RCD trips every morning between 08.00 and 09.00

[pgrbff]

The house has been rebuilt over the last 3-4 years, all the wiring is new as is the conduit it has been pulled through. It has been a total rebuild and I am very hands on, so I know what has been done and how it has been done.
The electrician came highly recommended, I have no doubt they would not cut corners and I trust them. Having said that, as far as I am aware they did no earth leakage tests when each stage was completed. I do not know if they are considered necessary or infact reqd. according to local regs. There are a couple of pics attached of main distribution board to give indication of quality of work. You will see that there is probably less detail than UK. You can still put a switch and a 240V socket next to a sink in a bathroom here.
In the last hour, with only 2 fridges, a freezer, modem and router plugged in the voltage has been as low as 200V and as high as 236V.
I have had a month to try and work out what might be causing it but there really isn’t anything I can think of.
My gut feeling is that it is external.
I am not trying to avoid the issue by fitting a restart, we regularly have short power cuts that cause the RCD to trip, I am trying to make life a little easier/safer while I try to determine the cause.
During the winter we operate a wood fire boiler and during power cuts I have to manually start the generator to stop the boiler, which is a sealed system, overheating. The restart would help here too.

 

[marconi]

Studying the wiring inside the consumer unit and the legends on the front, the main income is into the ENEL disconnector top left. It feeds the ds642p I referred to earlier. To determine if it is an active or passive type could you do a quick trial?

1. Turn off all the mcbs to the right of the ds642p.

2. Turn off the ENEL disconnector. Does the ds642P trip? If 'yes' it is an active and if 'no' it is a passive type.

3. Return all mcbs to closed.

if you discover it is an active type then you could ask the electrician to swap it for a passive type which does not trip for a'black out' = no voltage or 'brown out' = low voltage (which your fluke readings show you suffer).

 

[pgrbff]

Thank you. As soon as I can I will do as you suggested.
Just for a change the RCD in the granny flat tripped this morning, and the one in the main board didn’t. It is the switch top left corner in images attached.
The relays are for 2 plus switching of lights which operate on push to make light switches. Normal practice here.

 

[telectrix]

nice to see other european countries complying with the harmonised colours,...NOT..... like seems it's only the UK that does.

 

[pgrbff]

I don’t know UK or Italian regs but if I have understood the idea behind your comment; all wiring is single strand here, pulled through conduits. The way they wire lighting especially is completely different. You end up with a vast number of different colours to differentiate between circuits. Every bedroom has a switch either side of the bed to control the room lights amongst other things.
Maybe I have missed the point altogether.

 

[telectrix]

the basic "harmonised" colours are brown for L, blue for N. black or grey can be used for either but must be sleeved with appropriate colours. so where for example you have blues for L, it's totally non-compliant with the stupid eu colour scheme.

here we've been perfectly happy with red for L and black for N till eu made us use the all colours are grey in the dark idiocy. than God we're out of the eu as soon as the politicians get their arses moving.

 

[pgrbff]

I’m often surprised by the huge difference in rules given the EU. You still get 240V light switches and sockets in bathrooms here, i was also told that the Italian regs insisted I have a TV aerial socket in every room or the electrician couldn’t sign off on the job.
I used to live on the “high street” of a small town, there was a butcher next door. Twice a week at around 5am, right below our bedroom on the 1st floor, a small lorry would back up and unload a live cow. I would then hear the chains running through pulleys as it was pulled up by its back legs.
For years In the UK farmers complained about the long distances their livestock had to travel for slaughter and the stress it caused, all because of EU rules. They don’t seem to apply here.

 

[marconi]

I can only see one perhaps two Green/Yellow conductors inside the annex CU. None visible in the main CU. Are final circuits provided with an earth (circuit protective conductor cpc) which is insulated GY?

Do you have an earth electrode close to the house and connected by a thick GY conductor to the Main Earth Terminal(MET) one in each CU?

Do you occasionally water (yes) the earth electrode? The plastic inspection cover should also have holes in it to allow rain water in.

 

[pgrbff]

Yes we have a new earth electrode, it has a lid which isn’t waterproof.
Immediately below each consumer there is a box through which all the cables are pulled. The brighter image is the box below the main consumer unit.
All the GY in the consumer units are tied together, main one too, and pass down to the boxes below.
I once stayed in a small house in Greece where every time you touched the shower knob you received that little fizzle! They insisted all we had to do was water the earth rod. We moved out.
We are not in a particularly dry area. We have never felt it necessary to water the rod. The earth rod is directly below the consumer unit one floor below.

 

[telectrix]

Yes we have a new earth electrode, it has a lid which isn’t waterproof.
Immediately below each consumer there is a box through which all the cables are pulled. The brighter image is the box below the main consumer unit.
All the GY in the consumer units are tied together, main one too, and pass down to the boxes below.
I once stayed in a small house in Greece where every time you touched the shower knob you received that little fizzle! They insisted all we had to do was water the earth rod. We moved out.
We are not in a particularly dry area. We have never felt it necessary to water the rod. The earth rod is directly below the consumer unit one floor below.View attachment 50702View attachment 50703

those pics are very appropriate for Italy. spaghetti nightmare,coloured as a meat feast pizza.

 

[pgrbff]

I installed all the sockets, working alongside the electricians, they all have earths as do all the light fittings. They did all the switches.

 

[pgrbff]

It is also a very expensive way to wire a house. On the upside it does allow you to modify the wiring.

 

[pgrbff]

It is also a very expensive way to wire a house. On the upside it does allow you to modify the wiring.

 

[pgrbff]

My electrician left me a voicemail today and I think the problem of the main CU is solved.
The two black switches on the left, main switch, and the RCD are combined.
If the main switch fires, it takes the RCD with it. I assume that the main switch might go for either a low or high voltage?
If on the other hand, the RCD detects a fault the main switch will remain on.
The problem with the voltage fluctuations will be a difficult one to solve, they say the lines to my house are the heaviest permissible.
So a restart seems to be the only option?

 

[pgrbff]

those pics are very appropriate for Italy. spaghetti nightmare,coloured as a meat feast pizza.

I thought you might like a look at some of the plumbing too.