Earth Leakage Detector

[JohnW2]

I've ran an extension cable from upstairs, into the garage and plugged the treadmill in, no tripping. Upstairs is supplied by a TYPE 3 RCD. The treadmill also doesn't trip when connected to the downstairs sockets, this is connected to a TYPE C RCD

OK. That more-or-less rules out any major problem with the treadmill. However, it still leaves the possibility that there is some small 'leak' in the treadmill which adds to some other problem in the circuit normally used and/or which is enough to trip one RCD but not the others (due to differences between the RCD/RCBOs, even possibly a faulty one).

Kind Regards, John

 

[TheBinarySheep]

OK. That more-or-less rules out any major problem with the treadmill. However, it still leaves the possibility that there is some small 'leak' in the treadmill which adds to some other problem in the circuit normally used and/or which is enough to trip one RCD but not the others (due to differences between the RCD/RCBOs, even possibly a faulty one).

Kind Regards, John

I have tried the treadmill with nothing else connected to the garage circuit, and it still trips, so I'm not sure there are any devices which could also be causing a leak.

 

[JohnW2]

I have tried the treadmill with nothing else connected to the garage circuit, and it still trips, so I'm not sure there are any devices which could also be causing a leak.

Fair enough. In that case, if there were another leak it would presumably have to be in the wiring of that circuit (fairly easily checked by an electrician) or due to the behaviour of that particular RCD/RCBO (again, largely testable by an electrician).

Kind Regards, John

 

[Jadele]

have you looked in the back of garage socket for any problems

 

[TheBinarySheep]

have you looked in the back of garage socket for any problems

No, but I don't think there's any need, as I've tested the treadmill connected to the extension circuit, with the garage circuit completely disconnected from the RCD. The RCD feeds both the extension and the garage, I've completely disconnected the garage to rule out an issue with it's circuit.

Ideally I need to do it the other way, remove the extension from the circuit and see if it makes any difference.

 

[JohnW2]

No, but I don't think there's any need, as I've tested the treadmill connected to the extension circuit, with the garage circuit completely disconnected from the RCD.

When you say 'completely disconnected', do I take it that you disconnected both line/live and neutral?

Kind Regards, John

 

[TheBinarySheep]

When you say 'completely disconnected', do I take it that you disconnected both line/live and neutral?

Kind Regards, John

Yep, disconnected them both completely.

 

[Jadele]

So is the garage socket a spur off the ring that goes to the extension

 

[TheBinarySheep]

So is the garage socket a spur off the ring that goes to the extension

No the garage is connected directly to the RCD, and so is the extension. They're both ran directly from the RCD.

 

[Jadele]

May be more issues then here, is the garage wiring 4mm then? . Its either a ring from the garage through the extension or two radials. If its 2 radials the breaker should be a max of 20amp and the spark should not have upped the breaker size.

 

[TheBinarySheep]

May be more issues then here, is the garage wiring 4mm then? . Its either a ring from the garage through the extension or two radials. If its 2 radials the breaker should be a max of 20amp and the spark should not have upped the breaker size.

I'm going to take a stab and say the garage is a radial while the extension is a ring?

I can open up the consumer unit, and connected to the RCD I can see three sets of cables.

The first set is red/black - the garage

The second and third set of cables are both blue/brown and these are for the extension. I'm assuming a ring?

 

[Jadele]

Well If you disconnect the black and red and power the circuit the black and red should have no power on them. Then if you then disconnect a set of blue and brown and put power on you should still have power on the two disconnected ends if thats a ring. Need to very careful doing that obviously. Either way the garage isn't ideal like that especially if the garage has more than one socket.

If it does only have one socket then its not that bad but imo due to the intended use it should have a lower value breaker.

 

[TheBinarySheep]

Well If you disconnect the black and red and power the circuit the black and red should have no power on them. Then if you then disconnect a set of blue and brown and put power on you should still have power on the two disconnected ends if thats a ring. Need to very careful doing that obviously. Either way the garage isn't ideal like that especially if the garage has more than one socket.

The garage only has one socket. Do you think it would be worthwhile running a fused spur from one of the sockets in the extension and running a new cable into the garage. Would that be a little more ideal?

 

[Jadele]

If the extension is a ring then it would be better because the cable would be better protected. It sounds like at the moment its a long spur from the Extension ring at the moment. While thats not wrong as such it would be better to extend the ring of the extension in to the garage.

 

[JohnW2]

I'm going to take a stab and say the garage is a radial while the extension is a ring?

If that is the case (and it seems credible from what you go on to say about the acbles), then another way of describing that is as a 32A ring with an unfused spur (supplying the garage socket) originating from that ring at the RCBO. Given that you only have one socket in the garage, that would be an acceptable arrangement, even if the cable to the garage were only 2.5mm².

Kind Regards, John