3ph motor overload

[jmtisme]

I want to fit a stand alone 3ph overload to a 5.5kw motor its wired in delta (guess that doesn't matter) can anyone tell me what size of overload I should be fitting. I have been advised to fit a variable set at 13A mark. I think thats quite low any comments will be appreciated.

 

[Guest123]

At 0.8 PF, 5.5KW is only 10 odd amps per phase, the old rule of thumb for overloads used to be FLC x 110% but overloads for new motors can be set at FLC really.

 

[Knobhead]

You say a stand alone O/L, is this to act as the O/L’s for the motor or as an alarm? If an alarm 95-100%

 

[pmac10]

actually it does matter if its wired in star or delta, does it have a nameplate? if it does set to the value for delta printed on this (it will pull more in delta). the overload will not trip at this value but will run above this for a short period before operating

 

[jmtisme]

Cheers guys