Classes

[xformer]

Hello,
I remember learning that Class 1 was good for Class 2 locations and Class 2 was good for Class 3 locations, but I cant seem to spot that in 2020 code. Am I in error?

 

[don_resqcapt19]

Hello,
I remember learning that Class 1 was good for Class 2 locations and Class 2 was good for Class 3 locations, but I cant seem to spot that in 2020 code. Am I in error?

The temperature limits are different between Class I and Class II, because Class II has to take into account the insulating factor and long term contact of the dust on the equipment. You need to use equipment that is identified for the Class, Division and Group of the actual hazard.

Note that is not to say that there is not equipment identified for multiple classes. Just sayin that you can't say that you can always use Class I equipment in a Class II location. You can only do that where the equipment is identified for use in both classes.