Providing a plug in-cord and receptacle for hardwired equipment

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lakee911

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Columbus, OH
In our industrial control panels we typically provide a UPS to keep our PLC systems running during an outage and until the backup generator comes online. In the panel we typically plug the UPS into a receptacle and then hardwire a cord to terminal blocks to plug into the UPS. This is fine because the NEC doesn't apply.

If I want to do the same thing for a UPS that is NOT provided in an industrial control panel, that is it is sitting on a shelf for example, how do I do that? I can obviously plug the UPS in. How would I go about interfacing the building wire to the UPS? Some how I need to plug it in.

Thanks,
Jason
 
I'm not sure what your asking. Not having a place next to the shelf to plug in the ups? (add a receptacle).

Interfacing a control panel to get power from the external ups? (add a male flange to the outside of panel)

Might want to clarify your question.
 
lakee911 said:
In our industrial control panels we typically provide a UPS to keep our PLC systems running during an outage and until the backup generator comes online. In the panel we typically plug the UPS into a receptacle and then hardwire a cord to terminal blocks to plug into the UPS. This is fine because the NEC doesn't apply.
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Remember that because you are wiring to terminal blocks that the load side remains energized when the disconnect is pulled. Therefore by industry standards those wires need to be ORANGE (was YELLOW). And the NEC still applies but you are doing industrial machine wiring not building/residential. The change in connection points makes most of the NEC non-applicable but not all of it.

lakee911 said:
If I want to do the same thing for a UPS that is NOT provided in an industrial control panel, that is it is sitting on a shelf for example, how do I do that? I can obviously plug the UPS in. How would I go about interfacing the building wire to the UPS? Some how I need to plug it in.

Thanks,
Jason
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Are you planning to hardwire the line or load side? In almost all cases you can and should just use a receptacle on the line side. In most cases you should still be using a plug into the load side. What are you connecting?
 
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pfalcon said:
Remember that because you are wiring to terminal blocks that the load side remains energized when the disconnect is pulled. Therefore by industry standards those wires need to be ORANGE (was YELLOW). And the NEC still applies but you are doing industrial machine wiring not building/residential. The change in connection points makes most of the NEC non-applicable but not all of it.
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We use orange wiring for foreign powered equipment (such as from an MCC to a dry contact in our panel), but wiring that is within our panel (even from a UPS) we don't consider a foreign voltage source. We provide a disconnecting means on the feed to the control panel and directly off of the load side of the UPS that is feeding. This allows us to kill power to most all of the panel. Perhaps the wiring from the load side of the UPS to said disconnect should be yellow...

We provide a nameplate stating what orange designates and state that there all multiple sources to disconnect.

pfalcon said:
Are you planning to hardwire the line or load side? In almost all cases you can and should just use a receptacle on the line side. In most cases you should still be using a plug into the load side. What are you connecting?
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We would provide a female receptacle fed from a circuit breaker in a lighting or power panel somewhere. To this we plug in the line side male plug of the UPS. That part is a no brainer.

Now, the confusion arrises because the UPS only has female receptacles. What if I had a hardwired (fed with building wire) receptacle in another room that I wanted on the load side of the UPS? How would I essentially make up a male plug that is connected to the building wire on one side and can plug into the UPS on the other? Is this where I would use a 'male flange' and then an extension cord?
 
I see no problem using a female receptacle to supply power _to_ the UPS, and a male inlet to permit the UPS to supply power to the permanent building wiring. You simply have an apparatus with two cords connected to building wiring. IMHO it makes no difference that one of these cords carries power from the building wiring, and one of these cords carries power to the building wiring.

Note that when this has been discussed in the past, others have suggested that this makes the flexible cable effectively part of the permanent building wire, which is of course a no-no.

-Jon
 
winnie said:
others have suggested that this makes the flexible cable effectively part of the permanent building wire, which is of course a no-no.

-Jon
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there is cable listed as both TC-ER and STOW, thus its both tray cable and portable cord. Would this be good for the application?

the other option is to mount a flanged inlet, and use a jumper cord between it and the ups.
 
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