Compressor mag starter question

[dmaxfireman]

I am putting together a Frankenstein compressor with a Leeson 5hp (20.8FLA) single phase motor. The motor has a thermal overload reset on it. Read plenty of threads recommending a mag starter over only running a pressure switch.

Can I mount a 2 pole contactor in a junction box and have it function the same as a magnetic motor starter? Idea would be 1/3 - 1/2 the cost of a mag starter.

Is there any reason to go with a 120v vs 240v coil?

 

[Norcal]

I am putting together a Frankenstein compressor with a Leeson 5hp (20.8FLA) single phase motor. The motor has a thermal overload reset on it. Read plenty of threads recommending a mag starter over only running a pressure switch.

Can I mount a 2 pole contactor in a junction box and have it function the same as a magnetic motor starter? Idea would be 1/3 - 1/2 the cost of a mag starter.

Is there any reason to go with a 120v vs 240v coil?

Is the motor supplied with factory overload protection? If yes then a contactor would be OK, if not then a magnetic starter should be used, a contactor that is UL recognized, is not kosher to use though, it needs to be listed by a NTRL, Nationally Recognized Testing Laboratory such as UL, CSA, or ETL, to name a few. a 240V coil means a neutral or control transformer will not be needed like it would with a 120V coil.

 

[wyliesdiesels]

Is the motor supplied with factory overload protection? If yes then a contactor would be OK, if not then a magnetic starter should be used, a contactor that is UL recognized, is not kosher to use though, it needs to be listed by a NTRL, Nationally Recognized Testing Laboratory such as UL, CSA, or ETL, to name a few. a 240V coil means a neutral or control transformer will not be needed like it would with a 120V coil.

second sentence says motor has a thermal overload reset on it

 

[dmaxfireman]

Is the motor supplied with factory overload protection? If yes then a contactor would be OK, if not then a magnetic starter should be used, a contactor that is UL recognized, is not kosher to use though, it needs to be listed by a NTRL, Nationally Recognized Testing Laboratory such as UL, CSA, or ETL, to name a few. a 240V coil means a neutral or control transformer will not be needed like it would with a 120V coil.

Doesn't UL fall under NRTL? Why wouldn't a UL listed contactor be acceptable?

 

[Norcal]

Doesn't UL fall under NRTL? Why wouldn't a UL listed contactor be acceptable?

I said a UL Recognized contactor they are a recognized component of UL listed equipment and can be used replace one on listed equipment but unless want to pay to have it listed by a NTRL, better to buy a listed contactor, one will have a UL logo and the other will have a U with a backwards R on it. They are not the same.

 

[dmaxfireman]

Thanks very much for clarifying.

 

[wyliesdiesels]

Doesn't UL fall under NRTL? Why wouldn't a UL listed contactor be acceptable?

recognized vs. listed. there IS a difference