When cleaning my ceramic hob yesterday (wet, but not excessively), I noticed some voltage going through my wet finger when touching the shaft of one of the knobs (I had removed the knobs before). I immediately stopped the work and used the circuit breaker. (And that is what you should do, too, if feeling even the most gently voltage. Really)
- The knobs are mounted right above on the hob, where it does get wet sometimes
- The hob was installed by a professional electrician, but it is an old one.
- The casing is connected to protective earth, but the knob shaft isn't (measured when the circuit breaker was open)
I cannot measure any voltage on the knob shaft, presumably because it has had enough time to dry. But I am wondering: Isn't it supposed to be connected to protective earth, just like the casing?
Because the plastic knob will not always provide good isolation: it's easily detachable, and even when attached, the 1/2 " it provides as a distance from the shaft sometimes gets really wet when cooking.
Should I replace the whole hob?
Best Answer
You say the hob is old so I would get an estimate to replace all 4 or 5 controls (the others may not be too far behind the one in question in wear and tear) along with an assessment of the hob's overall condition and compare that against buying a new one.
My Mom has a ceramic cooktop and I'm going to take a meter with me when I see her later today. Now I'm curious.