acensor wrote:Also, I'm a bit confused with your suggestion that there should be a 25 amp breaker at the service box on the 240 line. In my circuit/service panel there are three 240v DUAL breakers (one for the electrical oven, one for the air conditioner, and one for the unused electric clothes dryer wall plug.
Each is a DUAL (pair of breakers) each with a total capacity of 50 amps.
The one for the oven is properly sized - I'm sure that one has a 6 gauge wire feeding a socket rated at 50 amps
I'm not so sure about Europe, but here in the USA we don't have either dryer or air conditioning outlets rated for 50 amps. If you'll check the markings on the outlets and the size of the wire feeding them, I would bet neither of those circuits should have 50 amp breakers
Doesn't make much sense to me that device you plug in dictates what breaker is back at the box (that's dictated by what the wiring FROM the box is rated for -- not so?).
What am I missing here?
If you want to plug in an EVSE (or any other device) rated at 20 amps into any of those 50 amp circuits, do you think the wire from the plug to the EVSE is the same size as the wire from the socket to the power panel? Nope
The circuit breaker should never be sized larger than the capacity of the wire on the appliance you're feeding, otherwise it could be possible to melt or burn that lighter gauge wire in the event of a short circuit before your huge breaker will trip. If your EVSE is rated for 20 amps, it probably has a 10 or 12 gauge wire attached to it's plug and you cannot use a 50 amp breaker to feed a 10 or 12 gauge wire. If you intend to use that outlet only for the EVSE, you really should replace your breaker with the smaller 25 amp
Now, if your EVSE has it's own 20 or 25 amp fuses, then plugging it into a circuit rated for 50 amps is not so problematic, though if it was to be permanently mounted, I'm pretty sure the code would still require the smaller breaker