by ericmark »
Mon May 03, 2010 8:02 am
Read the power rating of shower and compare with current rating of trip.
Since one is likely in Kw and other in amps I will give you a cross reference.
6 Kw = 26.08695652 amps
6.5 Kw = 28.26086957 amps
7 Kw = 30.43478261 amps
7.5 Kw = 32.60869565 amps
8 Kw = 34.7826087 amps
8.5 Kw = 36.95652174 amps
9 Kw = 39.13043478 amps
9.5 Kw = 41.30434783 amps
10 Kw = 43.47826087 amps
10.5 Kw = 45.65217391 amps
11 Kw = 47.82608696 amps
11.5 Kw = 50 amps
In practice the trip will take a small overload for some time so a 8kw shower would work OK with 32A trip however over time the trip will likely weaken and need replacing. However a 9Kw shower would cause problems with 32A trip. The trip size is selected to match cable not shower so normally one can't up rate the trip without changing the cable so if shower and trip size don't match then it's a case of changing shower to match trip.
Sorry about decimal points I used excel to make table. Some showers are rated at 240v instead of 230v which can make 1 to 2 amp difference so a change in local voltage could mean the difference between working and not working if already overloaded. i.e. local factory not running at weekend.