How to provide dimmer wiring to hanging light (luminaire) when flexible cord with plug for the receptacle is requested

oceanobob

Member
Facility personnel request hanging luminaire with chain and hooks, and the electrical connection is via an outlet receptacle in the immediate area and a short flexible cord such a 300v 14-3 for a couple hundred watt max flour or LED. The idea is: when there is a problem, the item can be readily replaced with an on hand spare and the work station progress continues. The luminaire is repaired at a later time in the workshop.
This idea works well but with the added feature of the 0 to 10 volt dimming circuit, other electricians at the supply house said to forget about the existing method and consider MC cable which would be hardwired and put a damper on the existing scheme.

Any suggestions? Am planning on adding some luminaires (fixtures) in a new work area, thus have a clean slate for this project. EMT conduit exposed against roof rafters is the typical wiring method to the 4S box outlet - would like to keep receptacle at the outlet in the similar fashion.

I realize there is copious commentary regarding the 0-10 v and MC cable and the separation when using conduit and within all that I sincerely thank all for the contributions - but in the midst of all that I didnt see anything about this idea. Sorry if I missed it.
 

kwired

Electron manager
Location
NE Nebraska
0-10V circuit doesn't necessarily have to be separate on most (if not all) of these.

That said if you use a cord and plug you will either need an additional cord, and plug for the 0-10V or will need a 5 wire cord/plug/receptacle of some type if using the dimming feature.
 

GoldDigger

Moderator
Staff member
The code does not, I think, allow for a variable voltage to be supplied to a standard receptacle outlet. The only UL approved mechanisms for plugging a dimmable light into a controlled receptacle are the ones that use a non-standard receptacle that rejects standard portable lamp plugs.
In this case there seem to be two options:
1. Place the controllable ballast upstream of the receptacle and use a non-standard plug type, or
2. Feed uncontrolled line voltage to the receptacle and provide a separate pluggable mechanism for carrying the 0-10 control voltage to a dimmable ballast in the luminaire.
 

brantmacga

Senior Member
Location
Georgia
Occupation
Electrical contractor
I think your compliant option is going to be using something like a Lutron Vive wireless dimming module at each fixture, but at the expense of about $100 extra (plus labor) per fixture.


Sent from my iPhone using Tapatalk
 
Location
California
Occupation
Lighting
Use Lutron Power Paks at the affected fixtures and control the 0-10 dimming via wireless. This way you can keep the line power so corded assemblies, do not have any cross voltage system connection worries (via unlisted/un-approved multipole connectors), and do not have to employ MC cable with integral 0-10v cabling.
 

oceanobob

Member
I have continued to search on this topic on the net and by inquiring.

The latest idea is:
Raceway (deliberately vague here, may have to be a MC cable such as Southwire MC-PCS duo) to an outlet (4S type box).

Using the modular connectors: 3 wire for the 120 (or 277 depends on the facility's system) and a two wire for the purple gray 0-10v.

As to the flexible whip to the fixture, this would be the MC cable with the conductors for the line and the control as mentioned previously, terminate the exterior shield using the appropriate connector into both the fixture and at the outlet and further clarification: use a blank cover with the one (or two) KO knockout to the outlet.

Admittedly: A screwdriver is required to open the blank cover, then the two modular connectors can be unplugged to release the whip from the system.


This idea allows standard components, keeps all the wiring (line and low voltage) in the cable and is a LOL reasonable compromise to the good ole plug and cord that required no tools to remove and swap the fixture.

~~~~~~~~~~~~

And another idea being investigated is Cooper MWS (modular wiring system). I have requested contact with the rep will update as I learn more.

>>>>

When I went to attach the files for the cable and the MWS, the MC cable is half a meg but the MWS is a meg and a half and was too large. Hopefully you can find a link, fyi the Cooper website is indicated as 'non secure' on my system but the MC cable came from a trusted source (electrical supply house).

PS yes there can be the issue with the divider in the light fixture but in this case the LED high bay fixture we are considering is from Utopia and there is no divider but the wiring space is tiny LOL but they also sell a pendant adapter (we would not use a pendant, just like the box) which has a nice amount of room it is a decent solution to creating some space which makes the job more reliable and the cost of the extra space box is saved back in labor that would have to deal with the no room were the box not to be installed.

Thanks all for the assistance.
 

Attachments

Seems like a lot of work to make a "quickly" swappable light; AFAICT they only thing it saves is finding/turning off the breaker (and thus other lights) and a minute or so to undo some wire nuts and put them back. Oh, and having somebody qualified to do that, but they're probably around anyway. Unless everything is in place, it's still going to be 30-60 minutes to get everything together.

Are those worth the extra expense?
What's the expected failure rate?
With Lutron or similar, include the cost of the wireless interface to the control system
Must have wired 0-10v? I'd just use standard CAT5 cable and parts.
 
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