OC and disc means for cont panel

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Isaiah

Senior Member
Location
Baton Rouge
Occupation
Electrical Inspector
I have a 480VAC three phase feeder from a MCC, thermal Mag CB that runs 300 feet to a control panel on a Chiller unit. I am being told the control panel does NOT have an internal CB or disconnecting means.

I am telling the contractor he must supply a fused disconnect at the panel – I am citing 408.36. Are there others?
 

tom baker

First Chief Moderator
Staff member
Is the control panel UL508A listed?
What is the size of the branch ckt from the MCC?
Every Control panel I have installed (100 or so) has an internal disconnect, plus is labeled with the max short ckt available current.
I dont have a copy of UL 508A, but I am sure it requires a power disconnect in or at the panel.
 

Isaiah

Senior Member
Location
Baton Rouge
Occupation
Electrical Inspector
Is the control panel UL508A listed?
What is the size of the branch ckt from the MCC?
Every Control panel I have installed (100 or so) has an internal disconnect, plus is labeled with the max short ckt available current.
I dont have a copy of UL 508A, but I am sure it requires a power disconnect in or at the panel.

I'm told the branch circuit is #4/0. I am amazed they dont have this covered, with a disconnectiing means
 

augie47

Moderator
Staff member
Location
Tennessee
Occupation
State Electrical Inspector (Retired)
I would lean more toward 440.14 for a chiller disconnect.
The type disconnect would vary depending on the chiller protection requirements (fuse, breaker, size, etc)
 

petersonra

Senior Member
Location
Northern illinois
Occupation
engineer
I have a 480VAC three phase feeder from a MCC, thermal Mag CB that runs 300 feet to a control panel on a Chiller unit. I am being told the control panel does NOT have an internal CB or disconnecting means.

I am telling the contractor he must supply a fused disconnect at the panel – I am citing 408.36. Are there others?
408.36 is for panelboards. This is not a panelboard.
 

Isaiah

Senior Member
Location
Baton Rouge
Occupation
Electrical Inspector
I would lean more toward 440.14 for a chiller disconnect.
The type disconnect would vary depending on the chiller protection requirements (fuse, breaker, size, etc)

According to 440.14, a disconnecting means is not required if lockable per 430.102(A), where only qualified personnel will service the equipment - does this supersede UL508A and NEC 409?
 
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