Commercial lighting

[tbakelis]

Hello All,

I'm an electrician with 10 years experience. Small shop in San Jose California (me and 1 employee, 1 van) I mainly do residential with a little commercial experience.

I'm trying to bid a commerical job (ice cream store, approximately 36 lights... 4x4s, 2x2s and some recessed lights all LED). I know there are a ton of new title 24 stuff of which I am not familiar with. Stuff dealing with the amount of daylight coming in and such.

Couple questions:
On the plans it shows four 0-10V LED dimmers controlling all of the stores lights. I'm not familiar with those. Any enlightenment on that? Are there separate low voltage control wires that go from light fixture to the dimmers for dimming?

I can't find anywhere on the plans any "lighting control panel". Just a 2 hr bypass switch of which I've done before. There are also 2 light fixtures that fall into a 9' daylight area by the front door. Can someone enlighten me on what is required of those 2 light fixtures that fall into that daylight zone?

I can totally handle this project because it isn't that big... just a little nervous about the lighting portion of it.

Any advice will help!

Thanks,

Ted

 

[Dennis Alwon]

This is from Lutron. Southwire cable company makes an MC cable for this purpose

0-10VDC (4-wire control):Ballasts controlled by this method require four controlwires: Switched Hot, Neutral, 0-10VDC Positive, and0-10VDC Negative. The Switched Hot and Neutral providepower to the ballast. The 0-10VDC wires provide thedimming signal from the control to ballasts.

 

[Dennis Alwon]

Here is the southwire product http://www.afcweb.com/mc-metal-clad-cables/mc-luminary/

 

[Fulthrotl]

I can't find anywhere on the plans any "lighting control panel". Just a 2 hr bypass switch of which I've done before. There are also 2 light fixtures that fall into a 9' daylight area by the front door. Can someone enlighten me on what is required of those 2 light fixtures that fall into that daylight zone?

I can totally handle this project because it isn't that big... just a little nervous about the lighting portion of it.

Any advice will help!

Thanks,

Ted

PM sent.

those two lights in the primary daylighting areas, are subject to automatic daylighting control if:

they are down lighting.
the total lighting load is over 120 watts in the primary daylighting area.
ornamental lights don't count in the lighting load, and aren't subject to automatic daylighting.

as for "lighting control panel", you need to do a couple things:
install what is specified on the stamped drawings
have it certified by someone with an acceptance testing certificate.

something to lessen the pain of all this, is to find who has to bless your work,
and involve him BEFORE you start throwing stuff up in the ceiling. not all electrical
engineers will draw compliant installations. sometimes, they know less than the installer
about T24:2013, especially if they are out of state, and haven't done much of this stuff.

if it's not capable of being certified, that will have to be fixed and plans sent thru plan
check again. then you can install something that can be signed off. the last thing you
want to do is have a project you installed according to print get all the way to final,
and you have the building inspector pass you, pending the lighting certificate, and then
you find out the whole thing is hosed and has to be done over.

a lot of times, engineers will make a primary daylighting zone half the size of vermont,
and specify daylighting where it is not required under part 6 of the code, just to cover
their butt.

a lot of times, they will combine separate, discrete zones into one massive zone, when
each zone, considered under the rules, does not require daylight harvesting.

 

[Fitzdrew516]

I can't stress enough that you read the actual energy code. The requirements are pretty extensive, but if you dedicate enough time to learning it it would make sense. If you don't want to waste the time on that I'd suggest as Fulthrotl did that you just talk it through with the AHJ before doing the work. Although in my experience with California work it seems a decent amount of plans reviewers and inspectors aren't even well versed on the latest requirements yet.

 

[tbakelis]

Thanks for the input guys. 100% of the lighting on this project are LED (28 trouffers and 9 recessed lights). The two light fixtures in the daylight area will not be over 120 watts. And I can't find anywhere on the plans any lighting control panel of any kind. They just have the 4 dimmers controlling all of the lighting and a 2 hour bypass timer.

That cable with the low voltage wires within it looks pricey but I'm assuming we make up the time with the labor hours.

So you guys are suggesting I take the plans down to the city and set up a time with the appropriate inspector to get his blessing and make sure the architect/engineer have got it right?

