I recieved some violations:

1. Provide suitable outlet boxes for all installed emergency lighting and exit sign equipment identifying it as suitable for connection to a metallic wiring method, or provide access to this equipemtn to verify internal bonding means. MEC 314.3


....what I did was ran MC, from a j-box went over a foot, then through a concrete block into the back of an all plastic emergency light., no internal bonding avalible. This is Michigan so MC cannot be used for grounding/bonding.

wait, wait ok I guess could open my code book every once in awhile.. I would need non metallic. How should I do this... put a j-box in the opposite side of the cement block and run... erm.. something non metallic... romex? that doesn't sound right... its an old apartment building they turned into condos.

Maybe run ENT?

Trick:
Are you saying you ran MC into the KO at the back of the exit unit? I assume you connected the EGC in the MC to the grd connection within the exit unit, right?

Then based on what you said above.....open the exit unit so the AHJ can see the EGC connection within the device.

Or...does MEC 314.3 require a 'box' at each device (luminaire) location?

This appears pretty typical. Assumeing there is a connector.

"MEC" this tells me it's a local thing, open the book.

Edit: Heres a link to your amendments.
http://www.michigan.gov/documents/cis/dleg_bcc_2005_electrical_code_part8_207447_7.pdf

Yup thats what I did but, Theres no EGC in the exit light.
It came to me last night I should run seal tight.

I am curious on the reasoning for not being able to run MC to the plastic exit sign. The MC is bonded to the j-box its being fed from.... So anyone know the reasoning for this rule. Its certainly in the code book.

MEC 314.3 is the same as NEC 314.3

I should run seal tight--

ALL plastic, typicaly there is a metal core.

Or mount a metal box behind the fixture.

I too would like to get an inspectors take on this.

This is saying in other words you cannot run a metal raceway to a Plastic or nonconductive box>>>>?????

I think you should be able to bond the MC at the feed end and be OK but if they want it at both ends why not use a metal fitting with a bonding locknut/bushing attached to the internal EGC?

I have NEVER seen a plastic exit unit without a ground conductor included within the factory wiring to the circuit board.

Leland: Nice link, Thanks

I would like to add that the MEC does allow MC cable with it's grounding means — but if there is nothing at the load end to ground DUH??? If the EM light is nonmetallic then there is no issue. Now if there is a j-box on the fixture it's worth looking at for the option of a feed thru if needed.

Just drill a hole and tap a 10-32 and install a ground screw in the plastic.....................................................



Just Kidding I did work for a shop where we had a guy do just this with all the plastic nail on boxes. He spent the whole doing it. He was let go the next day.

Anyway, sounds like a good install to me, unless there is a grounding tail in the fixture for the electronics.

Ob

As long as the screw was green.

I got the idea that the AHJ wanted the armor of the MC bonded per 314.3 and suggested it would work with a bonding bushing as per 314.3 ex2.

heres an update.

I had this inspector out at this location on a different inspection and we got to talk about the MC cable and the exit/emergency light combos. I through out some big words like 'intergrated wiring compartments' and told how it is bonded at the j-box where the MC originated from just a few feet away. All he asked was if the unit was UL listed, and then said it was an 'OK' install.

Not much explination on the original violation other than he was concerned about bonding. I'm kinda thinking he wanted to meet me and let me know who the boss was....

So... MC to a 'intigrated wiring compartment' is a good install.

I'm glad the matter was resolved.

I've noticed the lack of a ground wire terminal on exit signs as well. I've also puzzled over the presence of a ground wire terminal on plastic junction boxes.

While some wiring methods always have a ground wire (NM, MC, etc.), you don't always need that ground wire at the end of the run. Exit signs are one such example. I think the boxes have the lug just to give you a place to tie the wire down.

Is this connected to a metal mounting strap? If so, it is to bond steel framing. (a new Florida law)

Ask the inspector if he requires bonding to plastic water pipes too. He must not be very busy to call you on this one.
Or he is just an idiot.

You could have mounted a 4 inch square by 1 1/2 on the surface and ran EMT down to the box and mount the exit on the box.