satori
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- Reaction score
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Parents in law are experiencing and intermittent fault. Occasionally, when one of the rings on the hob (I think the hob is of the induction type) is turned off, both the hob MCB and the associated RCD trip. I can't envisage a fault that would trip both.
The property is a bungalow that had an extension added about a decade ago (the hob dates from that time). At that time the CU was replaced, for diversity the circuits were divided between two RCDs. The hob and oven (an MCB each) and all the sockets[1] are on one RCD; the other RCD has all the lighting and the immersion heater.
I'm intending to borrow a tester from work and pay a visit, but I'd like to go with a better idea of what I should be looking for. My intention, before suggestions from the wise here, are as follows:
* Safe isolation!
* Take a look inside the CU and check all connections.
* Check connections in the isolator local to the hob.
* Check continuity on R1, R2, and Rn of all circuits associated with that RCD.
* IR test the circuits associated with that RCD (with the hob circuit I intend to do so with the isolator off, then on - are there likely any sensitive electronics in an induction hob that won't like a 500V IR test?).
I'm a bit concerned about having to pull the kitchen apart to get at wiring for the hob if I find there is a fault down-stream of the isolator.
How does the above sound to you? I'm going to have a chat with the guys at work on Monday, but we're mainly industrial, and I'd like a broader experience than my colleagues can offer!
Thank you for any suggestions on a better way to proceed.
[1] I don't yet know if the sockets are on RFC or radial. It being an old bungalow with an extension, I'm worried the builder may have the extension as a spur, but this is relatively ancient history, no one would remember. I can only hope he did the right thing - I don't know if the in-laws even remember who did the work.
The property is a bungalow that had an extension added about a decade ago (the hob dates from that time). At that time the CU was replaced, for diversity the circuits were divided between two RCDs. The hob and oven (an MCB each) and all the sockets[1] are on one RCD; the other RCD has all the lighting and the immersion heater.
I'm intending to borrow a tester from work and pay a visit, but I'd like to go with a better idea of what I should be looking for. My intention, before suggestions from the wise here, are as follows:
* Safe isolation!
* Take a look inside the CU and check all connections.
* Check connections in the isolator local to the hob.
* Check continuity on R1, R2, and Rn of all circuits associated with that RCD.
* IR test the circuits associated with that RCD (with the hob circuit I intend to do so with the isolator off, then on - are there likely any sensitive electronics in an induction hob that won't like a 500V IR test?).
I'm a bit concerned about having to pull the kitchen apart to get at wiring for the hob if I find there is a fault down-stream of the isolator.
How does the above sound to you? I'm going to have a chat with the guys at work on Monday, but we're mainly industrial, and I'd like a broader experience than my colleagues can offer!
Thank you for any suggestions on a better way to proceed.
[1] I don't yet know if the sockets are on RFC or radial. It being an old bungalow with an extension, I'm worried the builder may have the extension as a spur, but this is relatively ancient history, no one would remember. I can only hope he did the right thing - I don't know if the in-laws even remember who did the work.