PM sent.

those two lights in the primary daylighting areas, are subject to automatic daylighting control if:

they are down lighting.
the total lighting load is over 120 watts in the primary daylighting area.
ornamental lights don't count in the lighting load, and aren't subject to automatic daylighting.

as for "lighting control panel", you need to do a couple things:
install what is specified on the stamped drawings
have it certified by someone with an acceptance testing certificate.

something to lessen the pain of all this, is to find who has to bless your work,
and involve him BEFORE you start throwing stuff up in the ceiling. not all electrical
engineers will draw compliant installations. sometimes, they know less than the installer
about T24:2013, especially if they are out of state, and haven't done much of this stuff.

if it's not capable of being certified, that will have to be fixed and plans sent thru plan
check again. then you can install something that can be signed off. the last thing you
want to do is have a project you installed according to print get all the way to final,
and you have the building inspector pass you, pending the lighting certificate, and then
you find out the whole thing is hosed and has to be done over.

a lot of times, engineers will make a primary daylighting zone half the size of vermont,
and specify daylighting where it is not required under part 6 of the code, just to cover
their butt.

a lot of times, they will combine separate, discrete zones into one massive zone, when
each zone, considered under the rules, does not require daylight harvesting.

 

[GoldDigger]

So you guys are suggesting I take the plans down to the city and set up a time with the appropriate inspector to get his blessing and make sure the architect/engineer have got it right?

have it certified by someone with an acceptance testing certificate.

The person with the credentials is most likely a contractor (like Fulthrotl) who will provide the certificate that the city inspector will want to see.
The city may or may not have name(s) to suggest for someone who works your area.
I think that what Ful is saying is that the person who should do a quick look at the plans is the person who will eventually be certifying it.

 

[tbakelis]

Thanks Dennis, Couple more questions:

Do they make that MC luminary cable in a 12/3 form? So that I can alternate fixtures for switching (per plans)

If I do the above, does the shared neutral create issues when dimming? (probably will right!?)

Here is the southwire product http://www.afcweb.com/mc-metal-clad-cables/mc-luminary/

 

[Fulthrotl]

The person with the credentials is most likely a contractor (like Fulthrotl) who will provide the certificate that the city inspector will want to see.
The city may or may not have name(s) to suggest for someone who works your area.
I think that what Ful is saying is that the person who should do a quick look at the plans is the person who will eventually be certifying it.

yep. all of that.

people who don't do all of that resemble the fellow who called me at 8:45 this morning,
needing a certificate, for tomorrow if possible. he'll get his certificate tomorrow, but,
well, it's not cheap.... he's 400 miles away, in santa cruz.

camarillo first thing in the morning, the santa cruz, then back home.... it'll
be a 850 mile day.... the trick is to miss traffic at both ends of the trip, coming
and going..... traffic into santa cruz is damn near unbearable. the last 4 miles,
at the wrong time, was an hour and a half the last time i timed it wrong.

 

[iwire]

Thanks Dennis, Couple more questions:

Do they make that MC luminary cable in a 12/3 form? So that I can alternate fixtures for switching (per plans)

If I do the above, does the shared neutral create issues when dimming? (probably will right!?)

The real problem with using multiwire branch circuits is the required handle tie on the breaker.

 

[tbakelis]

The real problem with using multiwire branch circuits is the required handle tie on the breaker.

It will be same circuit, just 2 switchables sharing neutral. Does that create issues w the low voltage dimming?

 

[ActionDave]

It will be same circuit, just 2 switchables sharing neutral. Does that create issues w the low voltage dimming?

It means that if there is a problem with one of the circuits you have to shut both of them off.

 

[Fulthrotl]

It will be same circuit, just 2 switchables sharing neutral. Does that create issues w the low voltage dimming?

i don't know how much of a problem it might cause, but i when i was doing
a lighting test, and had a fluke 345 clamped on the lighting circuit, what
all those dimmers do as far as putting noise and trashing the waveform
in the circuit is pretty significant. after getting the power reading on
the circuit, i switched it over to the scope position, and it was hard
to identify it as alternating current. i think i'd put the receptacles
on a different circuit.