redmondjp
Well-known member
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If I read this correctly, this starter is rated for 40fla, at 240volt single phase 7.5hp. So this means I can use this starter?
Yes, that's a great starter and it's big enough for your motor. You just need to make sure that the overload heater strips (the vertical pieces of metal between the screw terminals at the bottom of the box) are selected to match your motor, in order to provide the proper protection.
The way those heater strips work is that they are supposed to heat up at the same rate as the motor windings, so if the motor gets too hot, so do those strips, which then expand, causing them to bend in the middle and trip off the contactor.
For a single-phase motor, you only need one heater strip (with a jumper on the other current-carrying pole, with the third pole not used), but there is no harm in using two heater strips.
Each motor starter manufacturer has a table (search online) showing the heater strip part numbers and what motor HP or full load amps correspond to each part number.
The other thing to check is the contactor coil voltage in the starter. Hopefully it's 208-230V (120V also OK but you have to then run a neutral wire into the starter). If 277V or 460-480V, then you'll have to change out the contactor coil.









