Fractional HP motor & a code question 1

[toygasm4u]

I have a 1/20 HP motor on a reducer, 115V. I want to plug this into the wall. The motor doesn't include any sort of thermal protection / OL protection. For 1/20 HP, am I required to provide additional protection aside from the 15A branch circuit protection i.e. circuit breaker?

I keep getting caught in the loop created by NEC 2008 430.42(C), 430.32, and 430.53. A code wizard I am not.. but I can't help but think about a simple box fan. These don't have thermals that I'm aware of.

 

[toygasm4u]

It's actually a dual voltage PSC motor.. .I don't think it makes a difference, but I figured I'd better add that in there.

 

[Compositepro]

Actually, all the cheap,little 115 volt fans I've examined (not many) have had thermal fuses in the windings.

 

[jraef]

Most likely it has a "Klixon" thermal switch built-in somewhere. It may or may not have an external reset, some are automatic when it cools, but it would say somewhere that it is "Thermally Protected" or has "Integral Protection", something like that.

http://www.sensata.com/support/klixon-motor.htm

But beware! Dayton (a common brand sold by Grainger) for some reason apparently sells a PSC gearmotor that has NO thermal protection built in, which means you would have to supply it externally in the form of an OL relay. No idea why they would do that, cheap I guess.

http://www.electricmotorwarehouse.com/Dayton/6Z073.htm

If you are going to control it manually with a switch, but a Manual Motor Starter what has a 1 pole heater element, sized for the FLC of that motor (looks like .62A from that Dayton sheet).

(Note: image is from eBay, will eventually disappear)

Box fans and the like often use "impedance protected" motors, a euphemism for it being a shaded pole motor that can be held at locked rotor and not overload. As a "fail safe" issue, they typically have a small wire buried somewhere in the design that will open long before anything else catches fire. They will not identify it as a fuse however, because that would imply it can be replaced, and it cannot.




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[toygasm4u]

Thanks for the feedback guys; I think a thermal is an option we can ask for from the manufacturer (cheaper that way). Waiting for feedback from them now.