Lighting

You can always try this link. They do a very good job of searching for technical material. Incandescent bulbs are less efficient than halogen bulbs so that will not be helpful. The most efficient non-new technology lamps are fluorescent but you've eliminated this possibility already. So you might investigate LED technology for it does turn on very quickly. But this is a new technology so you might find some hidden draw backs.

Dear Redfred,

Thanks for your reply,

The area where we are planning is a furnace area (Ambient temperature high), I thought that LED flood lights does not with stand this temerature.

Well if you look at your original posting you'll notice you mentioned nothing about a furnace area. That's a cheap shot. If you're not going to tell us all of the pertinent conditions, then do your job yourself.

LED are going to be of much higher efficiency (hence less KW) buy much more higher $s. And also the level of illumination, as on date are not upto the order.

Try for metal halides and others. There are instant start metal halides. But the saving finally may not be too high in Watts since the efficiency difference may max save a few hundred watts at max. What you need is the lux and that can not be compromised from safety angle.

I have a desk lamp using a efficient bulb 100W Fluorescent really 23W and it is "instant" turn on/off. It is a spiral shape and no turn on delay whatsoever and very white light. Made by OptoLight 1650 Lumens Energy Star (10) will give you 1000W but you will only burn 230W.

Check for efficiency comparisons

http://www.cfa.harvard.edu/nelpag/INFO52.html

In film they say, "A light without barndoors, is not a light." Certainly the Lamp is only one component of a light. The control and quality of light comes from essentially the housing, properly mated to the source.

The housing of the lamp for movie lights, Hotlights is partly designed to prevent overheating of the lamp. Typically many film projectors incorporated fans, as do many computers to maintain an operating temp.

Possibly it may turn out that the LEDs in your case need to be protected from external heat, instead of from the heat they generate, which is different from the normal case.

Hence you may be in the position of determining what light source is preferred first, and then what sort of housing to put it in for the conditions.

P.S. In film and tv lighting it is not that uncommon at all to essentially build a light in a way similar to the way one might build a speaker cabinet for a particular type of audio speaker.

Look into induction lamps. Typically, the cut energy costs on half in cases like yours. They may not come large enough for a one-for-one replacement of 1000watt halogen. These can restart instantly so you can employ motion sensors for additional savings. Be careful of the cheap Chinese made lamps. Induction lamps also have a long life, 8-10 years depending on the usage. They certainly are going to be a more expensive solution but when you factor in maintenance savings along with the energy, the project is usually worthwhile. We have been working with a large steel manufacturer and have converted all there HID fixtures to induction. So, temperature should not be an issue. However, if it is, you can install some Big Ass Fans www.bigassfans.com. Essentially, these are low speed, high volume fans. Temperature gradients from floor to roof can be large in production facilities. These can even those temperatures out.

Hi ambarasu,

Can you please confirm the size of the 'furnace' the intended lighting is to be used?

A 'Furnace' can mean anything from a very small brick hearth to a Bessemer container!

As redfred has said, we must have all pertinent details to try and give full and accurate advice.

Take care.

Sorry I don't agree.

You say these lamps are used for immediate lighting after a black-out, and only in certain areas. So I assume the normal lighting is more energy efficient, like metal halide. So these 1000W lamps are only used for the few minutes it takes for the main lighting to strike up after a black-out.

The wattage may be high, but the total energy consumed is insignificant, especially when compared to the normal lighting running all day. Installing energy efficient lighting for these few minutes is non-sensical.

By the by, halogen lamps survive high temperatures very well, so are well suited to the emergency situation you describe. Fluorescent do not take kindly to either high or low temperatures, and must be derated accordingly. LEDs positively hate heat, and a lot of the current development work is aimed at getting the heat away from the source.

Metal halide hi-bays and lo-bays are available with auxiliary halogen lamps, for just this purpose. In this instance they are fit and forget, as the internal circuitry cuts the halogen out when the halide is up and running.

If its a safety issue and the outage is short duration, you could back some metal halide lamps with a UPS (obviously kept somewhere cooler). I've done this in cold stores. This will give a few minutes until your genset kicks in (I assume you have a genset to cope with all these black-outs....).

Hello BG,

I pretty much agree with what you said. As the OP has not gotten back yet with more details of exactly what the area to be lit is like, size and safety-wise, I guess we will have to wait for a reply.

If, as a for instance, this refers to to a large steel making furnace I doubt this question would have been asked anyway? If however, it refers to a very small area where a single gas flame powered furnace of just a few inches or feet across, again I can see no need to worry. Just pick up where you left off, when the power resumes?

Take care.

Hi friends,

Its is Glass making furnace

size will be around - 20 Mtr X 10 Mtr & Height 5 Mtr,

Ambient temperature around the furnace will be around 60 *C.

These fittings shall be provided in the sides of the furnace.

Hello ambarasu,

Thanks for the reply post.

But it would have saved a whole lot of time and 'blind searching' if you had mentioned these details in the first post. No insult intended, OK?

How often and for how long does your lighting go off?

You have some good answers already, but I would have thought a single medium to narrow Spotlight for each working area would be adequate? If the total area is only 20 Metres x 10 Metres (~65' x 33') The actual 'working area' will be about 7m x 7m (~ 23' x 23')?

Of course this is an estimate of the working area size. The area size and the length the lighting power is off, and whether it is a regular daily/weekly occurrence will also have to be considered when choosing either the type of temporary lamp or lighting, or the answer to the regular cut-outs, which could perhaps be a small generator? Or a couple of batteries which is part of an UPS System, or, perhaps more likely a direct link and hand operated switch to three or four large batteries, which will power the temporary lamps, not the main Factory lights.

No doubt the other contributors on this thread will be able to give a better perhaps more detailed answer to what seems to be a pretty small lighting need? There does not need to be any lights near or high above the furnace. The furnace can be lit from a wide spot light comparatively low down so it is not effected by any heat. Though I do not see this as a problem.

Good luck and read the other posts which have a lot of detail.

what is the ambient temperature around the furnace? The induction lamps work from -25 to +45 deg C. They have 100,000 hour lamp life, no flickering or strobing. Operational voltage 100-277 volts instant start-instant restrike. Induction lighting systems are made up of three main parts a high freqency ballast, an induction coil and a discharge bulb. The lamps have a rendering index of RA80+ with a colour temperature of 4100k. The highest wattage I have seen used is 200W. The are brighter than your standard metal halide lamp though. We have run lux level tests on these.