Melting Adapter & Tripping - Cause?

[dishman]

Hello, just a follow up to my recent post about my battery charger adapter melting.

I was getting concerned that I had an electric issue after an adapter I was using to charge a battery pack melted on me and tripped out the sockets switch in the consumer unit. The adapter seemed to work fine charging in another property which has an old manual fuse box. It melted after charging for only 15mins in this more modern house. It tripped the circuit and blew the fuse in the four plug extension.

Separate to this issue I had also been concerned that there was a possible underlying issue as my electrics tripped out as when I used the tumble dryer. The circuit trips out if I used other electrics (kettle, oven etc.) which plugged into different sockets but used at the same time as the tumble dryer.

Although the tumble dryer is plugged in to a four way extension (not ideal) the other devices plugged into that do not exceed 13amps (in fact they are not usually on if the dryer is on).

Another thing I notice i that all the lights flicker when I turn an electric item with a high power draw on. This happens with the kettle, vacuum cleaner, dryer etc. The lights dim slightly. Is this normal in houses with modern electrics? I always thought this was a sign of bad electrics...

This is a list of the trip switches and RCD in the unit

B6 (Lighting)
B20 (Downstairs Sockets)
B32 (garage)
RCD 80A 30mA WRS80/2

B16 (Secuirty Alarm)
B32 (Cooker)
B16 (Sockets)
B16 (Sockets)
RCD 80A 30mA WRS80/2
Main Switch

I will get an electrician in if there is an issue. I would not think of mesing with anything myself. But was intrigued if anything stood out as being a bit wrong.

Many thanks

 

[Aragorn84]

circuit layouts are slightly peculiar, but i wouldnt think its any cause for concern.

Only one lighting MCB for a two story property is a bit unusual

Similarly, sockets on a B20 and B16 are a bit unusual, but certainly nothing wrong with that in itself. It may however indicate that some circuit that was originally a ring has been modified or altered potentially due to a fault.


I too got the slightly flickery lights when high load applicances were turned on. Its fairly typical i think, and went away when i replaced all the incandescent lamps with CFL's.


There certainyl sounds like something odd with the tumble dryer, or its associated circuit. Only tripping when high loads are applied suggests a neutral to earth fault, either in an applicance or in the fixed wiring. You'd really need an electrician to do an inspection to find out whats going on there.

 

[JohnW2]

Similarly, sockets on a B20 and B16 are a bit unusual, but certainly nothing wrong with that in itself. It may however indicate that some circuit that was originally a ring has been modified or altered potentially due to a fault.

That's quite possible, but some people favour multiple radial sockets circuits. Why 16A for a couple of them, rather than 20A (which would very probably be OK) is less clear.

Kind Regards, John

 

[dishman]

Many thanks for the replys.

Just to clarify, how would the differance of a 16amp mcb compared to a 20amp?

Would that mean each socket on that particular circuit has a maximum rating of either 16amps or 20amps? Or would it mean that the maximum on that whole circuit is 16 or 20 amps?

 

[JohnW2]

Many thanks for the replys. Just to clarify, how would the differance of a 16amp mcb compared to a 20amp? Would that mean each socket on that particular circuit has a maximum rating of either 16amps or 20amps? Or would it mean that the maximum on that whole circuit is 16 or 20 amps?

The latter of those - the MCB rating determines the maximum on the whole circuit.

Kind Regards, John

 

[dishman]

Oddly It just tripped out this morning. It seems that just one of those b16 socket mcb trip out all the electrics in the kitchen including the lights, some of the sockets in the front room (tv area specifically) and all of the sockets upstairs.

This seems to be very odd for all these sockets to be reliant on just one breaker? I would assume this will be why it trips easily?

Is this normal or very odd?

 

[JohnW2]

Oddly It just tripped out this morning. It seems that just one of those b16 socket mcb trip out all the electrics in the kitchen including the lights, some of the sockets in the front room (tv area specifically) and all of the sockets upstairs. This seems to be very odd for all these sockets to be reliant on just one breaker? I would assume this will be why it trips easily? Is this normal or very odd?

Do you mean that one of the RCDs tripped? If so, you would expect it to take out all the circuits (MCBs) protected by that particular RCD. If the description you gave is correct, than if it took out the lighting (you described only one lighting circuit, on the first RCD), the only other circuits that should have been affected would be the 32A 'garage' one and the 20A 'downstairs sockets' one. Is it possible that the kitchen lighting is not supplied from the one lighting circuit you mentioned?

What did you have to reset after the trip? If more circuits that I describe above were taken out by one RCD tripping, you probably need an electrician to work out what is going on, since that shouldn't happen.

Kind Regards, John

 

[dishman]

Sorry if I am getting terminology cross wired.

Basically what happened. Tumble dryer was on and a few other devices. Next everything went off. This comprised off all the sockets and lighting in the kitchen (apart from the cooker I think), some of the sockets in the front room and all the sockets upstairs.

When I looked at the consumer unit only one of the breaker had tripped. Specifically one labelled sockets with the rating B16. On the list I copied down this was the 8th one down. The switch just dropped down as I said and I flipped it back up and everything is fine again.

