Cord seal, Class 1 Div II

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augie47

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I have am install where cords are being used on pump motors.
The install meets the specs shown in 501.140

I have searched and can not decide if these cords require explosion proof seals at either the motor or j box end.

help.
 

rbalex

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Mission Viejo, CA
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Professional Electrical Engineer
I have am install where cords are being used on pump motors.
The install meets the specs shown in 501.140

I have searched and can not decide if these cords require explosion proof seals at either the motor or j box end.

help.
As something of a corollary to 501.140(B)(5), which states where the cords must be sealed, other cases in Division 2 are not required to be sealed. Basically, you can treat a cord that is otherwise acceptable under 501.140 as a multiconductor cable installed per 501.15(E) in general, and probably 501.15(E)(3) in particular.
 
As something of a corollary to 501.140(B)(5), which states where the cords must be sealed, other cases in Division 2 are not required to be sealed. Basically, you can treat a cord that is otherwise acceptable under 501.140 as a multiconductor cable installed per 501.15(E) in general, and probably 501.15(E)(3) in particular.

Unless it enters a device which is itself XP due to what it contains. Which can be true for either or both ends.
 
J Box one end, 3 phase motor on other.

(B) Class I, Division 2.​
In Class I, Division 2 locations, motors, generators, and other rotating electrical machinery in which are employed sliding contacts, centrifugal or other types of switching mechanism (including motor overcurrent, overloading, and overtemperature devices), or integral resistance devices, either while starting or while running, shall be identified for Class I, Division 1 locations, unless such sliding contacts, switching mechanisms, and resistance devices are provided with enclosures identified for Class I, Division 2 locations in accordance with 501.105(B). The exposed surface of space heaters used to prevent condensation of moisture during shutdown periods shall not exceed 80 percent of the ignition temperature in degrees Celsius of the gas or vapor involved when operated at rated voltage, and the maximum surface temperature [based on a 40?C (104?F) ambient] shall be permanently marked on a visible nameplate mounted on the motor. Otherwise, space heaters shall be identified for Class I, Division 2 locations. 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.

.......................................................

If your motor is labeled Cl.I, D.1 as per the above highlight, then a seal would be necessary.
-------------------------------------------

501.10 Wiring Methods.......
(B) Class I, Division 2.......
(4) Boxes and Fittings.
Boxes and fittings shall not be required to be explosionproof except as required by 501.105(B)(1), 501.115(B)(1), and 501.150(B)(1).


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If the junction box is subject to the exceptions then the cable entering into it must be saled.

In both cases you are not sealing the conduit, per se, but rather the XP enclosures to contain the potential explosion internal to those.
 

rbalex

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I don't believe I disagree with anything you said, but all indications of the OP and Augie?s subsequent responses was that we are talking about a conventional 3-phase, TEFC motor wired through an enclosure that contains only terminations in a Class I, Division 2 location. Your highlighted reference from 501.125(B) basically applies to the motor auxiliaries, and under most conditions they apply to single-phase motors ? in which case the entire motor would most likely need to need explosionproof and cable seals required.

In general, I only try to answer the question(s) asked. Occasionally, there is sufficient evidence that more information about the specific installation is necessary and I will ask for clarification. Otherwise, Classified location discussions tend to become an exercise in rabbit chasing.
 

augie47

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Location
Tennessee
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State Electrical Inspector (Retired)
Gentlemen:
I apologize for not providing more specific input but as of this date my access to the area has been limited to a visual overview only (from a doorway).
I have been advised the entire room is Class 1 Div 2 and the cords drew my attention. In all probability the motors are 3 phase 480 TEFC.
 
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