277V Disconnect Clearance

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Cow

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I think what Infinity is getting at is if the 24v control panel on the other side qualifies as a grounded enclosure according to the table, the working clearance gets increased from 3 to 3.5 feet.

Read through the three conditions under the table. That helps explain the requirements.
 

infinity

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I think what Infinity is getting at is if the 24v control panel on the other side qualifies as a grounded enclosure according to the table, the working clearance gets increased from 3 to 3.5 feet.

Read through the three conditions under the table. That helps explain the requirements.


Yes, that's why I was asking. If it were in a plastic enclosure then the required space would be less.
 

don_resqcapt19

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Illinois
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I think the real question is "is this a condition 2 or a condition 3 installation?". Give the low voltage on one side, I am inclined to say it is a condition 2 installation and will require 42" of clearance.
 

infinity

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I think the real question is "is this a condition 2 or a condition 3 installation?". Give the low voltage on one side, I am inclined to say it is a condition 2 installation and will require 42" of clearance.

That was my thought as well, 277 volts on one side and a grounded enclosure on the other.
 
110.26(A) States 600v to ground.

The table, Condition 3 states live parts on both sides; Condition 2 states grounded parts on the other side of the working space.

There is permission in the NEC for some systems of voltages lower than 50v to be ungrounded.

We also have 110.26(A)(1)(b) Low Voltage.

So this may not be a simple question.
A little more info from the OP may help to come to an agreeable conclusion amongst us all. :cool:
 
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