ELCB Trips With Laptops

[andrew1210]

Hi, first post

The ELCB in my house seems to be very sensitive, it tripps whenever a laptop is plugged in (mines, friends and washing machine repair man's too) is this a fault with the ELCB not coping with the laptop or could there be a deeper fault. Strange thing is, it never seems to trip with anything else, just laptops!

It doesn't bother me that much, it's just annoying!
Thanks in advance for any help

 

[Taylortwocities]

Its not unusual.
The circuits that the RCD protects already have an amount of earth leakage and the laptop's power supply (which adds some more earth leakage) tips it over the threshold and it trips.

Your consumer unit and/or the attached circuits may need some attention - you may have an appliance, or something like an immersion heater, that is faulty.

Alternatively the RCD may be out of spec and trips at too low a current. In my experience the problem is more likely to be one of the above.

 

[RF Lighting]

What is the rating of the ELCB?

Do you know if it is a current operated type, or a voltage operated type?

Does it trip if you plug your laptop into any socket in the house, or is it just specific one(s)

How long have you noticed it doing this for?

 

[andrew1210]

It's a Wylex, all it says on the front of it is Cat: WES63/2, 30mA Trip
Not sure if this helps tell if its voltage operated, this is all it says, the laptop's trip on any socket, even tried different circuits (kitchen ring) and it stills trips. Also, it doesn't trip every time only sometimes, and it's been doing it since I got a laptop three years ago

 

[andrew1210]

Looking over my reply, I assume It's a Current operated type, since mA, refers to current , Also the installation dates from app. early 80's

 

[Hibbo]

As the others have said, it sounds like you have significant earth leakage somewhere, and the laptop PSU (which leaks to earth under normal operations) is pushing it over the tripping threshold.

It could be a faulty appliance somewhere (typically something watery) of a breakdown in insulation resistance somewhere.

Try disconnecting everything in your house, plug in TWO laptops (to bring the leakage up a bit) then switch things on and see if anything in particular causes the trip. This is not a great or accurate test, but it's all you can really do without getting an IR tester (or even better a spark with an IR & RCD tester)

 

[Steve]

the laptop PSU (which leaks to earth under normal operations)

Some do, some dont. Some laptop PSUs dont have an earth connection.

 

[andrew1210]

Hi, just to complicate things (or maybe not)

The Laptop has also tripped the ELCB in next doors house when plugged in next door (the installations are linked in some way via a wire in the loft running through the fire wall) but never in any other houses I have tried it in, including another neighbour and a relative in the same area with identical CU etc... Does this surface any other explainations or could it just be a coincidence?

Thanks so far to everyone who has helped

 

[BigJon]

Do you know what kind of cable it is?
what does the cable look like?

 

[andrew1210]

It looks like standard grey PVC cable, (the type used in ring circuits etc) I also checked my grans house down the street, she also has this cable running from the CU in her house to the CU in next doors

 

[RF Lighting]

That sounds very wierd indeed.

Any chance of a couple of photos?

 

[BigJon]

Hi, Sounds odd, are you sure it goes to your neighbours Consumer unit and not just down the wall to one of your power/lighting outlets?
Can you trace where it comes from in your house.
Have you traced where/what it connects to in your neighbours house?

 

[andrew1210]

Nope, just assumed it was going to her consumer unit as it deffinately comes from my one/my grans in her set-up. About a year ago, we had Homserve out on a job under our Electrical cover plan, as our ELCB refused point blank to reset, it turned out to be the neighbours, who were on Holiday, and theres tripped, ours would not re-set until theres was reset. Also, sometimes when the laptop does trip the ELCB, next doors ELCB also trips.

The Homeserve engineer put it down to "A shared earth connected by this 'linking wire." He said this was sometimes found in older setups.

I could not fully understand what he meant though as he only had "a 30min time limit" as it was an out of hours job.

 

[bongos]

About a year ago, we had Homserve out on a job under our Electrical cover plan

This is your first problem.

So did they actually sort the problem or just give you some comments about the fault being next door?

EDIT: Do a search on the Electrics UK forum with the word "Homeserve" and see how highly they are regarded by the sparks on here. It sounds like their homecover is designed to get your power back on any way possible, not actually sorting a possible fault with your wiring.

 

[andrew1210]

Yep it was a Sunday and the guy could not get out of the house quick enough "oh I, the problem is deffinately next door, and I need to go as i'm approaching my time limit"

I Left it at that as it has never tripped again for no reason (other than laptops