Panel Clearance

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usher

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Hi,

Can anyone direct me to the NEC code where it states piping cant be underneath an electrical panel. I am looking at an installation (see attached picture) and to me it doesn't look like a right installation.

This piping is going underneath a UL 508A industrial machinery panel(460V).

can anyone comment on the integrity of this installation?
 

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I see see it getting tricky. Are all the components in question (panels, piping, etc) part of a NRTL listed pieced of equipment ??
 
The article you are looking for is 110.26(E). But it does not apply to your situation. Only four specific things are forbidden to have pipes, ducts, or other foreign systems located directly above or below them. An industrial control panel is not one of the four.
 
augie47 said:
I see see it getting tricky. Are all the components in question (panels, piping, etc) part of a NRTL listed pieced of equipment ??
Click to expand...

Yes, all of them are NRTL listed.


charlie b said:
The article you are looking for is 110.26(E). But it does not apply to your situation. Only four specific things are forbidden to have pipes, ducts, or other foreign systems located directly above or below them. An industrial control panel is not one of the four.
Click to expand...

The panel has overcurrent device for motors / a small transformer and some control circuitry. doesn't it fall under Panelboard?
 
usher said:
The panel has overcurrent device for motors / a small transformer and some control circuitry. doesn't it fall under Panelboard?
Click to expand...

Panelboard. A single panel or group of panel units designed
for assembly in the form of a single panel, including
buses and automatic overcurrent devices, and equipped
with or without switches for the control of light, heat, or
power circuits; designed to be placed in a cabinet or cutout
box placed in or against a wall, partition, or other support;
and accessible only from the front.
 
Clearances

Clearances

usher said:
Hi,

Can anyone direct me to the NEC code where it states piping cant be underneath an electrical panel. I am looking at an installation (see attached picture) and to me it doesn't look like a right installation.

This piping is going underneath a UL 508A industrial machinery panel(460V).

can anyone comment on the integrity of this installation?
Click to expand...

Please note also that clearances required by 110-26 are measured from the front of the panel or equipment.
 
dkidd said:
110.26 (A) doesn't apply.
Click to expand...

what makes you think that?

personally, my opinion is that the piping is part of the system the ICP controls. and does not stick out more then 6 inches, it is OK.

(3) Height of Working Space. The work space shall be
clear and extend from the grade, floor, or platform to a height
of 2.0 m (61⁄2 ft) or the height of the equipment, whichever is
greater. Within the height requirements of this section, other
equipment that is associated with the electrical installation and
is located above or below the electrical equipment shall be
permitted to extend not more than 150 mm (6 in.) beyond the
front of the electrical equipment.
Click to expand...
 
usher said:
The panel has overcurrent device for motors / a small transformer and some control circuitry. doesn't it fall under Panelboard?
Click to expand...
No it doesn't, as one could infer from the definition that has already been posted.

I have long believed (with no documented proof that I am right) that the reason for the "dedicated space" rule has to do with the likelihood of additional conduits being installed at a future date. Each of the four items on the list (i.e., switchgear, switchboard, MCC, and Panelboard) would be installed with a given number of conduits leading to a given number of loads. But you are likely to add more conduits later, to accommodate future loads. So the room above and below the item is reserved to allow room for the future conduits. An industrial control panel will not require the future addition of more conduits. Neither would a transformer, a fused disconnect, a VFD, an alarm panel, or any other electrical enclosure I can think of naming right now. Again, this notion is not spelled out in the rule. But to me, at least, it makes the rule make sense.

 
MY 2 cents worth,.//
I thin 110.26(A) would apply to all NEC governed installations {110.26(E) only applies to that equipment charlieb listed)
If this equipment is a NRTL listed piece of equipment (the entire assembly, not individual components, the the applicable rule would apply and not necessarily the NEC.
If the NEC is applicable then, again IMO, the pipe could not protrude into the equipment space unless it is associated with the electrical install in which case it could not exceed 6" beyond the front of the equipment per 110.26(A)(3)
 
I think it unlikely the assembly is actually listed. People often think it is because the control is listed. But I have yet to run across a skid like this that the whole skid is listed where the control panel is UL 508a listed. There may be some out there but I have not seen one. I am told some load banks are done this way with the assembly listed under category code NMTR and the ICP to UL508a. I have not actually seen one though.

ETA: I have been told some HVAC skids are done in a similar manner but never seen one that is.
 
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