I presume you are aware of this nice solution to take a normal relay, get the right base and one can turn it into a timer… Well, one day I get a call:
Hi guys, How many people know how to reset a circuit breaker? Just push it up you say.
Would you believe a circuit breaker does not always trip at the same tripping point! There are various reasons a circuit breaker tripping point deviates…one is temperature. Well for some more then others – the thermal-based ones have big deviation, it even gets affected by the neighbors.(grouping) as well as the frequency of the supply. […]
It is Saturday night and you are having a grand party…the powerful sound system is tuning out the music…pulling heavy amps. There comes the drunk uncle…he trips over the self-made extension cord and there the lights go out…
It is a test button to confirm the operation of the earth leakage… “Duhuh (or something that sounds like that)” he says…I can see that…it is written on the unit…I ask what does it do. Does it push a lever inside and trip the unit mechanically or does it test it electrically as well…what does it […]
When we have an electrical storm the earth leakage trips and in my assessments it always does when some serious lightning energy is behind it.
Ahh, but they do exist…3pole earth leakages with no neutral. Then where will one use such a thing? But it gets worse:- Why would ‘Hager have a 3pole earth leakage device BD364, BF364, BDC364, BTC364 – I can’t use these for motors and the like, they will trip for nothing, or will they? So where […]
One day an electrician calls me saying the earth leakages he bought is “over sensitive” I bought this new digital tester and they all trip around 22mA. So I say: You do realize that ELD /RCD are subject to temperature variations, so on a hot day we still want to be sure it trips nothing […]
I actually had a call from Schneider technical to assist in selecting a downstream protection sub board circuit breaker. They mentioned a suggestion to put fuses in the board. *This off course the solution to lift the kA rating for the down stream designed equipment. I could not help but to smile and confirm Schneider […]
Mmmm…So we got this feedback from a fuse supplier suggesting we use 2x400A fuses in parallel to make up 800Amp. Why is there something that bugs me about this? And since we are at this…What about using contactors in parallel to qualify for a higher current load? Maybe it just sound wrong theoretically but in practice […]


