Overload protection for 120V motor

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PhaseShift

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I am wondering weather or not a small 120V motor requires overload protection. The motor has a FLA of 6A, and is fed from a 20A breaker in a panel. This motor may be operated by a pressure switch which turns the motor on and off.

My question is weather or not the motor requires overload protection? I know most likely the motor will not be run from a starter, so for these small motors does there have to be some internal temperature switch or something that turns the motor off in the event of an overload? I wouldn't think that the 20A breaker would protect a 6A motor from an overload.

Does the motor have to have an internal OL detection with way to cut off motor if fed directly from a breaker?

The contractor also used the motor terminal box as a junction point and tapped off the 120V motor feed to feed other 120V devices in the area. Is it legal to tap off the motor terminal box in this situation?
 
Take a look at 430.32(B)..there are a few options, but 1 HP or less automatically started normally requires overload protection. Often it's internal.
 
PhaseShift said:
The contractor also used the motor terminal box as a junction point and tapped off the 120V motor feed to feed other 120V devices in the area. Is it legal to tap off the motor terminal box in this situation?
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I think you are asking whether or not you can feed other loads with the motor load. [20A branch circuit].

Check out 450.53 'One or more motors and other loads...'; the answer is yes if the 3 conditions are met.
 
Most small 120V motors have internal thermal protection, usually in the form of what is commonly called a "Kilxon", which is a little thermally activated snap switch embedded in the motor body. If it has one, the motor nameplate is supposed to say so, they use words such as "Thermally Protected", "Self Protected" etc. etc. There are also a type of small motors referred to as "Impedance Protected" which simply means you can lock the rotor and they will not burn up; they can stay in a stalled state continuously. These are usually light duty appliances that use Shaded Pole motors or Universal AC/DC motors.

6A is not that small, it probably is a cap start or a PSC motor and has internal thermal protection. But if the nameplate doesn't say it is, you must assume it is not and add an OL relay or use a manual motor starter that has a built-in OL.
 
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