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We have a Tecnik TKC5525/1 s/s (HB7TI01GB/01) double fan oven which is implicated in RCD trips. Sometimes other devices trip the RCD while the fan oven is on (kettle, milling machine – both probably eliminated by replacement of kettle and large 1ph motor with a smaller 3ph inverter/motor) and sometimes it is the act of turning on the fan oven which causes the trip.
The RCD is fine (trips on spec) and we suspect that perhaps the oven is leaking, but not enough to trip the RCD until something else like the kettle etc is put on load.
I am about to pull the oven out and inspect the (Moben) installation and replace the fan oven element, but before I do, does anyone have a pointer or two that might guide my investigation or replacement. The ven has been in place about 20 months.
Re: Tecnik Double Fan Oven: Intermittent Earth Leakage Trip
the problem with RCD’s is it is cumulative
ie it takes 30mA to trip an RCD. if you oven leak 20 then it wont trip till other things add up to over 30.
the oven element is the most likely. to be sure you either have to change it or get an electrician to megger test it for eart leakage. dont forget you have more than 1 element in the cooker and 1 or all could be faulty you just have to find which one
Dave
Re: Tecnik Double Fan Oven: Intermittent Earth Leakage Trip
the problem with RCD’s is it is cumulative
ie it takes 30mA to trip an RCD. if you oven leak 20 then it wont trip till other things add up to over 30.
the oven element is the most likely. to be sure you either have to change it or get an electrician to megger test it for eart leakage. dont forget you have more than 1 element in the cooker and 1 or all could be faulty you just have to find which one
Dave
Re: Tecnik Double Fan Oven: Intermittent Earth Leakage Trip
I notice in your posting that you have a milling machine and a controlling invertor. Often motors and invertors can generate harmonics & odd spikes causing RCDs to trip. You might want to look at this and eliminate the motors & invertor first.
As mentioned, it is almost certain that you have a cumalative effect.
Further, I have had a number of defective Main RCD Switches of recent times. What make of RCD is it?
You mention that you tested the RCD. Was this for trip times or trip current?
Regards
Re: Tecnik Double Fan Oven: Intermittent Earth Leakage Trip
RCD is on spec for both trip time and current – tested by a qualified electrician. Still get the same cumulative combination – wee woman turns on oven to heat a bun then kettle for coffee and if I am in the workshop with lathe/mill on (running or not) then darkness. I’ve run the lathe (Jaguar CUB inverter) and mill (1.5Hp single phase!!) for several years without issue until about 8-10 months after kitchen install and new bathroom lights installed by said sparky. Mill is now on a Mitsubishi inverter – both inverters are fitted with RFI filters. The only new elements in this saga are (or were) kettle – replaced and Tekniks fan oven, so I’m now going to drag it out, inspect wiring and replace the fan oven element. Other household items include several switch-mode PSU’s which are also known for leakage. Sparky had a notion to split off the workshop supply before the RCD – it’s on a separate consumer unit – and add an RCD there, thus avoiding an RCD race – but that would mean ripping out part of the kitchen….
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