fluorescent house lighting advice

[byronyasgur]

Hi - our church is currently in the middle of interior building work on the new building which we'll be soon moving into. Originally the room had fluorescent lamps in it ( i think there were around 12 or 15 maybe. ) the room in question is about 12m by 15m and the ceiling is a bit convoluted but basically ranges from 3m at the back to 4m to the front over the stage area. We are on a tight budget so the plan was to reinstall these same fluorescents with new diffusion covers after the building work was completed, and that would be fine but for the fact that we are also putting in some lights over the stage and have now realized that the house fluorescents will not be dimmable and so will overpower the stage lights ( and anyway we dont want to have the hall 100% bright during worship if possible) ( neither do we want to simply turn them off .... and i dont think it will be possible in any way to prevent them from flooding the stage because of our arrangement ) .... so we need something that's dimmable ....... so i suppose we must replace the fluorescent tubes with something , but what ? ....... incandescent? led? halogen? or is it possible to get a fluorescent dimmer - i have seen them on the net but they seem a bit hard to get and info a bit scant ..... can we get them in ireland, and are they reliable, and would they dim typical fluorescent tubes or would we be replacing the tubes too .... (sorry about all the questions but i would genuinely appreciate any help possible because i am not that knowledgable and i got handed this problem and currently the building work is in danger of stopping because the electrician needs to know where to run cables before the builder continues slabbing work ) .... sorry if that's too much info

Other than that .... are we limited to incandescent .... these would in theory be my first choice from a light point of view BUT i dont want to use incandescent if possible because a) the bulbs blow much more often than fluorescent b) they use a lot more power than fluorescent c) i think theres a ban coming in on incandescent bulbs ( not sure of the details on this) ....... but the only other option seems LED which sounds great ... but isnt that *really* expensive ( remember the budget for replacing the house lights was the cost of 12 or 15 diffusers - about 2 or 3 hundred euro i suppose ... im sure it's a lot more now but still the less it ends up the better ) .... we dont own the building either .... it's a 10 year lease so a 20 year payback is not that interesting

also ..... i have tried to look up dimmable cft or halogen but im not that sure about them ... also i have heard of t25 theatre lighting but again i cant seem to find out much about it

any help greatly appreciated - to sum up im basically the cheapest dimmable option in the 5 to 10 year period taking into account the possible ban on incandescent bulbs ( i cant post the link but it;s on wikipedia)

[zactommo]

We are about to install new dimmable fluro's in our building.

We choose them for the same reasons as you mentioned above
1) Long term running costs (both power consumption & bulb life)
2) Incoming bans in incandescent fixtures
3) Ease of installation (we're doing a 1 to 1 swap for our current fixtures
4) Available power. Our current system probably couldn't handle running incandescent in both the stage lighting & house.

They are reasonably common place, and any good lighting consultant should be able to give you information on them.

In terms of dimming, they work a bit differently to incandescent fixtures. They have a ballast as part of the fixture, which controls the light. Instead of dimming via lowering the AC current to the fixture, the lights are sent a 10v DC control signal, which tells the ballast how much to dim the lights. 10v being full brightness, 0v being off. They can be dimmed by a simple rheostat on the wall, which is simple and cheap, or you can purchase converters which allow you to interface the lights with a DMX system, which is what we will be doing in our new setup.

As to whether you can keep the current fixtures, my understanding would be, theoretically that you can just replace the ballast in each fixture, which would allow them to be dimmed, but i'm not an electrician. The best move would be to contact a large electrical wholesaler in your area, and talk to them about what you want to do, and they'll probably have a lighting designer who can talk to you about the options. They should do it for free, and i'd probably get multiple opinions.

[streamkoinonia]

We have our house lights (florescent) set up through the lighting board, but can only get them to dim so much. It's a compromise, but can work.

Shawn
ministryfx.net

[D.R.HADDOCK]

Floros are dimmable, but require modifications to the wiring, and possibly new ballasts
But dimmed floros do have some problems, such a flicker and not smooth dimming,
If you are considering using incandesant, I have used T25s in our house lighting,
thus far it has worked well. T25 and base mounted in standard industrial type high bay fitting.
But can be put in other types of fittings if you wish.
If you paste this into your browser -
http://www.freshwatercc.qld.edu.au/g...YyMWYyNTdkNGVh

you can see them.
sorry its not the best picture, but its the only one that shows them.
T25 lamps are cheap and high in output,
so work well,
I rarely need to run them at full output,
so they last well. around 18 months.
Leds show promise,
but are still too expensive for most.

