disconnect method for motor in Class I Div 1

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sailboat

Member
I want to install a 3 ph motor (32.2 amp 208 VAC) located in a Class I Divison 1 area. It's feeder will come from a control panel that will be in a different (unclassified) area and will be protected by 50 amp fuses.

Can I use a Class I Div 1 rated switch (120 VAC) located next to the motor in the Class I Div 1 room to operate the coil of a contactor (rated 50 amps) located in the control panel to disconnect power to the motor?

Would this arrangement be a permitted option instead of installing a 50 amp 3 ph Class I Div 1 disconnect in the room next to the motor?

I'm looking at Artical 501.6 for info but this situation doesn't appear to be addressed. What other code section deals with this issue?
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
Re: disconnect method for motor in Class I Div 1

What is the purpose of the disconnect? You cannot use a contactor for lockout tagout. 430.102(B) may require a disconnect switch at the motor.
Don
 

sailboat

Member
Re: disconnect method for motor in Class I Div 1

The purpose of the disconnect would be to work on the motor. The lockout could be done at the switch located next to the motor that operates the coil on the contactor
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
Re: disconnect method for motor in Class I Div 1

A lockout switch must lockout the power to the equipment. Locking a switch on a control cirucit is not the same. You must lockout the power to the motor itself.
Don
 

friebel

Senior Member
Location
Pennsville, N.J.
Re: disconnect method for motor in Class I Div 1

To: sailboat, In order to do this properly, you must have a start/stop pushbutton, meeting 1-1-D Classification. The area of Class 1-1-D will extend so many feet, possibly 10, 15 or 25 feet.Then you have an area of Class 1-2-D for so many feet. Then you will have an area where you could have a General-Purpose four-pole disconnect switch, fused or unfused, that would open the motor legs, T1,T2, and T3. Also it will open the 120-volt control circuit feed for the control circuit.
This is one way, or you could install an Class
1-1-D disconnect switch at the motor location.
The choice is yours. But you need to do it safely, and by code.
 

pwhite

Senior Member
Re: disconnect method for motor in Class I Div 1

i believe hubbell makes an explosion proof disconnect that should meet your needs.
 
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