EV charger causing ground overheating

[redfox88]

Had an EV charger installed in July last year. It’s wired directly off the mains.

Since end of November anytime I plug the car in to charge, the earth/ground wire in the cabling in other appliances in the house is overheating and melting components of the appliance until the main RCD trips.

Has anyone ever seen or heard this happening before and what could be happening?
Even appliances isolated by switch fuses, when off are getting impacted. It’s concerning.

Electrician has been doing tests but is not quite sure what could be causing the fault

 

[Risteard]

There are differences between Irish and UK regs and as far as I know an earth electrode is required for the whole installation under Irish regulations when a TNCS supply is used.

Correct. Every installation requires an Earth electrode.

 

[plugsandsparks]

Just had a browse on some chargers and the Tesla for example would have seen the rod and concluded no problem, assuming Earth fault detection was enabled for that install. I am pretty sure a Zappi would have gone nuts either with under-voltage L-N or N-E v Diff

Interesting though how to melt your house cables,

 

[redfox88]

UPDATE: came home from a couple nights away to no power in the house. The main RCD had tripped.
I traced issue to blow 3A fuse in the switched fuse spur powering the gas boiler. I replaced the 3A fuse but the boiler didn't power.
Further inspection inside the boiler should me that the small fuse inside the boiler had blown.
And further inspection again showed me cabled inside the boiler had been overheating. The loom connecting all the components was melting, and the cables connecting those components to the pub had been melting too. Absolutely no idea why. Power to boiler is sound and no issues anywhere else on the circuit except for the boiler.
Gas boiler installer and repair guy is calling to replace entire boiler as opposed to just components and wiring from the last time round.

 

[James]

It sounds like a possible fault with the supply N
this may be somewhere along the supply cable or even at the substation.
a call to your energy supplier emergency hotline is the best place to start.

 

[redfox88]

Again? Really? They've just installed (Jan '23) new fuse and meter joining in new L & N into the house

 

[baldelectrician]

The installer should have confirmed the Ze (external earth loop) with the rest of the property off and earths disconnected. The fact that was all boxed in means this was not done

As a matter of urgency get the main gas and water pipes bondedm this way stray earth currents are likely to go through the bonding and not your boiler wiring loom

I would also suggest you contact the car charger manufacturer and ask them to send someone to asess the situation

I also noticed the EV installer appears to have installed a Hager RCD inside an Eaton unit- not good

 

[RoryDickerson]

Had an EV charger installed in July last year. It’s wired directly off the mains.

Since end of November anytime I plug the car in to charge, the earth/ground wire in the cabling in other appliances in the house is overheating and melting components of the appliance until the main RCD trips.

Has anyone ever seen or heard this happening before and what could be happening?
Even appliances isolated by switch fuses, when off are getting impacted. It’s concerning.

Electrician has been doing tests but is not quite sure what could be causing the fault

It's difficult to diagnose the exact cause of the fault without more information, but overheating and melting of the earth/ground wire in the cabling could indicate a short circuit or other electrical fault. The fact that other appliances in the house are also being impacted suggests that the issue may be related to the electrical system in the house rather than just the EV charger.
It's possible that the EV charger is drawing more power than the electrical system is designed to handle, causing a voltage drop and increased resistance in the wiring. This could cause the earth/ground wire to overheat and melt, and could also impact other appliances in the house.
It's important that the electrician continues to investigate the issue and performs comprehensive testing to identify the root cause of the problem. They may need to check the wiring and connections throughout the electrical system to ensure that they are properly sized and installed, and may need to perform load calculations to ensure that the system can safely handle the additional load from the EV charger.
In the meantime, it's recommended that you stop using the EV charger until the issue is resolved to avoid further damage to the electrical system and appliances in the house.

 

[brianmoooore]

Another Bot alert!
..... ......

 

[Risteard]

I also noticed the EV installer appears to have installed a Hager RCD inside an Eaton unit- not good

There is no Annex Zb derogation within I.S. EN 61439 so no conditional short-circuit rating for type tested units etc. so there is no prohibition on that. Of course this is assuming that it had been connected correctly e.g. supplied with tri-rated panel flex outer something similar.