[glynnredhead]

(Mods: Apologies if this is in the wrong forum, feel free to move)

Hi,

I've just bought a new Belkin AV Isolator surge protector, but I'm having some problems with my mains box tripping. I dont know enough about such things to know if/where there is any fault, so would appreciate any thoughts. The house is a 50s build, with extensions added in late 80s and 2008, with a separate ring mains for the extension.

I previously had a (cheap and probably not very effective) surge protector plugged in protecting my TV/AVR etc, and am trying to replace it with the Isolator.

However if I plug the surge protector (with or without any devices plugged into it) into any socket in the extension, the circuit breaker (RCD?) for the extension immediately trips. This happens whether or not the wall socket is switched on. This doesnt happen with the old cheap surge protector.

If I plug the isolator into a wall socket in the 'old' part of the house, nothing trips. The correct lights come on on the surge protector, indicating power and that the surge protection is in effect.

In summary, I havent seen any previous problems with the mains, and the Belkin Isolator seems fine on a different ring, but immediately trips the mains every time I connect it to the extension mains ring.

Any thoughts on if/where the problem might lie and how to fix this?
(short of running an extension wire across the house!)

[ben.bayliss]

With the RCD/trip switched **OFF** I'd be tempted to take a look at the socket on the wall, and inside the plug on the surge protector to look for bad connections etc.

Sounds like something is wrong with your wiring to me..

[Dude a llama]

If your RCD is tripping it is doing it's job, sounds like there could be a fault with the new surge protector. Check that the plug is wired correctly if it's not moulded, maybe test the surge protector at a friends or neighbours. If the electrics trip at another property then take it back and change it.

[deckingman]

Can you just confirm the folowing please? Is the extension definitely fitted with an RCD rather than an mcb? Is the "old" part of the house also fitted protected with an RCD or is this mcbs or even old fashioned fuses?

From what you say, I believe that this will be the case. As the RCD trips with the unit fitted to any socket in the extension, then I'd say that the fault would lie with the unit and is probably an earthing fault.

[glynnredhead]

Thanks for the input so far:

The wiring for the whole house comes to a consumer unit under the stairs. The wiring for the extension (a mains ring, a a lighting ring, an electric shower, and smoke alarms iirc) are all together in one group on the left side, with an RCD protecting them.

The rest of the wiring (ie the other parts of the house) are in a larger group, but dont have an RCD. It has a separate switch for each ring, with a master switch on the end. No old fashioned fuses at all afaik.

something like this:

--------------------
IIII R IIIIIIIII M
--------------------

I'm not at home at the moment, but will have a look at the surge protector tommorow when I'm back. If its an earth fault, should this be detectable with a normal multimeter?

I dont think theres any problem with the wall socket itself, as it happens with other sockets on the same ring. Possibly other appliances on the ring though, I'll try unplugging everything and connecting in just the surge protector and see what happens.

[glynnredhead]

So...
I got home lastnight and dug out my multimeter. When I tested, there was no connection between Earth and Live (which is obviously what I was hoping) but there IS a connection between Earth and Neutral, which doenst sound right to me?

The plug is moulded, but I took the cover off the unit and had a look inside for any stripped or broken insulation etc, but couldnt see anything. Is it possible that the Earth-Neutral connection is by design, or is that a definite fault?

[deckingman]

Hope you appreciate this. Just checked my Belkin PureAV surge protector and there is no continuity between Neutal and Earth. So it's a faulty unit you have.

[glynnredhead]

Cool thanks!
Wasnt expecting anyone to be able to actually check, just confirm principles, but thats even better, so yes, big thanks.

That clears that up then, I'll see if I can get a replacement.

Cheers

[glynnredhead]

Just as a follow-up, thought I'd post the resolution of this.

I called Belkins customer support, who were extremely helpful, and RMA'd the unit to them last Friday, and received a brand new replacement by courier yesterday (so less than a week).

I checked the replacement unit and as deckingman advised, there is no Earth-Neutral continuity. I plugged it in, and nothing tripped. I've now got all my AV stuff running through it no problem.

Thanks again to deckingman for going to the trouble of checking. Thanks also to Belkin for sorting this so quickly and easily, and I'd definitely buy again.

[deckingman]

Thanks for the feed back. Glad you got sorted.