- This topic has 5 replies, 2 voices, and was last updated 5 years, 11 months ago by
.
-
Posts
-
My Neff double oven is tripping the MCB on the mains.
This occurs when I switch on any function of the top oven. The model is U1744N. The top oven has a double element at the top (grill and oven) with a second element under the casing at the bottom of the top oven. The bottom oven is fan and has multiple elements, but this is all working correctly and can be used without problem.
I have taken out the oven and removed the rear casing (after disconnection). The element connection points and all aspects of the wiring look undamaged with no signs of arcing. I have removed the top element and visually, it looks ok – there appears to be no physical damage. Testing the two separate circuits of this element with a multimeter shows resistance of over 40 . I tested the second element of the top oven without removing it by taking off the clips and testing resistance, this also showed over 40.
However, I’m still having the issue of the MCB tripping. It first happened a few weeks ago and having left it for a few days, I tested it again and it worked without issue. It is now happening all of the time. It’s not the end of the world as we still have the bottom oven, but I’d like to try and repair it.
Can anyone please suggest other steps to try, or should I assume one or both of the elements are faulty and swap them out?
I hadn’t tested that, so just tried. The oven and grill both worked without tripping the circuit. Very frustrating intermittent fault!
its one of the elements with an earth fault
if it only trips when you set the oven setting on the small oven but does not trip on the grill then its likley to be the lower element
what you have is an earth fault on the element. measuring the element is of no use what we need is an insulation value from one of the terminals to earth. you can sometimes read it on the high scales with a multi meter but an insulation tester use 500v
the trip measures current in and out of your house, thats the total current in use at one time. If just you oven was on the element draws just over 4 amps. so it measures 4A entering and measures 4A leaving then happy days. If it measures these currents and there is 0.3A less coming out than going in it will trip
the problem you have to understand is its not just your cooker thats being measured. lets say your cooker has a leakage of 0.2 amps. On its own it cant trip but if you have another appliance that has a leakage of 0.11 then together it will trip
Dave
If it was an earth leakage problem, would it not trip the RCD first? I’m learning as I go here, so apologies if I’ve misunderstood how an RCD works!
Right, just realised I’ve got all this backwards. The RCD is the thing that’s tripping, not the MCB. Completely misread what the board said. What a dummy!
So, the couple of times the oven has tripped the RCD, there was a chance the washing machine was on at the same time; today when I switched it on, it wasn’t. Maybe a combination of the washing machine (10years old, with a lot of use) and the oven at the same time, is providing enough leakage to trip. I will test again first thing tomorrow (when everyone isn’t using the internet!)
- You must be logged in to reply to this topic.