That is correct, Wateringress. The coil in my photo is on the left side, hidden under the sheet metal fin.
I'm not sure about the whole EU, but all breakers in Germany, since many decades, have these two working mechanisms. The bimetal strip to act time-delayed in overload condition, and the coil for instant trip in short circuit situations. There's different trip curves but the most common curve is "B" where the instant trip will start working at 3 to 5 times the nominal current.
With the most common breaker for regular outlets being B 16 Amp, the fault loop impedance must be low enough to have at very least 80 Amp flow in case of a short, to trigger the instant trip. This is also something the contractor needs to prove by measurement with a special meter.
A common value for the available short circuit current in a regular panel of a German appartment is around 300-2000 Amp. Depending on the distance to the transformer and wiring. So if the wire from the breaker to the outlet is not too long, and terminations are good, you easily make the 80 Amp plus some functional reserve.
Last edited by andey; 06/23/20 06:49 AM.
