Dimming can lights

[DanZ]

Guys,

I've got an odd situation. I am doing a lighting layout for a Endodontist, who's office office has 3 outside walls that are floor to ceiling windows. These walls are where the treatment rooms are. The Doctors would like to have 4 can lights per treatment room, instead of the "normal" 2x4 fluorescent fixtures. I noticed that at their other office, in some rooms that they have removed the lamps from the cans, because it was too bright in the room. I suggested putting the cans on dimmers so they could vary the amount of light they needed, and they liked that idea.

I'm doing the Com Check (required to get a permit) and with the square footage, and other lights in the space, I can only put a 45 watt incandescent lamp in the fixture to meet energy code. My other option is to use a dimmable CFL, but I have heard of problems with them dimming correctly.

Have you guys heard of or used any dimmable CFLs that worked well?

Thanks,
Dan

 

[Dennis Alwon]

Have you guys heard of or used any dimmable CFLs that worked well?

Thanks,
Dan

Dan there are some CFL's that say they are dimmable but they do not appear to work in the lower range. Lutron has said they have not been able to make a dimmer that will dim a CFL properly. Now I guess you can try them and as long as they don't dim them to the lowest range they may work fine.

Why can you not use larger than 45 watts? You live in Calif.?

 

[LarryFine]

I noticed that at their other office, in some rooms that they have removed the lamps from the cans, because it was too bright in the room.

. . . I can only put a 45 watt incandescent lamp in the fixture to meet energy code.

What's the watts of the too-bright bulbs they've been removing?

 

[Lcdrwalker]

The one time I dimmed CFLs, they shifted to the red as they were dimmed. I've had good luck with LV MR16.

 

[DanZ]

Dan there are some CFL's that say they are dimmable but they do not appear to work in the lower range. Lutron has said they have not been able to make a dimmer that will dim a CFL properly. Now I guess you can try them and as long as they don't dim them to the lowest range they may work fine.

Why can you not use larger than 45 watts? You live in Calif.?

I think at least one of the doctors working there wants them in the lower range. If it weren't for that, I would use CFLs. But, I've heard (from this forum, actually) that they don't work as well as incandescents on a dimmer.

There's 4 or 5 doctors in this office, and they all use different light levels, some like it bright, some like it dim.

What's the watts of the too-bright bulbs they've been removing?

I'm not absolutely sure, but I'm guessing 100 watts. They looked like flood lights in the can, and a couple of the treatment rooms were rather bright with only four cans.

The one time I dimmed CFLs, they shifted to the red as they were dimmed. I've had good luck with LV MR16.

I've never heard of them turning red, that's a new one! I'll have to look into the MR16.

Not to get off on a tangent, but does anyone else feel that the light levels allowed by ASHRAE 90.1 (2004 is what Ohio is on at the moment) are way too low?

 

[electricmanscott]

You can NOT legally dim a CF lamp.

 

[Dennis Alwon]

You can NOT legally dim a CF lamp.

And you base that on what? Never heard that before but I never use CFL's anyway- just curious

 

[iwire]

And you base that on what?

I am not sure what Scott has in mind but I will go with 404.14(E).

 

[Dennis Alwon]

I am not sure what Scott has in mind but I will go with 404.14(E).

Thanks, and Lutron does not list any of their dimmers for CFL's as far as I know.

 

[iwire]

Thanks, and Lutron does not list any of their dimmers for CFL's as far as I know.

They do have CFL dimmers, just they are not the dimmers used with Edison base incandescent fixtures.

Here at the forum it seems when we say 'CFL' we are specifically talking about edison base CFLs used in incandesent fixtures.

Howver CFLs also come with plug in bases that go in floursesnt fixtures.

These are dimable if the fixture was ordered with a dimable ballast and the correct dimmer to work with that ballast.

Typically we install dimmers on these plug in CFLs fluorescent in office building conference rooms.

 

[Dennis Alwon]

These are dimable if the fixture was ordered with a dimmable ballast

These I know about but I thought they were called PLC fluorescent lamps

 

[iwire]

Both are CFLs. :smile:

Here is Sylvania's catalog of CFLs, notice on the left there are 'Pin Based' and 'Screw Based'

http://ecom.mysylvania.com/sylvaniab2c/b2c/z_login.do

 

[Dennis Alwon]

Both are CFLs. :smile:

Here is Sylvania's catalog of CFLs, notice on the left there are 'Pin Based' and 'Screw Based'

http://ecom.mysylvania.com/sylvaniab2c/b2c/z_login.do

I realize they are both CFL but I have always heard of the pin CFL's referred to as PLC. Apparently it refers to the size see below.

BTW-- it appears you can now copy and paste info from web pages with pictures-- see below.

PLC26W/41K/G24D-3/2Pin - SUPRA LIFE

Back to List

$5.49 Each

SKU:
P81804

Size:
PLC

Base:
G24D-3

Watts:
26

Hours/Color:
12,000/4100K

Case Quantity:
25

MOL:
7.625''

Qty:

 

[iwire]

Dennis yes PLC is in the base designation of some of those lamp from some manafacturers but still they are all "Compact Fluorescent Lamps" (CFLs)

Much like there are many types of incandescent lamps. Mogul base, Edison base, intermediate base, candelabra base etc.

So we can go on but the fact is offically 'CFL' refers to a who family of lamp products.

Check this one out, no 'PLC' but it is still a CFL

CF18DT/E/827/ECO

 

[Dennis Alwon]

Check this one out, no 'PLC' but it is still a CFL

Okay. Got it now. Thanks.

 

[electricmanscott]

I was referring to screw in type and dimmer compatibility, or lack of.

 

[DanZ]

So, these

DIMMABLE 24 WATT MINI SPIRAL COMPACT FLUORESCENT

18 WATT SPIRAL DIMMABLE CFL/27K SUPRA LIFE COMPACT FLUORESCENT

WESTINGHOUSE R20 DIMMABLE COMPACT FLUORESCENT

can't be legally dimmed?!?

 

[Dennis Alwon]

Actually Lutron makes a dimmer for CFL screw in types.
Here is a statement from there site
Screw-in CFL bulbs are energy efficient and have the longest life. However, they provide less pleasing light, start up slowly, may flicker, and are not disposable. Most dim poorly, although Lutron offers dimmers for the Philips Energy Saver dimmable CFL.


Lutron CFL Dimmer

 

[iwire]

I don't see anyway to dim those Edison base lamps and comply with 404.14(E).

 

[iwire]

Actually Lutron makes a dimmer for CFL screw in types.

It is not for all screw in CFLs, only tor three specific Phillips lamp models.