[avchum]

We currently use 100watt halogens in par 38 cans, 43 of them. Considered a switch to dimmable CFL's, but can't locate dimmer switches. Currently using pre-1995 Lutron 1000watt and 2000watt dimmers. Would like to use the CFL's if appropriate dimmers are available. Looked into dimmable LED's also, but told the cost for a 24watt LED replacement was in the neighborhood of $125 each. At that rate the payoff on power savings would be in excess of 15 years. Any suggestions? I know most of the posts on dimmables are at least a year old.

[jthtiger]

Originally Posted by avchum

but told the cost for a 24watt LED replacement was in the neighborhood of $125 each. At that rate the payoff on power savings would be in excess of 15 years.

But of course if you look at the lifetime of an LED bulb, that number is pretty negligible. LED's are usually rated at either 50,000 or 100,000 hours. At this rate, if you left them on 24 hours a day, 7 days a week, you wouldn't be changing the bulb for about 6 years (for a 50,000 hr bulb). If you have them on 10 hours a day 7 days a week, that number increases to close to 14 years. I don't know of anyone who leaves their house lights on that long.

-Tyler Herron

[[Admin] osborn4]

I'm looking forward to LEDs becoming more and more affordable. Some year, CFLs will only be a bad memory.

[Esoteric]

Keep in mind that there are no dimmable LED lamps out there. To get full dimming you must buy a complete fixture.

Mike

[zactommo]

Originally Posted by avchum

Considered a switch to dimmable CFL's, but can't locate dimmer switches.

The dimming with fluros happens internally as part of the ballasts function, so you don't need external dimmers. The light outputs a +10v control signal, and then you can modify that signal, and return it to the light to get your dimming. So if the full 10v comes back to light, you get full power. If you send 5v back, then you get 50% dimming, and so on and so forth.

There have been a few delays in us getting out system in. Hope to get it done by the middle of January, so I'll post some pics/tutorial of what we've done once its done.

[RickR]

Originally Posted by zactommo

Originally Posted by avchum
Considered a switch to dimmable CFLs, but can't locate dimmer switches.

The dimming with fluros happens internally as part of the ballasts function, so you don't need external dimmers. The light outputs a +10v control signal, and then you can modify that signal, and return it to the light to get your dimming. So if the full 10v comes back to light, you get full power. If you send 5v back, then you get 50% dimming, and so on and so forth.

There have been a few delays in us getting out system in. Hope to get it done by the middle of January, so I'll post some pics/tutorial of what we've done once its done.

• CFL dimmers not only exist, but there are now specialized "wallbox" types just for CFLs. Unfortunately they don't work much better than older types. You still need dimmable ballasts!
• Some ballasts function as you say but there are several other methods as well. Including ballasts that can dim from standard dimmers, generally called "two wire" systems.
• There are dimmable LED replacement lamps. Generally they are very low output and still way too expensive for most folks.
• Most church sanctuaries aren't used for enough hours for energy retrofits to pay back very quickly.

My suggestion is to look at a dual system. FL- not dimmed for daily use. INC- on dimmers for services. Best of both worlds with only a slight increase in installation costs.

FWIW - My prediction is that we will have good LED replacements in the next 1-3 years. The highest output types will be the slowest to come around.

[millamber]

Originally Posted by Esoteric

Keep in mind that there are no dimmable LED lamps out there. To get full dimming you must buy a complete fixture.

Mike

*Ahem* http://www.acclaimlighting.com/#/acc...-30/4538182745

Off topic totally, I know, but wasn't sure if you had seen some of the dimmable LED products out there now.

[Esoteric]

Originally Posted by millamber

*Ahem* http://www.acclaimlighting.com/#/acc...-30/4538182745

Off topic totally, I know, but wasn't sure if you had seen some of the dimmable LED products out there now.

You missed the last part of my post. There are no FULLY dimmable LED lamps out there. Just to clarify in order to build up the amount of resistance to be compatible with standard dimming, those units are made with LEDs wired in series. Thus at some point the power supplied is insufficient to power the lamp and the LEDs shut off. Usually at the 20% threshold (there are some that will make it to 15% though). Also the dimming curves on these lamps are just awful.

Right now if you are going to use LED house lights the only options are fully enclosed fixtures. We have done several specs with these units, but the energy savings was such that it would take 10-15 years before the client sees a ROI. They did find that an acceptable ROI.

I am familiar with probably 99% of LED products out there.

Mike