Plugs on lighting circuit - commercial

[rookie4now]

Good morning everyone,

I was just having a discussion with a coworker who does commercial. He was explaining that I made an error by adding a light to an existing circuit that was servicing outlets in a commercial office space. I told him that there were only 6 outlets on the circuit and therefore the loading was not a problem. He said that in commercial you cannot have receptacles and lighting on the same circuit. I didn't know this so I asked for the code reference so I can understand it, but he couldn't tell me the code reference off the top of his head and I couldn't find it. Does anyone know what the code section pertaining to this is?

I thought that 220.13 was telling me specifically that I COULD do this, but perhaps that is just for calculation purposes.

"In other than dwelling units, receptacle loads of computed at not more that 180va per outlet accordance with 220.3(B)(9)...shall be permitted to be added to the lighting loads abd made subject to the demand factors given in table 210.11..."

 

[acrwc10]

You asked the right question of your co-worker" give me a code referance". The reason that you would not have plugs and lights on the same circuit in most commercial jobs would be that many buildings use 277volt on the lighting.

 

[cowboyjwc]

I agree. We discussed this sort of thing just the other day in another thread. It's just another one of those myths.

 

[rookie4now]

Thanks. I'll make sure not to install any 277v outlets ;-)

 

[dnem]

Even tho it's not a code issue, if your prints show plugs and lights separate, that's the way they must be installed. . The Architect or Engineer is taking responsibility for the design and his specs must be followed.

Designers like to separate plugs and lighting for a couple of reasons. . One is that plugged-in motor loads cause less light dimming on startup if not on the same circuit. . This is even the case with something as small as a hairdryer. . Another reason is that the wattage of the lamps in the light fixtures can be speced and determined with precision and less "fudge" room is required in those circuits. . They can be maxed out without worry.

David

 

[charlie b]

In other than dwelling units, receptacle loads of computed at not more that 180va per outlet accordance with 220.3(B)(9)...shall be permitted to be ADDED TO (my emphasis) the lighting loads and made subject to the demand factors given in table 210.11..."

That is a calculation thing only. They are not talking about adding in the sense of "installing" a receptacle on a lighting circuit. They are talking about adding in the sense of arithmetics: add two numbers then apply the demand factors.