Jack:
You are struggliing to get the info out of NFPA 497 becuase its the wrong code. What you are looking for is in NFPA 70 (the National Electric Code), Article 501, section 8(b). NFPA 497 is a guidance document for hazard classifications, whereas Articles 500 and 501 of NFPA 70 are specific to devices and methods. You should get the latest edition of the code, but your answer is that the motor (and wiring) probably need to be approved for Class I Div 2 locations. Check with the motor supplier. You also need to be aware of the Group under which the vapors are classified. If you have a Group A, B or C vapor (they are relatively uncommon, but include acetylene), you probably need a special motor, even if it is of explosion proof design.
... Bruce D. Bullough ...
Lead Process Engineer
Foth Production Systems, LLC
8550 Hudson Boulevard North, Suite 100
Lake Elmo, MN 55042
Direct: +651-288-8598 Fax: +651-288-8551
<a href="http://www.foth.com">http://www.foth.com</a>
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Jack Osborn <jhosborn@yahoo.com>
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01/10/2007 07:10 PM
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Re: [PipingDesign] tell me idea guys........
do you guys know much about the Class 1 Div 2 requirements? I am trying to get through NFPA 497 to understand whether a TEFC motor will work in a Class 1 Div 2 setting.....I am thinking not....that it requires a TENV motor. Reading this is like having your toenails pulled out....one by one.
Jack
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