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Hi Mike,
If EvilBaying you want either a 4-pole or 3-pole-with-NO-aux (may be listed as "3NO+NO" or similar), and it must be rated for the motor - motors are the "AC3" rating in kw or hp marked on the contactor - this will be the LOWEST marked as motors/transformers are inductive and Hard Work, generating high voltages when the load current' S interrupted with bigger arcs at the contacts...
If you want to be extra safe, 24v control circuits can't fry you, you'll need a 24v a.c. coil contactor and a 208-24v control transformer rated about 50 va - and as suggested, a motor overload that sits between motor and the contactor, either fixed for your motor's full load amps or with an adjustment covering that current - the setting is such that it'll run at FLA but trip 20 - 30% above, saving the motor.
Check the motor voltage is right for your supply or it can be wired for it, and if it's never run in your sight check it for opens, leakage to earth etc!
Dave H. (the other one)
If EvilBaying you want either a 4-pole or 3-pole-with-NO-aux (may be listed as "3NO+NO" or similar), and it must be rated for the motor - motors are the "AC3" rating in kw or hp marked on the contactor - this will be the LOWEST marked as motors/transformers are inductive and Hard Work, generating high voltages when the load current' S interrupted with bigger arcs at the contacts...
If you want to be extra safe, 24v control circuits can't fry you, you'll need a 24v a.c. coil contactor and a 208-24v control transformer rated about 50 va - and as suggested, a motor overload that sits between motor and the contactor, either fixed for your motor's full load amps or with an adjustment covering that current - the setting is such that it'll run at FLA but trip 20 - 30% above, saving the motor.
Check the motor voltage is right for your supply or it can be wired for it, and if it's never run in your sight check it for opens, leakage to earth etc!
Dave H. (the other one)