Oven trip new replacement RCB when being switched off.

[RCD Issue]

I'm having my house re-wired and have an RCB trip issue with the oven. The oven works fine and does not trip while in use, and never tripped the previous RCB, which has now been replaced.

It's a Bosch oven controlled by a rotary switch. When you are turning the oven off, turn the switch anti-clockwise, (Straight from "oven" to "off") the new RCB trips. If you rotate the switch clockwise, through all the other settings (grill, fan, etc.) to the off position, the RCB does not trip.

The electrician says this is a fault with the oven. I have told then the oven never trip the previous RCB when being switched off, but they still say its an oven fault.

So the question is - Is this an oven fault that was previously undetected by the older RCB, or is it related to the new RCB or the new wires to the oven?

TIA

 

[SPECIAL LOCATION]

RCB??? I assume you mean RCD..

An RCD tester can be used to verify an RCD is operating correctly, (ie Not over sensitive and not too slowly), by following the guidance of BS7671 wiring regulations.

Any wiring can be tested by using continuity and insulation resistance tests to again verify compliance with BS7671..

If both of these have been done it would suggest it is not the RCD or the cables at fault..

BUT..
you do not say if the oven RCD also supplies other circuits?
In which case it could be multiple devices together causing the trip..

But also if it is being rewired I would have expected individual RCBO's for every circuit..
NOT shared RCD's which are just a bad idea and poor design option from the start!

 

[RCD Issue]

RCB??? I assume you mean RCD..

An RCD tester can be used to verify an RCD is operating correctly, (ie Not over sensitive and not too slowly), by following the guidance of BS7671 wiring regulations.

Any wiring can be tested by using continuity and insulation resistance tests to again verify compliance with BS7671..

If both of these have been done it would suggest it is not the RCD or the cables at fault..

BUT..
you do not say if the oven RCD also supplies other circuits?
In which case it could be multiple devices together causing the trip..

But also if it is being rewired I would have expected individual RCBO's for every circuit..
NOT shared RCD's which are just a bad idea and poor design option from the start!

The oven was previously on an RCD but is now on a new RCBO. This feeds the oven switch, which also has a single socket. The socket is used for the spark on the gas hob. The hob is also an existing item.

The electrician says he has tested the RCBO and it is fine.

 

[SPECIAL LOCATION]

The electrician says he has tested the RCBO and it is fine.

Sounds like the RCBO is doing exactly what it is designed to do then?

 

[Fleeting]

Are you referring to the rotary switch on the oven and not the cooker control unit, with the socket on the wall causing it to trip.

 

[RCD Issue]

Are you referring to the rotary switch on the oven and not the cooker control unit, with the socket on the wall causing it to trip.

Yes. The oven trip the rcbo when its rotary control switch is rotated anti clockwise, direct from "oven" to "off". If rotated clockwise, through all the other settings to the off position, the rcbo is not tripped. The oven works fine when being switched on and does not trip the rcbo in use.

The oven never tripped the rcd, which it was connected to the day before, when being switched off or in normal use.

 

[binky]

it's possible the old RCD was not functioning correctly, as hardly anyone ever presses the trest button several times a year, like you are suppossed to do, then the mechanism can become 'sticky' and may not have even been working properly at all. Still unusual to trip on turning off though.

 

[Fleeting]

I suspect the rotary switch isn't clearing the circuit correctly, it could be arcing which may well trip the rcbo.

 

[Andy™]

from previous experiance... its almost guaranteed to be the oven element

 

[BorisJ]

it's possible the old RCD was not functioning correctly, as hardly anyone ever presses the trest button several times a year, like you are suppossed to do, then the mechanism can become 'sticky' and may not have even been working properly at all. Still unusual to trip on turning off though.

There are no test buttons on an RCD.

 

[BorisJ]

Yes. The oven trip the rcbo when its rotary control switch is rotated anti clockwise, direct from "oven" to "off". If rotated clockwise, through all the other settings to the off position, the rcbo is not tripped. The oven works fine when being switched on and does not trip the rcbo in use.

The oven never tripped the rcd, which it was connected to the day before, when being switched off or in normal use.

RCD and RCBO are different things. Almost certainly rotary switch problem.

 

[BorisJ]

from previous experiance... its almost guaranteed to be the oven element

Not this time as it only trips on switch off.

 

[Geoff1946]

Not this time as it only trips on switch off.

I wouldn't be so sure. Maybe a bit of leakage to start with, + transient from arcing at switch contacts, possibly its single pole switching or a time difference between poles. Wouldn't surprise me.

 

[George Lisle]

I'm having my house re-wired and have an RCB trip issue with the oven. The oven works fine and does not trip while in use, and never tripped the previous RCB, which has now been replaced.

It's a Bosch oven controlled by a rotary switch. When you are turning the oven off, turn the switch anti-clockwise, (Straight from "oven" to "off") the new RCB trips. If you rotate the switch clockwise, through all the other settings (grill, fan, etc.) to the off position, the RCB does not trip.

The electrician says this is a fault with the oven. I have told then the oven never trip the previous RCB when being switched off, but they still say its an oven fault.

So the question is - Is this an oven fault that was previously undetected by the older RCB, or is it related to the new RCB or the new wires to the oven?

TIA

I had a similar problem with an AEG oven (see earlier posts). I tested everything and could find no faults with the oven. Eventually I simply replaced the heating element and it has never tripped again. Not difficult and not expensive.

 

[SPECIAL LOCATION]

There are no test buttons on an RCD.

Oh dear!

We had better start informing various manufactures they have been building their RCD's wrong!
etc.. etc...

as per many of your posts, once again factually incorrect.

 

[Andy™]

Not this time as it only trips on switch off.

like i said, from past experience...

 

[Andy™]

There are no test buttons on an RCD.

quite simply, BS

 

[Bruspark]

There are no test buttons on an RCD.

What ??

 

[SPECIAL LOCATION]

There are no test buttons on an RCD.

What ??

quite simply, BS

Oh dear!

We had better start informing various manufactures they have been building their RCD's wrong!
View attachment 13445 View attachment 13446 etc.. etc...

as per many of your posts, once again factually incorrect.

As I said earlier I am currently composing an e-mail to inform numerous RCD manufactures they have been doing it WRONG..
sticking those buttons marked "T"
with instructions to press to "TEST"!!!

 

[Dranok]

There are no test buttons on an RCD.

RCD and RCBO are different things. Almost certainly rotary switch problem.

Who is this guy? A DIYer trying to troll us to get a reaction? This isn't YouTube! It's meant to be one of the few places intelligent people can go for serious (or at least technical) conversation without getting sidetracked by the nonsense the kids from nonprofessional sites bombard us with.
Since he obviously doesn't even know what an RCD actually is, perhaps admin should remove his posting rights...