UPS Clearance Issue

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MEPCor Inc

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San Diego CA
Good morning.
I’ve come across an issue with an engineer that I'm not totally 100% on and I don’t want to go into battle without all my T’s crossed and I’s dotted.

I have a situation where I am being told that the electrical clearances required above a panel don’t apply to and energized UPS. I don’t believe this is correct.
I have always stated that the six foot, or to the deck rule always applies and a UPS should be treated as a panel.

What are your thoughts?
 
I agree with engineer.

A UPS is not listed in 110.26(E) as needing dedicated space.

(E) Dedicated Equipment Space. All switchboards, switchgear,
panelboards, and motor control centers shall be located
in dedicated spaces and protected from damage.

I would see a UPS more similar to a transformer in this case, neither are listed because unlike the gear listed above one usually runs the input ant output conductors and that is it. One is not usually piping in more conduits or adding cables as loads change.
 
Switchgear is a defined term in Article 100; I would suggest most UPS systems meet that definition:

Switchgear. An assembly completely enclosed on all sides
and top with sheet metal (except for ventilating openings
and inspection windows) and containing primary power circuit
switching, interrupting devices, or both, with buses and
connections. The assembly may include control and auxiliary
devices. Access to the interior of the enclosure is provided
by doors, removable covers, or both.
Click to expand...
 
rbalex said:
Switchgear is a defined term in Article 100; I would suggest most UPS systems meet that definition:
Click to expand...

it says completely enclosed.

what about a UPS system that gets mounted into telco style racks as components? UPS's these days are not in a "box" like art 100 says.

@OP, what type of UPS is it your are dealing with ?
 
FionaZuppa said:
it says completely enclosed.

what about a UPS system that gets mounted into telco style racks as components? UPS's these days are not in a "box" like art 100 says.

@OP, what type of UPS is it your are dealing with ?
Click to expand...

Ehhhh, I don't know...
 
I have installed UPS systems up to 5000kW - floor mounted. The definition actually says, "...completely enclosed on all sides and top ..."; there would be no reason to specify the top if "all sides" required the bottom to be included.
 
110.13 (B).
(B) Cooling. Electrical equipment that depends on the
natural circulation of air and convection principles for cooling
of exposed surfaces shall be installed so that room
airflow over such surfaces is not prevented by walls or by
adjacent installed equipment. For equipment designed for
floor mounting, clearance between top surfaces and adjacent
surfaces shall be provided to dissipate rising warm air.
Electrical equipment provided with ventilating openings
shall be installed so that walls or other obstructions do not
prevent the free circulation of air through the equipment.
Click to expand...
Regardless of the type / style of UPS, that is still going to apply
 
Jraef said:
110.13 (B).

Regardless of the type / style of UPS, that is still going to apply
Click to expand...
my UPS in teleco rack is forced air cooling, a gazillion little muffin fans. its not natural convection, so should it still apply? although i see hiccup with the words "floor mounted" vs my rack mounted UPS's. but lets say its metal box that has floor mounting flanges but the UPS itself is forced air cooling?


natural convection
transformer-installation.jpg



versus a unit that requires fans

onaf-cooling.gif
 
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This comes up frequently. It is unfortunate, as it is prudent to provide equipment clearance regardless of the code, as it is a minimum. It is true: the code may be interpreted to exclude UPSs for these requirements. Is there an external maintenance bypass cabinet?

Concur with other posts: meet manufacturer minimum cooling clearances.

If the UPS has a distribution section within, you may have a leg to stand on.

NFPA 111 may give further legs to stand on.

We assume the working clearance was at least provided?
 
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