Working space in front of MV metering cabinet

[MEdgarCI]

I'm looking at a situation where I have a pad mount MV metering cabinet with the CT/PTs in the rear compartment, and the meters are installed inside the dead-front compartment. In front this enclosure on the same pad is another piece of equipment.

What should the working clearance be? We are looking at this as Condition 3, voltage coming into the metering cabinet is 12.47kV.

I have two conflicting interpretations in Art. 110 regarding the minimum working clearances and am looking for clarification.

Interpretation #1
9' required as the highest voltage in the equipment is 12.47kV.

Interpretation #2
5' required as the voltage on the exposed side is <600V. Since there is isolation between the 12.47kV section and the dead-front compartment, we are allowed to use the lower voltage ratings to determine working clearances.

Thanks!

Michael

 

[Fnewman]

110.34 Work Space and Guarding.
(A) Working Space. Except as elsewhere required or permitted
in this Code, equipment likely to require examination, adjust-
ment, servicing, or maintenance equipment while energized shall have
clear working space in the direction of access to live parts of
the electrical equipment and shall be not less than specified in
Table 110.34(A).

Based on on the wording of this section and your description of the equipment, it is doubtful that the equipment will require examination, adjustment, servicing, or maintenance while energized, so the 9 ft. space would not seem to be required.