PLZ HELP ELECTRIC TRIPPING OUT

[Lectrician]

The MEM RCD's will trip if the neutral goes open circuit or high resistance.

If your meter is also reporting this type of fault (posh meter - never seen that before), then you can assume you have a neutral fault to your property. Surprised that your supplier didn't send anyone out if that is the message your meter gave?? A lost neutral on a supply is highly dangerous, especially on a PME supply.

RCD's in my experience are more likely to trip due to a fault on any circuit, but a large(ish) overall current draw. Any current inbalance will trip it, and this could be due to a N to E fault any ANY cct on the RCD, or a fault from L to E on an isolated cct due to internal element/load resistance to neutral.

 

[Alan123]

what can cause a neutral fault???? a cooker ?? water heater??? because like i said before the black wire on the cooker switch was burnt out so must have overheated?? how do you fix this neutral fault and is it exspensive????? the electric comp said that the fault was internal and i need to get an electrician (great help)
Alan

 

[Alan123]

still thinking the cause is down to the water heater or boiler
when i switch on the cooker mcb all is ok but when i turn on the water mcb then turn on water switch in kitchen within 5/10 mins rcd trips out but why dont the mcb's trip out???? the rcd does not trip out when the water in the kitchen is turned off only when switched on does make a difference??
also why is the water only got a B16 fuse in ands the others have a B32??
is this right??
cheers alan

 

[JohnD]

- yes, it quite likely is the water heater, either a water fault making the electrics wet, or an electrical fault. I am not sure, when you say "water heater" if you mean an immersion heater in a hot water cylinder, or a gas boiler of some kind. But whatever the thing is that, when you turn it on, causes the RCD to trip, is likely to be where the fault is.

- MCBs do not trip from earth leakage, that's what the RCD is for. MCBs trip in the event of a large overload, or a short circuit.

- the water heater has a 16Amp fuse. In most houses, that is used for an immersion heater, which has a load of about that amount. Because it is a single appliance on its own circuit, it does not need to be any higher. The socket circuits are 32A because you might have plugged into them, at the same time, several large appliances, like a washing machine, tumble drier and fan heater, and the socket circuit is designed to have capacity for all this load.

I think from what you said that you have a gas boiler to heat the water, and that is what trips the RCD? A gas boiler uses very little electricity, since the heat is obtained from gas and the electrical devices are only ignition, timer, pump and so on.

If you have a wiring fault on your cooker circuit, it could possibly be contributing to the problem, because the RCD will trip when leakage reaches 30 milliamps (0.03 of an Amp) but this can be made up of one big fault; or two faults at 15 mA each, or three faults at 10mA each, or ten faults at 3 mA each, or one fault of 29mA and another of 1mA. Usually there is a general low level of leakage, and one additional faulty appliance will push you over the edge. In your case I am sure the first thing to invesigate would be the water heater.

Having a good idea of where the fault lies helps you call out the right sort of person. If it is a fault in a gas boiler, you need a boiler engineer, no-one else can do it. If you had a faulty immersion heater, you'd need a plumber. If you had a wiring or switching fault, you'd need a qualified electrician. Earth faults can be quite difficult to track down, so I hope you have a single easily identified cause.

 

[Alan123]

ok thanks for the info on rcd and mcb's
the thing that i switch on in the kitchen to heat the water is
1- we turn on the central heating switch (the one with a little red light on)
which has a 3amp fuse in it.
2- we then press the water constant button on the central heating control unit. the other options on this unit are -water timed ---water off---heating constant---heating timed---heating off
the make of this is a switchmaster 805
it is only when we press the water timed/constant button that it trips out
are you any the wiser to my problem????
cheers Alan

 

[JohnD]

From your description, I would suspect either the boiler, or the boiler controls, but I can't see it so I could be wrong*. If I were in your position, my first call would be a boiler engineer. If you went for an electrician first, he could probably tell you for sure if it was the boiler, but if it was, you'd then have to call out the boiler engineer you could have called in the first place, with additional cost and delay.

If it is the boiler, a skilled man will often know, with your particular model, where to look and how to fix it.


If you have got an immersion heater and a hot water cylinder, then I would switch this on until you get the fault fixed, then you won't keep having your electricity switched off.







*of course, I might be wrong even if i could see it.

 

[Alan123]

just found out that if i press the water constant/timed on the central heating in the kichen the ecd trips after a few mins and if i try to turn power back on with this button still on trips right away!!!!
only get the power back on if i turn water constant/timed off on heating control
but all other switches on the central heating control do not trip the electric.???? and can put power back on with them turn on??
wondering if there is a fault with the water constant/timed button?????
can this happen and if so could i just replace the central heating control ie:the switchmaster 805 control in the kitchen
also noticed that the central heating is not working
bleed the radiators but still not heating up!!! (not that i need them yet but still)
cheers Alan
come on England

 

[Lectrician]

Sounds like the boiler now.

I don't think you are going to be able to sort this yourself. You would have by now.

Get yourself a spark in.

 

[Adam_151]

But would a spark be able to diaganose where an earth fault is in a boiler and be able to fix it? I (like JohnD) would be more inclined to call out a heating engineer.

Though a spark would probably get the problem solved, probably involve moving the CH to the non RCD side of the board though

 

[Alan123]

i dont know what the prob is even if i turn the mcb of on the water heater.
the rcd still trips out so i guess boiler prob
will get someone in to take a look
cheers for all your help and advise
Alan

 

[kai]

I note you have type C6 breakers on your Lights.
Not very common to see type C's in household installs, type B's are the norm...

 

[Lectrician]

I would be to find the fault in a boiler

 

[Alan123]

where would i start looking to find the fault with bioler???

 

[Pensdown]

where would i start looking to find the fault with bioler???

That’s a very good question. I can assure you, while you’re making the tea he/she will be asking themselves the same question.

But if he/she is any good, by process of elimination they will find the fault.

Just one more thing, if I were you, I would call in a sparks because most of them know there way around a boiler. If the faults not there a sparks would have more chance of finding it elsewhere than a plumber

 

[Alan123]

sorry to keep going on with this but
been messing around with the mcb's on the fuse box and found that
if i put water on ch control in the kitchen power goes off within few mins
so i turned off all mcb's befrore i put power back on
and then turned them on one by one
and evey time i turned on the kitchen sockets mcb
power went off striaght away so problem could be in the kitchen right?????
will try unplugging washer dryer and fridge tomorrow hopefully find out more!!
Alan