I live (just out of town, overhead power lines) in Europe and suffering from RCD tripping from interferences on supply line.
I'm 100% sure, it's not a problem related to my wiring or devices in my house.
I have two RCDs in parallel and as a first aid, I got one (expensive) with automatic reclosing. It didn't resolve the problem because it recloses only 3 times at 3s intervals (stupid logic) and when the interferences present they usually come repeatedly over several minutes, sometimes even few hours. Rain or thunder is not causing it (might be related though).
Electricity company doesn't care about the problem. My record is RCD tripping 70 times in one hour, sometimes I have weeks without single one.
While I understand how RCD works, I'm not able to understand what type of interference from supply can cause it to trip and how. I have lot of electronics in my house and never got anything damaged from these events.
Can I filter them somehow?
RCDs I have are both 30mA typeA, one ABB and one Gewiss.
I had some trip because of bad heating elements, leaking to ground, in washing machines. Flipping the two hot wires to the element usually cured the problem.
Leo..
If the overhead powerlines really cause RCD tripping, i suggest you move house. If that much inductive current is generated in one or more of your electrical appliances, imagine what that does to your body. That is a seriously unhealthy situation.
Normally speaking i would say that what you describe is not very likely and there is a more likely cause like an insect somewhere that is causing a partial short or some fluid or a static layer surrounding some plastic that is conducting, but you seem adamant.
You should be able to even measure that sort of amount of EMF using a coil which should start to provide you with some power even though it is not connected to anything. (Tapping that is technically speaking 'stealing' but let's not worry about that.)
There is the chance of a device which has a coil in it that is affected by the EMF and of course the chance of a device that has some dodgy connection. If it really is the EMF you should actually see some other effects in your equipment, like TV & Radio, and you should be able to see a TL-light flicker as a result of it.
EMF is not healthy and prolonged exposure can cause all sorts of ailments.
It does sound strange because spurious tripping of an RCD circuit breaker is usually caused by an imbalance in the downstream circuit where 30mA (or whatever the rating is) goes missing somewhere.
My brother has a similar problem with multiple tripping of the breaker and it turned out to be that a garden slug had managed to get into a power socket mounted on an outside wall.
With the two breakers you have you could consider splitting individual circuits and see if the problem moves in that only one breaker continually trips.
Probably the term was incorrect, I mean that in our zone out of town, the lines are not underground. I don't have any lines over my house or garden.
Yes, I know that perfectly and that's the reason I'm asking help here. I don't understand what kind of interferences I can get from supply side and how it can affect the RCD.
To specify why I'm 100% sure:
I have measured residual current when tripping happens.
It's tripping even if I disconnect everything in downstream, all breakers down.
It's tripping usually both RCDs, even if they are on different circuits.
It's tripping usually also my neighbors RCDs when event occur.
A heating element has two wires.
If the internal earth leak is near one terminal of the element, say near the phase,
then swapping the wires moves the leak near the neutral wire, where the leak current might not trip the RCD anymore.
Leo..
Do you know what the earth/ground arrangement is and there are a number of these although it is not clear to me if any would contribute more to spurious triggering of an RCD. Earthing system - Wikipedia
Ok, measured residual current is not really any proof in this case, because it wouldn't catch the event, but I did it just to confirm that my leakage is not above normal levels and not anywhere close to 30mA when event happens.
Two RCD take care of different separate circuits in downstream, they are not in series.
All the loads in the house connect to one or another through individual line breakers on downstream.
My circuits do have common earth connection.
My neighbors have their owns.
You link was actually pointing me to some direction: Voltage fluctuation. We have very unstable voltage in our zone, so that could easily be the reason. We can have anything between 190V and 250V even if 190V is out of specs. I have not seen any relation to the events but fast fluctuation could be the problem..?
I didn't know that RCDs are sensitive to that.
Our neutral/earth setup is typical european one. Neutral-earth bond is done by electricity provider, no bonds on my side.
Leak balancing.
Yep, that trick saved once my barbeque party with a electric grill that had been kept on the terrace for long time accumulating humidity inside the heating element.
But you need luck as well.
You need to get your house wiring and connected appliances tested to determine if the RCD trip is genuine or false .
Trying to get around it tripping is pointless if you have a fault on your system.
@hammy is right, this is definitely worth talking to your electric company about because it is not normal and from what you describe it is a problem on the service side.
I remember a long time ago working in a house that was one in a terrace of "railway houses" in a rural part of England, someone had trapped a hot wire under the mounting screw of a fluorescent light fitting. This house did not have an adequate grounding system and every time the light was switched on it would trip the rcd (at that time called an elcb) of the neighbors house. Both houses were supplied by a transformer on a pole in the street.
Another very strange problem I had with a rcd, which is not your problem IMO but worth a mention, and this was a rcd in a lab that would trip when a certain spectrometer was in use. The instrument had a capacitor between the hot and the ground and the reactance of the capacitor passed enough current to exceed the trip current of the installed rcd.
Yep, I tried but they don't care. The line is old and it doesn't have capacity that it's supplying. That is one reason the voltage is fluctuating so much, we have nominal 230V, but during dinner time it's regularly coming down below 200V which is out of norms. That low voltage generally doesn't cause any problems, but I'm wondering if sudden drop or drop-raise could cause..
I live in a rural area, and we had a problem caused by a ground fault on the supplier side. The neutral to Earth connection was loose on a power pole, which led to significant voltages (I measured 77VAC with a multimeter) and current flow between the neutral lead and Earth ground in our home.
When alerted, the power company was very responsive and fixed the problem within hours, as those conditions are extremely dangerous. If you can document that, and the power company doesn't respond, get your local authorities after them.
A sudden drop or rise might be a culprit depending on what appliances are connected but with all breakers off no it should not happen.
Switching the breakers off and still tripping could also mean you have a ground to neutral fault, to do that test correctly you would need to disconnect the associated neutral wires. I am assuming both rcd's are upstream of the breakers.
To check that out you would need to unplug all appliances remove all light bulbs and led lighting or fluorescent's of each circuit you are testing, disconnect the circuit neutral from the main neutral wire then use an insulation resistance tester to check between ground and neutral of each circuit.
EDIT The reading should ideally be above 1 M Ohm
EDIT Make sure the panel you are working on is safe and electrically isolated
