What makes a motor explosion proof?

[Alan Mikkelsen]

What is the difference between a TEFC motor and an explosion proof motor? Is it just how tight they are sealed?

[Don Baer]

TEFC stand for Totaly enclosed fan colled. This design is for areas that are dusty and and this type of protection is ment to keep dust out of the winding mostly for cooling purposes. Explosion proof means it is design to contain an explosion should one occur. There are differant classes of XP design depending on the environment. For purposes of finishing with solvent based product the XP motor should be rated Class 1 Div 1 and 2.

Here is the true definition of XP as designed by NFPA.

"explosion-proof apparatus": "Apparatus enclosed in a case that is capable of withstanding an explosion of a specific gas or vapor that may occur within it and of preventing the ignition of a specified gas or vapor surrounding the enclosure by sparks, flashes, or explosion of the gas or vapor within, and that operates at such an external temperature that a surrounding flammable atmosphere will not be ignited thereby."

If you would like more informatio onthe subject you can go to the EASA, UL or NFPA or this web site http://newssearch.looksmart.com/p/articles/mi_qa3726/is_199711/ai_n8780307

to learn more.