the middle of it was cut out too.
As far as I am concerned, the sparky just proved the E/L is not the problem, and if anything, it errs on the side of being too stable.
I doubt the leakage tester has been calibrated recently and 5mA inconsistency (of either device) is not the source of your problem.
You donāt mention that an insulation test (with a 500V Megger) was done. That is the test needed to expose poor insulation.
Remember that the earth fault can also be on an appliance that was not plugged in when the tests were conducted.
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A normal digital clamp meter is useless in finding these kind of issues. You need something like the one Izak used in his video. I have a different brand but they are awesome.
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Regretfully in your case this test is also useless. A proper insulation test is the only answer.
Where are you based
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Thank you Phil.
I do agree. Spoke to two other electricians that does this sort of installations. Their opinion is that it is because my lights are now on earth leakage and in their experience, most of the time, it is the lights that are causing this.
It feels like non of the electricians that were here, do proper testing. Iām at the stage where I want them to revert back to how it was, lights not on the earth leakage.
@JacoDeJongh Iām in Brackenfell, Cape Town.
Well, the culprit could still be found and fixed fairly easily.
However, there is a school of thought that certain light circuits should never be on E/L. Due to the dangers of being left in the dark in hazardous areas.