NEMA 4X tefc motor in a class 1 div 1 and div 2 location

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rbalex

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Mission Viejo, CA
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Professional Electrical Engineer
is this allowed at all?
They are common in Class I, Division 2 and there are protection techniques that would permit them in Class I, Division 1. We would need lots of details to determine if a specific application is suitable.
 

rbalex

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Location
Mission Viejo, CA
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Professional Electrical Engineer
Is there even such a thing as a NEMA4X TEFC motor?

Maybe a UL type 4X TEFC motor. Not even sure that exists.
NEMA MG-1 doesn't recognize "Type 4X" enclosures as it applies to motors; however, virtually all NEMA "Totally Enclosed" motor types would meet 4X requirements and I understood what rey-man meant. Most explosionproof motors are basically modified TEFC or TENV. UL lists explosionproof motors for Division 1 and a few (VERY few) motors for specific Division 2 applications. No motors are listed for "ordinary locations."

Many "ordinary location" motors are acceptable "as is" in Class I, Division 2. See the last sentence in 501.125 (B): "... In Class I, Division 2 locations, the installation of open or nonexplosionproof enclosed motors, such as squirrel-cage induction motors without brushes, switching mechanisms, or similar arc-producing devices that are not identified for use in a Class I, Division 2 location, shall be permitted."
 

rey-man

Senior Member
Location
New york
They are common in Class I, Division 2 and there are protection techniques that would permit them in Class I, Division 1. We would need lots of details to determine if a specific application is suitable.

what sort of details should i look for? ...to determine if it is suitable to Class 1 div1 location.

the nameplate does not even tell the "T" rating of the motor.

as always, thanks for your responses.
 

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
what sort of details should i look for? ...to determine if it is suitable to Class 1 div1 location.

the nameplate does not even tell the "T" rating of the motor.

as always, thanks for your responses.

If it is suitable for use in a division 1 area it will say so on the nameplate.
 

rey-man

Senior Member
Location
New york
in a cls 1 div 1 area, if the motor needs to connect to a toggle switch, do you need to put a seal 18" from within the motor and the switch, if the run is more than 3 ft?

is there such a thing that at certain HP ratings, seals are not required?

thanks again.
 
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