Main Trip Switch Tripped, All Power lost, electric cooker element.

[ban-all-sheds]

Sigh.

What you say about knowing things is quite true. But when you wrote this:

Why isn't there a separate Mcb named OVEN so that when an element goes it's only the oven switch that is tripped?

You had been told repeatedly that RCDs trip for different reasons than MCBs, and that your RCD covers all of your circuits.

 

[Steven Prentice]

Oven / fridge switch. Sounds like it has been wired incorrectly, that the live and neutral are on opposite sides of the switch. A simple fix for the landlords electrician but for you a minor inconvenience

What supplies the cooker.. turn your computer off first... then go through the consumer unit and turn off and on each circuit in turn until the cooker turns off.. thats where your cooker circuit is.

MCB and RCDs do different jobs
MCB (miniature circuit breaker) detects and trips on a high current, a short circuit perhaps betwen live and neutral and is there to protect your equipmnt
RCD (residual current device) detects if there is an earth fault where the current goes to earth and not back via the neutral. These are there to protect you.

 

[ban-all-sheds]

Oven / fridge switch. Sounds like it has been wired incorrectly, that the live and neutral are on opposite sides of the switch.

¿Que?

 

[mfarrow]

¿Que?

He means the supply has been connected to the LOAD side of the cooker switch, which means the feed to the fridge is going through the cooker switch as well as the socket switch.

 

[ban-all-sheds]

Ah.

What a truly mad way to express that.

Roger Federer and Andy Murray are on opposite sides of the net.
The library and the post office are on opposite sides of the High Street.
Live and neutral are on opposite sides of the switch.

 

[DrWho]

Steven Prentice

So if the wiring was connected correctly are we saying that when the element blew only the Mcb would have gone so that all power apart from the oven would have stayed on?

 

[ban-all-sheds]

No, nobody is saying that, except you, despite the number of times you've been told that RCDs and MCBs do different things, and you only have one of the former.

 

[DrWho]

So then you are saying that it's normal for the RCD to trip when an element goes faulty? even after Steven Prentice has said it has been wired incorrectly.

 

[DrWho]

For goodness sake, all I'm trying to know is it normal for the whole power to be cut off with the Rcd tripping when an element decided to go wrong?

 

[bernardgreen]

For goodness sake, all I'm trying to know is it normal for the whole power to be cut off with the Rcd tripping when an element decided to go wrong?

When the supply to all the MCBs and hence to all the circuits ( lights sockets appliances etc etc ) is via the single RCD then if anything trips that RCD then all circuits will be without supply

 

[ban-all-sheds]

For goodness sake, all I'm trying to know is it normal for the whole power to be cut off with the Rcd tripping when an element decided to go wrong?

When elements fail they can sometimes short to earth, though usually more common with water heating elements, this can often trip an earth trip like you have, the mcb works different, so its common for an Rcd to go off but the Mcb stay on.

The RCD on your consumer unit protects ALL the circuits ,so in the event of an earth leakage fault ( as can happen when oven element failed ) it cuts power to ALL circuits. It can therefore also be used as a " main " on / off switch. The individual mcb's provide a different type of protection ,against over current . and each MCB only protects the circuit it is connected to. Hope this helps

The RCD tripped ,as it should , when oven fault occurred. That's why its there. Is this oven your own ,or landlord provided ?

No the RCD tripped because of an earth leakage . if there was an over current that would trip the MCB and it wouldn't trip the rcd. As said earlier the RCD and MCB re act to DIFFERENT faults.

With the consumer unit you have ,RCD will cut power to ALL circuits if an earth leakage fault occurs on ANY circuit. Very sensitive device and there to protect you.

 

[EFLImpudence]

For goodness sake, all I'm trying to know is it normal for the whole power to be cut off with the Rcd tripping when an element decided to go wrong?

YES

 

[SimonH2]

Here's something else that's weird, what you see here is red wall switches in the kitchen with one plug attached, the one on the left says COOKER underneath it and is on the on position, the switch to the right next to the grey plug says SOCKET underneath, this too is on. if I switch any of these off the fridge turns off, how crazy is that? image supplied.

OK, what you have there is a cooker switch which according to the descriptions given is supplied from it's own MCB - labelled COOKER. For whatever reason, it's not being used to supply a cooker - and only has the fridge plugged into it, presumably because it's a conveniently located socket to use.
As previously mentioned, someone has connected the supply to the load side of the cooker switch - hence why both have to be on for the fridge to run. It's not right, but it's not dangerous - it just suggests "sloppy" workmanship on the part of someone who's worked on it.

It does seem odd not to use the cooker circuit for the hob - these are high current devices, and while induction hobs can be set to run off a 13A supply, it's far from ideal. Most likely, this and the oven are both plugged into the socket ring circuit. Having said that, it was probably done by a kitchen fitter - of the sort who doesn't know enough to know that he's dangerous

When I reported the fault I was told that the electrics had passed all their safety checks, I doubt this very much.

If in doubt, ask to see a copy of the last EICR (Electrical Installation Condition Report) - if it has genuinely passed electrical tests then they'll be able to show you a copy, if they don't have one then be suspicious.

 

[EFLImpudence]

Have we been told that the cooker switch does not control the hob?

I have an engineer coming tomorrow to replace the element, should he be able to test and check the trip switch at the same time, in other words will he be classed as a qualified electrician?

That was Friday. What did he do and say?

 

[DrWho]

He replaced the faulty element and that was it.