Disconnecting Means Requirement of >1,000V chiller

T

TXMaster

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Hey, fellas. Trying to see everyone's thoughts on this topic:

There is a 4,160V chiller at an industrial facility. It has a remote across-the-line starter with a disconnect that is in a different room than the chiller, and there is no additional means of disconnect at the chiller itself. Can this be justified with exceptions?

440.14 implies there may be an exception if this chiller is used for an industrial process at a facility with written safety procedures, but that exception (No. 1) also references back to 430.102(A) which deals with motor controllers, not the equipment itself.

I read this as, in no case, shall the ACR equipment itself have a disconnecting means that is not within sight and readily accessible. I don't see an exception to the rule, but I'm not 100% sure of the intent of 440.14 (Exception No. 1). Why have that exception at all if it would only apply to a controller and not the equipment itself?
 
My guess is that 430.102(A)(1) might apply, since its over 1000 Volts.

I'm not sure if 440 applies to a chiller.

It looks like a "hermetic refrigerant motor compressor" has the motor and compressor in one sealed unit. I think a chiller is usually large enough the motor would be a standard motor? See the last sentence of 440.1.
 
steve66 said:
My guess is that 430.102(A)(1) might apply, since its over 1000 Volts.

I'm not sure if 440 applies to a chiller.

It looks like a "hermetic refrigerant motor compressor" has the motor and compressor in one sealed unit. I think a chiller is usually large enough the motor would be a standard motor? See the last sentence of 440.1.
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That is an interesting point. The first sentence of 440.1 says the article applies to electric motor-driven air-conditioning and refrigerating equipment, but the following sentences provide further information regarding hermetic refrigerant motor-compressors. A chiller this large is a rotary compressor and not hermetic. We may have found a gray area here... could come down to interpretation by the AHJ.

If I could just apply 430.102, I think the remote disconnecting means could be approved under the exceptions contained in 430.102(A) and 430.102(B).
 
Maybe the motor would be considered semi-hermetic.... it is a centrifugal compressor motor, and it is cooled by the refrigerant that it is moving. Assuming Article 440 does indeed apply.... do you see an exception for allowing a disconnect out of sight of the equipment?
 
If the motor is cooled by the refrigerant, then it is a hermetic or semi-Hermetic compressor AFAIK. 440.14 if I read it right applies to an open motor or a hermitic or semi hermetic motor AFAIK. if the conditions of industrial maintenance is valid and I would think it would be for a 4160 volt equipment I would think you would fall under the exception
 
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