Thermistor protection req'd in Class II Div II Group F or G ? 1

[bklauba]

Do electric motors to be used in a Class II Div II Group F or G environment require more than mere short circuit and overload protection, i.e., do they require thermistor protection also?

 

[elinBG]

I dont think that it is officialy regulated what kind of protection you should use for ex-danger areas.

However if you decide to use PTC-thermistors, overload protection and i.e.they should be EX-certified.
Here in Bulgaria we have a Ex-proof PTC-thermistor (they are VERY MUCH MORE expensive than the standard ones).

Greetings

 

[dpc]

See NEC Article 502.125. In general, for Division I, Class 2 locations, TEFC motors can be used, but maximum temperature must comply with limits in Article 500.8. I don't believe temperature monitoring is required, unless things have changed in the last few years.

But since you couldn't be bothered to tell us where you are located, it's hard to say for sure.

 

[ScottyUK]

In the IEC world, converter-fed motors (e.g. variable speed drives), may need stator RTDs when used in hazardous areas. I'm not sure if there's a similar requirement under the North American area classification system.

 

[bklauba]

Thanks to all for replies, and sorry for not stating location, which is USA.

 

[DRWeig]

bklauba,

I've never run into any requirement for motor temperature monitoring in hazardous locations.

Best to you,

Goober Dave

Haven't see the forum policies? Do so now: Forum Policies

 

[DRWeig]

Forgot to mention -- USA

Best to you,

Goober Dave

Haven't see the forum policies? Do so now: Forum Policies