ECN Forum

CALC OF SERVICE SERVING RECESSED LUMINAIRES

Posted By: patrick1

CALC OF SERVICE SERVING RECESSED LUMINAIRES - 10/21/13 05:51 AM

It has my contention as an inspector, that the maximum wattage of the recessed luminaries be added to the wattage of calculating service sizes. I ordinarily ask contractors to consider the circuits that need to be added to cover amps added to accommodate this is above the minimum 3VA per square foot. 110.3 210.11 are my ordinary references with this grey area. I am having a discussion with my supervisor about this and having some resistance. I have had a bit of mental block after concussion and literally reading NEC 02,and 08 all over.

I need a bit of help with more code references besides what I referenced above or tell me I am wrong. Thanks all!
Posted By: shortcircuit

Re: CALC OF SERVICE SERVING RECESSED LUMINAIRES - 10/21/13 12:01 PM

I always understood that if you calculate the lighting load at 3VA per square foot for lighting that covered all lighting load. Of coarse this is a minimum standard.

Now with all the energy standards, lighting loads with be less. For example, our energy code requires a minimum of 50% of new lighting to be energy efficient such as CFL or LED.
Posted By: wire_twister

Re: CALC OF SERVICE SERVING RECESSED LUMINAIRES - 10/21/13 01:03 PM

I am with shortcircuit, I understood the 3va per sqft was for lighting and general purpose receptacle loads. Also with the LEDs for can lights getting cheaper I see more and more of those going in, this takes a maximum 65 watt fixture and makes it a 3 or 5 watt fixture. So the way I see it adding the extra 3 VA would just be insurance that the service has the capacity to carry any future loads that might be added, and I see nothing wrong with that.
Posted By: patrick1

Re: CALC OF SERVICE SERVING RECESSED LUMINAIRES - 10/21/13 02:16 PM

I do agree with the energy codes being able to lower wattage at the time of construction, however, when construction is done, if a fixture is not fitted with a non reversing adaptor that would only allow for a particular bulb; there is no guarantee that the bulbs won't end up being the maximum allowed for the recessed luminaire. Also, I see where CFL bulbs might be non-linear as well as any lighting location being continuous. This is not usually an issue when only 4 or 5 recessed luminaries are installed but when 12-100 recessed luminaries get installed and are not accounted for.
Thank you again, in advance for all input.
Posted By: shortcircuit

Re: CALC OF SERVICE SERVING RECESSED LUMINAIRES - 10/21/13 04:01 PM

All do respect...but I don't think you should require anything outside of what the code requires.

With the lighting, I would expect that people will want to save on their electric bill and replace with energy efficient bulbs.

With the 3VA per sqft we also can't prevent the end user from plugging in high loads to the receptacle outlets either. The code isn't a design manual, but a minimum safety standard.

Posted By: HotLine1

Re: CALC OF SERVICE SERVING RECESSED LUMINAIRES - 10/21/13 05:14 PM

Patrick1:

An old sage once told me.....'you are not a fortune teller, and you cannot see the future, and the inspection is for what is here now'.

3va per sq ft takes care of it.

BTW, have you ever monitored a 200 amp resi service for the actual load?

Posted By: gfretwell

Re: CALC OF SERVICE SERVING RECESSED LUMINAIRES - 10/21/13 07:50 PM

Patrick, you should be looking at article 220 for your load calcs and look at the examples in annex D in the back to see how all of that works.

The 3va from table 220.12 is all of the general lighting load for the occupancies it applies to but the footnotes at the bottom have additional adjustments for occupancies like offices that will end up being 4.5va when you apply them 220.14(k).
220.14(J) points out the required outlets in a dwelling that do not trigger any additional load allowance (bathrooms, garages, basements and the required lighting outlets). You still add in the laundry and small appliance circuits in the kitchen at 1500va per circuit 220.52(A)(4500va total).
Posted By: patrick1

Re: CALC OF SERVICE SERVING RECESSED LUMINAIRES - 10/23/13 03:44 AM

Thanks everyone for the valuable input. I do appreciate it.

Pat
Posted By: ghost307

Re: CALC OF SERVICE SERVING RECESSED LUMINAIRES - 10/24/13 02:40 PM

Here in Chicago the logic behind allowances for individual fixtures (such as downlights) is that no matter what wattage lamps are installed initially someone will decide that it's too dark and go to the DIY store, buy a bigger lamp, stand on a chair and stick it in the fixture.

As such, the requirement here is to allow for the maximum that CAN be installed instead of what is called for on the plans.

However, the incoming is sized per Article 220 regardless of how it's broken down once it comes into the building.
Posted By: gfretwell

Re: CALC OF SERVICE SERVING RECESSED LUMINAIRES - 10/25/13 05:47 AM

Quote
As such, the requirement here is to allow for the maximum that CAN be installed instead of what is called for on the plans.


How many VA do you rate a can for? 250? 150? 75? plus 25%?
Posted By: ghost307

Re: CALC OF SERVICE SERVING RECESSED LUMINAIRES - 10/25/13 02:57 PM

Whatever the manufacturer says the maximum lamp rating that it is designed for. Generally for medium base Edison sockets that is usually 150 Watts (no 125% needed).
Posted By: gfretwell

Re: CALC OF SERVICE SERVING RECESSED LUMINAIRES - 10/25/13 06:22 PM

Most regular edison base lamp holders are marked "250w". That seems to be the biggest bulb you can buy without going to a mogul. I have a 200w in the lamp next to my chair as we speak (on a dimmer). I am old and 200 might not be enough if I am doing some close work.

"Get out of my light" wink
Posted By: HotLine1

Re: CALC OF SERVICE SERVING RECESSED LUMINAIRES - 10/26/13 12:51 AM

Greg:
A 200 watt bulb? Last I was in 'big orange' incandescent bulbs looked pretty scarce. It's even tough to find a 60 watt yellow bug bulb.
Posted By: gfretwell

Re: CALC OF SERVICE SERVING RECESSED LUMINAIRES - 10/26/13 07:51 AM

That must be a local thing. I have no problem buying 150s and 200s. It is the 60 and 100 A19s that were phased out.
Posted By: HotLine1

Re: CALC OF SERVICE SERVING RECESSED LUMINAIRES - 10/26/13 06:36 PM

Shelves are full of all kinds of CFLs and LEDs.

Even saw some LEDs on 'clearance-markdown'!

I'm hunting for an equivilent 60 watt CFL 'bug bulb'.
The two I recently got seem to be eq. to a 15 watt incd.!!

Posted By: gfretwell

Re: CALC OF SERVICE SERVING RECESSED LUMINAIRES - 10/26/13 07:05 PM

If they are phasing out the regular A19s there you can always go for a halogen replacement.
© 2019 ECN Electrical Forums