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NEC Code and 'Control Panel Benchboards'

Discussion in 'Electrical Engineering' started by daestrom, Aug 9, 2011.

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  1. daestrom

    daestrom Guest

    Hi all,

    We have some control panel bench-boards, built in the mid 1980's. The
    front is about 8 ft high and 30 ft wide with an assortment of controls
    and such. They are totally enclosed with access doors on the back (that
    are *not* lockable).

    All the power/circuits going in/out are in conduit or armored cable.
    But *inside* the panel, the wiring between terminal boards and
    components is just single conductor or paired conductor wiring of
    appropriate size, routed neatly in trays and harnesses.

    Also *inside*, are some simple duplex receptacles (standard, 3-prong,
    120V). On the drawings, these are labeled simply, 'convenience
    receptacles' for maintenance personnel when working in the panel. They
    have a pair of 12 gauge wires (twisted pair) for the hot and neutral,
    and a separate 12 gauge wire tied to the frame ground bus-bar in the
    panel (the frame ground is 1/4 x 2 copper bar that runs the length of
    the panel, and is tied to building grounding with large copper strand).

    So, along comes an OSHA inspector who says, "Since that is a 120V
    receptacle, the feed to it must be in conduit as per NEC for all
    commercial buildings." And he promptly quotes the paragraph for
    receptacle outlets used in building wiring. He seems to think that
    since the wires are single conductor, there is some sort of increased
    risk that the user could come in contact with a frayed wire feeding the
    receptacle (never-mind all the other wires and terminals inside the

    I'm trying to argue that when this panel was built, it supposedly was
    built to all codes, and the wiring *inside* the panel is not 'building
    wiring' that needs to be encased in separate conduit. I thought the
    reason for armor/thin-wall was to protect the wiring inside walls/floors
    from damage because you can't see exactly where they are. Like when a
    carpenter drives in a nail or plumber drills a hole for pipe. These
    wires, inside the panel, are protected by the panel itself, right?

    The OSHA inspector didn't think the other 120V and 208V wiring in the
    panel was a problem, just the wiring to the receptacles.

    Any thoughts/opinions about the receptacle wiring? Do we need to go
    back and re-wire those specific circuits, even inside this bench-board /
    panel with armored cable or thin-wall conduit?

    Thanks for any constructive comments, I could use a citation or
    something to get this guy off my back (he's not a master electrician,
    nor EE, just some guy with a copy of NEC and OSHA safety regs).

    P.S. Considering all the other wiring *inside* I don't see the point,
    but some OSHA inspector seems to think it makes a difference.

    P.P.S. Forgot to also mention that all the receptacle circuits are
    protected by 15A GFCI's
  2. Rich.

    Rich. Guest

    1. There is no such article in the NEC that requires receptacle feeds to be
    in conduit.
    2. In the case of a factory assembled enclosure, the NEC does not apply. The
    NEC only applies to the branch circuit running from the breaker panel to the
  3. Bill

    Bill Guest

    1. There is no such article in the NEC that requires receptacle
    I agree with the above... However I think I would choose to NOT go to
    battle with an OSHA inspector! Or in other words, I would not want an
    OSHA inspector mad at me or my company.

    I think the most stress free and least expensive solution to this
    would be to do what he wants (if you know what I mean!)
  4. Rich.

    Rich. Guest

    That's a complete load of bunk, this OSHA inspector needs to be corrected.
    Since he's wrong about this, how many other things is he wrong about that
    other companies have had to needlessly pay the price for!?
  5. daestrom

    daestrom Guest


    Since the manufacturer put two outlets every five feet, that's a lot of
    rewiring. And since the inside of the panel has a lot of other
    individual conductor wiring, it seems silly that one particular circuit
    should have to be in conduit/armor.

    And I'm a little worried about having an electrician come into this
    panel (have to de-energize it for the work and that's a scheduling
    hassle). Afraid some other wiring might get damaged in the process of
    installing this new conduit/armor circuit. There is a *lot* of wiring
    in this thing, lots of control switches, indicating lights,
    annunciators, meters and controls. If something else gets damaged, not
    that I don't trust the electricians, and then we'll have to fix that too.

    I'd like to leave well enough alone and just point to him the
    chapter/verse that says factory manufactured panels are exempt. Or that
    such control panel / bench-boards are exempt.

    But thanks, I *do* understand 'picking your battles' :)

  6. Eric Tappert

    Eric Tappert Guest

    Article 409 of the NEC covers industrial control panels and the wiring
    contained in them. It has no references to "convenience outlets", but
    these have been used inside control panels for decades. Their use is
    for supplementary lighting, test equipment, and small tools. The
    panels are not required to be listed. There is no mention of
    "convenience outlets" in the code, but if they provide power to
    equipment in the panel they could be considered "disconnects". On the
    other hand, it they are for maintenance purposes, then the fact that
    they are enclosed in a panel means that they are not readily
    accessible, thus not subject to the same wiring rules as building

    Try labeling them as "For panel maintenace only" and see if that

  7. Bill

    Bill Guest

    For a business, the question is how much is it going to cost and what
    is the LEAST expensive route to take. FYI - I found the following...

    ["Upon inspection, if an imminent danger situation is found, the
    compliance officer will ask the employer to voluntarily abate the
    hazard and to remove endangered employees from exposure. Should the
    employer fail to do this, OSHA, through the regional solicitor, may
    apply to the nearest Federal District Court for appropriate legal
    action to correct the situation. Before the OSHA inspector leaves the
    workplace, he or she will advise all affected employees of the hazard
    and post an imminent danger notice. Judicial action can produce a
    temporary restraining order (immediate shutdown) of the operation or
    section of the workplace where the imminent danger exists."]

    The above sounds like a lawyer thing. If you have to send a lawyer to
    court, it is not cheap! And if you want to "go to battle with OSHA",
    then that would mean more lawyer time.

    Also I found this on the same page...

    ["Other Than Serious Violation - A violation that has a direct
    relationship to job safety and health, but probably would not cause
    death or serious physical harm. A proposed penalty of up to $7,000 for
    each violation is discretionary."]

    I suppose if the OSHA inspector is ticked, he could cause some trouble
    like the above. Then you are guilty until proven innocent. Get out
    that lawyer again!

    All I am saying is that if it costs $2000.00 to have the electrical
    work done and that is less than the cost of hiring a lawyer or paying
    a fine, then that might be the better 'business decision".

    FYI the above is from the following page...
  8. Rich.

    Rich. Guest

    You're assuming it's a one time thing. What happens when this mis-informed
    OSHA inspector writes up something again next month, and the next, and the
    next...then what?

    Taking the easy way out is what perpetuates these type of injustices. Plus
    this is just one business; multiply his error(s) by the number of businesses
    he frequents. Then the overall cost gets up into the 10s or even 100s of
    thousands of dollars.
  9. daestrom

    daestrom Guest

    Thanks for all the above, good info that I'll mull over.

    The benchboards were custom built by a manufacturer, so they are not a
    commercial-off-the-shelf type of panel and hence not U/L listed.

    The original contract (took some digging to find), stated they were
    built to NEC 1978 (current at the time) regarding the wiring to/from the
    panel (raised floor, so everything is in conduit/armor cable going
    in/out). But again, we couldn't find anything that would require
    conduit inside the panels.

    The opinion of one local inspector is that "If they were part of the
    panel as supplied by the manufacturer, fine. But if you add new ones
    yourself after installation, they would need conduit/armor." Since
    these are all original equipment, that would be okay by us. But we
    can't find anything like that in writing.

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