But as I said, this single breaker labelled "sockets" seems to control a lot more then just sockets.

I have not needed to touch any of the RCDs which have smaller yellow type push buttons.

Is that any clearer.

 

[JohnW2]

Basically what happened. Tumble dryer was on and a few other devices. Next everything went off. This comprised off all the sockets and lighting in the kitchen (apart from the cooker I think), some of the sockets in the front room and all the sockets upstairs.
... When I looked at the consumer unit only one of the breaker had tripped. Specifically one labelled sockets with the rating B16. On the list I copied down this was the 8th one down. The switch just dropped down as I said and I flipped it back up and everything is fine again. ... But as I said, this single breaker labelled "sockets" seems to control a lot more then just sockets. ... I have not needed to touch any of the RCDs which have smaller yellow type push buttons.

I think you definitely need an electrician. What you describe is all wrong. One 16A MCB tripping should not result in loss of all of what you describe.

Kind Regards, John

 

[bernardgreen]

B6 (Lighting)
B20 (Downstairs Sockets)
B32 (garage)
RCD 80A 30mA WRS80/2

B16 (Secuirty Alarm)
B32 (Cooker)
B16 (Sockets)
B16 (Sockets)
RCD 80A 30mA WRS80/2
Main Switch

Are both the RCDs in the ON position ?
Or has the live connection to one of them failed ( loose terminal ) ?

If the RCD that feeds the bus bar on which the B16 trips is OFF then it is possible ( due to a wiring error ) that the B16 which trips is back feeding the bus bar and all the other MCBs on that bus bar. It will trip due to the load on that bus bar ( via the other MCBs on it )

 

[JohnW2]

If the RCD that feeds the bus bar on which the B16 trips is OFF then it is possible ( due to a wiring error ) that the B16 which trips is back feeding the bus bar and all the other MCBs on that bus bar. It will trip due to the load on that bus bar ( via the other MCBs on it )

That's one possibility (out of many). As I said, the OP definitely needs an electrician.

Kind Regards, John

 

[ekmdgrf]

Similarly, sockets on a B20 and B16 are a bit unusual, but certainly nothing wrong with that in itself. It may however indicate that some circuit that was originally a ring has been modified or altered potentially due to a fault.

That's quite possible, but some people favour multiple radial sockets circuits. Why 16A for a couple of them, rather than 20A (which would very probably be OK) is less clear.

20A is as far as you can push a 2.5mm radial. So possibly the other two circuits had derating factors. Another possibility is that the installer used the breakers that he had to hand.

The alarm is on a B16 and I doubt very much that it pulls anywhere near 16A. JohnW2, should the installer really have fitted such a large breaker?</In-Joke>

 

[JohnW2]

20A is as far as you can push a 2.5mm radial.

If the cable is clipped direct, and if you can find a 25A MCB, that would actually be OK.

So possibly the other two circuits had derating factors. Another possibility is that the installer used the breakers that he had to hand.

Indeed. I'm inclined to suspect the latter (or a lack of understanding!).

The alarm is on a B16 and I doubt very much that it pulls anywhere near 16A. JohnW2, should the installer really have fitted such a large breaker?</In-Joke>

The official answer is obviously that it depends on the cable (and installation method). A non-lighting circuit should not have smaller than 1.5mm² - which, if clipped direct, would be fine on a 16A MCB. Anything larger than 1.5mm² would virtually always be fine on a 16A MCB, regardless of installation method. Whether it makes sense to have a 16A MCB for an alarm (whatever the cable) is a different matter!

Kind Regards, John.

 

[dishman]

Really appreciate the advice guys.

So as I thought, it is probably best to get an electrician to do a full test of the current set up.

Not sure about the RCD thing. I am assuming if there was a connection fault they automatically visibly trip. So even if the wiring was bypassing it someway as you suggested, it would still show as being tripped. They both look on and active to me.

However here is a nice image of the set up. Maybe you guy can glean something from it that I may have missed.

View media item 75469
Is the way it is set up dangerous in anyway? It has been like this for years....

I am under the impression that as long as it trips out, it shows it is doing its job. However the house may just be badly/inconveniently wired/installed?

 

[JohnW2]

So as I thought, it is probably best to get an electrician to do a full test of the current set up.

That would certainly be my advice.

Not sure about the RCD thing. I am assuming if there was a connection fault they automatically visibly trip. So even if the wiring was bypassing it someway as you suggested, it would still show as being tripped. They both look on and active to me.

If the wiring is incorrect, then almost anything is possible and it's impossible to speculate.

However here is a nice image of the set up. Maybe you guy can glean something from it that I may have missed.

That hole next to the left-hand RCD is potentially dangerous and needs covering with a blanking plate. Was there ever an MCB in that position?

Is the way it is set up dangerous in anyway? It has been like this for years....

What you describe seems very odd so, as above 'anything is possible', including situations which could be potentially dangerous. As I'm sure you will appreciate, there's really no point in our trying to speculate from afar - someone needs to 'get their hands on' your electrical installation.

Kind Regards, John