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I sell electrical devices across the country. My devices plug into a 120V wall outlet with a rubber-jacketed cord (3x18 gage conductors) that has a 3 prong NEMA 5-15 plug. The cord feeds AC power to my device which is contained in a PVC junction box. There are no metal parts exposed on the outside of this box, or on the inside. (no mounting plates for example) The device contains a tiny AC/DC convertor (enclosed in a smaller plastic box) which draws something like 50mA to power an LED and piezobuzzer. Is it required by the NEC or any other regulating body for my customers connect the (currently unused) ground wire in my cord? If so, why? (I don't see the point) And what would it be connected to?
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I would like to change my question a bit as follows in order to get a more encompassing answer:
There is no 3-prong plug as I said initially, instead, I am providing my customer with a 3-conductor wire that connects to my device. The 3-conductor wire is not connected to anything in my device because there is no place to connect it to - its a PVC outlet body with no metal parts outside or inside. (except wires leading to an AC/DC convertor which is enclosed in its own plastic box within the outlet body) The 3-conductor wire is to be "hard wired" to my customer's 120VAC or 240VAC electrical source. My question is:
1) Do I have to connect the ground wire to anything in my device?
2) Must my customers they connect the ground wire at their electrical source?
Please include NEC code references.
Thanks for the information.
As for your "device", has it been and labeled as UL approved?
That is the first thing that comes to mind.
The NEC does not nor has ever governed any piece of equipment, appliance or apparatus.
Equipment is approved by UL and when done so, it has already met the requirements that are associated in its UL category.
NEC covers wiring installations in all aspects of buildings and its surroundings.
No different than a light fixture or dishwasher etc. NEC has no ruling on these items.
They only rule on the permanent wiring of the structure to allow connection of the items
So, in your case, it appears there is no relation to the NEC, only UL.
As far as NEC on grounds, if it has metal of any type, grounding is required.
If there is no metal, then a ground cannot be established nor required.
But that pertains to the electrical system of the building and each part has a different article in the code.
Grounding is covered in 100+ locations as it pertains to each part of the electrical system of the building.
As an example, look at all the lamps, radios and other electrical appliances purchased. Most have no ground because of the UL approval.
They work with the appliances , not the NEC
Hope that helps, just reply for clarification ot other information.
Thanks Tommy, this is closing in on an answer, but I am still not clear on everything.
You are saying that NEC does not have authority over devices such as radios, or my device - but only wiring in buildings. But then you said:
As far as NEC on grounds, if it has metal of any type, grounding is required.
My device does have copper wires internally connected to the internal AC/DC convertor which is basically a pcb with a metal-core transformer. (also found in radios) So there must be some distinction as to the nature of the metal: do you mean external metal that can be touched by a person? (although many radios have this too in the form of antennas. Maybe you mean" "electrically connected external metal that can be touched by a person"? Please clarify.
Also from what you have said, it seems to me that if I provide my device with a NEMA plug then that is the magic point at which the NEC has no oversight like with a radio. However my device will be hard-wired to the building's wiring through a junction box, so doesn't that make it a permanent part of the building wiring and therefore subject to the NEC code?
From your answer "But that pertains to the electrical system of the building... "
So, I'm still not clear on if the ground wire must be connected or not. even though it doesn't seem to serve much purpose running for the 8 ft length of the wire and then dead-ending inside my device.
Ok, sorry for any confusion. Probably should have clarified what I was posting.
The NEC has no authority and does not dictate over appliances,radios, lamps etc or consumer products in general. Those fall solely under the UL.
I was just giving an example of what the NEC requires on equipment that is part of a structure and its wiring premises.
Like switches, receptacles, boxes etc.
Just for the situation, lets say that your item was actually part of a buildings wiring system.
Even if internal components have metal, it would be required to be grounded under the NEC. Any metal whether it is immediately accessible or only accessible after removing a cover is required to be grounded.
If there is no metal then it cannot be grounded, therefore not required.
Similar to running pvc pipe and pvc boxes with wires inside the conduit.
The boxes nor the conduit have any grounding capability because it is all plastic.
But when the wires emerge out of the pipe, if there is something with metal, then it is grounded at that point, otherwise you would not even run a ground wire.
But again, they do not govern as posted above.
If you have nothing metal inside or out, why use a 3 wire cord and plug, use a 2 wire only.
Hope that clarifies any confusion.
Thank you Tommy, just so I am clear: you are saying that the fact that my device is hard-wired does not have any bearing at all on whether it is subject to NEC regulations, instead the important thing is if my device is considered "equipment that is part of a structure and its wiring premises." Only this equipment is governed.
Well I can say that my device is not part of a structure, however I don't know if the term "wiring premises" contains a hidden meaning that would be unknown to a lay person so here is what I think it means by example:
In other words electrical devices that would be expected to serve any occupant of a building would be considered "wiring premises" but if a device has a specific purpose for only one occupant the it is not wiring premises? Is there a better definition?
If my above example is correct then my device would not be considered "wiring premises" and therefore would not be subject to any NEC regulations, and would therefore not require any grounding?
Using your example:Wiring that is considered part of the building (like an illuminated EXIT sign) would fall under the NEC regulations since the sign is required to be there by other regulatory authorities and is expected to always be in place. However if an occupant of the building installed an almost identical illuminated sign that read instead "ON AIR" (for a radio broadcast booth for example) then it would not be subject to NEC regulations because the sign is not considered a permanent part of the "wiring premises" of the building? In your example, the sign itself is under UL, not the NEC. The sign is a consumer product. In that case, NEC states to follow manufacturers recommendations when connecting and installing because the UL has already approved the drawings-wiring-components etc for consumer use.The wiring from the circuit breaker to the sign is under the NEC .The manufacture of the sign just like a table lamp, a radio,a fan, or any other consumer product and is not governed by NEC.I am not sure how else to word it or explain.Your item would be considered a consumer product and falls under the UL.The receptacle and wiring you plug it into would fall under NEC.
Hard wired or plug connected, it is still a consumer product for UL standards and not the NEC
OK so now it is clear to me that NEC does not govern the installation of anything beyond my customer's junction box. But I still don't have an answer to my original question which was:
My device, like thousands of other industrial products with a sales volume too small to justify UL's substantial fees, is not UL approved. Is there any regulating body or government agency that requires a product to meet UL's standard? Have approval that it meets the standard from a test lab?