small chiller disconnect means

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andy psenick

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I'm installing a minimate chiller which is for
a small ice surface.I was told that the amp rating was 15 amps.I'am coming from over a one hundred feet distance so I'm using number 10 wire off of a 3p/20amp bkr.My question is ,do I to have to use a fused 35amp? disconnect or a safety switch rated at or above? thank you.
 
Re: small chiller disconnect means

Are you putting a plug on it or hard wiring it? If it's a portable unit they will have a off/on switch on it that controls a contactor inside the unit. A disconnect is not needed and a 20 amp circuit to your recep. should be fine.
Jim
 
Re: small chiller disconnect means

Originally posted by james wuebker:
If it's a portable unit they will have a off/on switch on it that controls a contactor inside the unit. A disconnect is not needed and a 20 amp circuit to your recep. should be fine.
Jim
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You can not use a controller as the means of disconnect.

The required disconnect must open the ungrounded conductor directly.

My question is ,do I to have to use a fused 35amp? disconnect or a safety switch rated at or above? thank you.
Click to expand...
Yes it will need a disconnect, what size and fused or not will depend on the units labeling.

A 60 amp disconect with 35 amp fuses supplied by a 20 amp breaker is kind of a waste. ;)
 
Re: small chiller disconnect means

Bob,
I can not find any NEC prohibition of a controller as a disconnect. In fact, the exception to 430.84 specifically recognizes the possibility of a controller as a disconnect.
 
Re: small chiller disconnect means

Good morning Jim,

Originally posted by jim dungar:
Bob,
I can not find any NEC prohibition of a controller as a disconnect. In fact, the exception to 430.84 specifically recognizes the possibility of a controller as a disconnect.
Click to expand...
If you follow that exception you find they are talking about a Switch or Circuit Breaker as Both Controller and Disconnecting Means.

430.84 Need Not Open All Conductors.
The controller shall not be required to open all conductors to the motor.

Exception: Where the controller serves also as a disconnecting means, it shall open all ungrounded conductors to the motor as provided in 430.111.
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Part of 430.111
430.111 Switch or Circuit Breaker as Both Controller and Disconnecting Means.
A switch or circuit breaker shall be permitted to be used as both the controller and disconnecting means if it complies with 430.111(A) and is one of the types specified in 430.111(B).
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In other words if you opted to use a switch or circuit breaker as the controller it can also serve as the disconnecting means.
 
Re: small chiller disconnect means

iwire
You wrote(You can not use a controller as the means of disconnect.

The required disconnect must open the ungrounded conductor directly.
(iwire, this was what I was getting at.)
If your unit has a plug on it that plugs into a recep., you turn off the unit, unplug it and lock it out with a plug lock out devise. That's why I ask if it was going to be hard wired or plug in type. If you have ever been at a plasic injection molding company they use these all the time. The plug type will allow you to move from one machine to another if chilled water is needed.
Jim
 
Re: small chiller disconnect means

The controller is required to have a disconnect on the line side, so in general I don't see how you can use a controller as the required disconnect. Remember that the disconnect is required for lockout purposes and there is no way to lock out most controllers. If the controller is a switch, circuit breaker or cord and plug connection, then I agree that those and only those types of controllers can be used as the required disconnect.
Don
 
Re: small chiller disconnect means

Originally posted by james wuebker:
If your unit has a plug on it that plugs into a recep., you turn off the unit, unplug it and lock it out with a plug lock out devise.
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Jim I agree if it is cord and plug connected, I was speaking of hardwired equipment.

Andy did not specify.
 
Re: small chiller disconnect means

430.111(A) and 430.111(B)(1) allow a manual motor starter with direct acting contacts to be both a controller (with overloads as part of the switch) and a disconnect.
 
Re: small chiller disconnect means

Originally posted by jim dungar:
430.111(A) and 430.111(B)(1) allow a manual motor starter with direct acting contacts to be both a controller (with overloads as part of the switch) and a disconnect.
Click to expand...
Yes they do, look 4 posts above yours. :D
 
Re: small chiller disconnect means

Thank you for your responses on my questions.The unit is to be hardwired and be on the outside of the building.I realize for safety measures that the unit should have a means for disconnecting at the unit and for maintenance. [and a means to lock out also]. I do not have a cut out sheet on it yet but am trying to determine if a 30 amp saftey switch or a fused 30 amp disconnect would suffice on a start up surge? I was told by the supplier that it was rated for 15 amps minimun but that 20 amp was preferred.[3p/20amp/480V]Thanks again.
 
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