High pressure sodium HID lamp info - closeup pics added

[Zelandeth]

Well, it's a HID lamp as far as I know anyway. Found this getting chucked out of a local warehouse when they renovated the place, and me being the lighting fanatic I am, I grabbed it. 250W SON-T High Pressure Sodium warehouse lamp, made in England by Fitzgerald Lighting. Sure there's a model number someplace, but I sure can't find it.

Ballast is made by Philips, and has the following number stamped on it, which I believe to be a model number.

BSN 250L 34
9136 251 605

Ignitor, also Philips, appears to be of the SN58 type.

Lamp is also a genuine Philips 250W SON-T unit, rather than a cheaper replacement.

Basically, once I got it home (carrying it, on foot for over two miles, then on a bus for two hours...the darn thing was getting heavy, I set to work cleaning it - was disgistingly dirty. Only one back together did I actually decide to see it it worked. DOES IT EVER! Initially, it only gives out a blueish white light, about the same as a 30W flourescent tube. Leave it for about ten minutes, and it goes through three phases, blue-white, bright orange, yellow, then settles into its normal running pale yellow/white...at an unbelievable brightness level. A real shame that I only have it sitting in the corner of the room as an interesting item, really should be able to think of a use for a light that bright. Well, sure I'll think of something.

Until I got hold of this, I'd never really thought about this type of light. I've got a 250W incandescent halogen lamp in the light shining onto our driveway, and a 500W over the back garden, and the light output from the 500 doesn't even come close to this thing halfway through warmup.

What I want to know, it how much more efficient are these lamps actually? I don't have the equipment to measure luminousity/intensity or anything like that, but I assume that someone else may have a similar lamp and that equipment, and could look into it. This serves no purpose whatsoever, other than satisfying my curiousity.

I might try to get some pics of the now cleaned, polished (and in darn good condition actually) beast idle, during the warmup phases, and at full power, might try to catch the tube when cooling down, which looks pretty cool...er...well, red-orange hot actually.

Another small query, given that most folks here seem to havea fair selection of mainsream and more unusual lights, how common are these things to be found by the private user? Have I for once in my life got lucky and found something rare?

Zel.

[Daniel Ramsey]

I mounted a 400 watt HPS atop a 35' cement silo for illuminating our batching facility, because of the orange color it travels longer though appearing dimmer than a Metal Halide that is near to perfect for repairs/inspections inside our maintenance building.
More often its the prime choice for street lighting here in the US replacing earlier Mercury Vapor lamps that were used but are energy inefficient, the High Pressure Sodium (HPS) is very cost effective in the long run.
The HPS is very efficient, roughly it uses 1/4 the wattage for same amount of lumens output vs. a Mercury Vapor.
Be careful what position it is when on unless it says "universal mounting" on it.
The HPS is best for hiway,street and yard illumination over large areas. The normal pricing of a HPS is also 2-3 times more than a MV or MH lamp.

You got a great deal there, beware those bulbs can be pricey if it goes out but normally its the capacitor that pops first, also it uses high voltage during startup, make sure its grounded and all connections inside are rated for minimum 105c temperature.

[INRETECH]

HPS is bascially the most eff light you use
Although, some people are turned off by its slightly "pink" glow

The process of making light in the HPS is one of the very few that is non-destructive; that is during the generation of light - no elements are being used up; in short - the light will run forever

The only expendable in the light, is one of the gasses used in the starting phase of the light

Although they are bright, they do not like to be dimmed; I worked at a lighting company for 11yrs and had a 1000w bulb running on the desk next to me when I first started

[Chris M.]

Nice find, sir!

-

Low Pressure Sodium is the most efficient electrical lighting source out there. They are the yellow/orange ones you see out illuminating roads, though they are getting less common unfortunately. Amusingly I have one of these up here in the room, and warm it up now and then if I need some extra light! Everything turns a monocrhromatic amber colour, but it`s kind of unique.

High pressure sodium light fixtures can be bought by everyday folks here these days, but they are not too common and are usually only 70 watt fixtures. Sold as security lights to be left on during the hours of darkness, as the wattage os so low they`re cheap to run. But most people don`t like the fact that they take so long to warm up, favoring something that goes *on* the moment you want it, not when it wants to [img]images/icons/grin.gif[/img] They`re also not so fond of the orange colour. Still, you see`em here and there.

Indoors? Only marijuana growers and oddball lighting enthusiasts (I am *not* the former, but openly admit to being the latter) would have them indoors. Because of the warm-up time and the odd colour again. Metal Halide lighting (cold bluye/white colour, almost identical control gear) may be stumbled into now and then, but it suffers the same warmup delay as SON, and a high price for fixtures and lamps as an added bonus.

-

Luminous efficiacy for these lamps can be found on Don Klipstein`s site somewhere, and also the excellent http://lamptech.co.uk should have some info on them too. I unfortunately can`t remember these figures offhand.

[img]images/icons/rolleyes.gif[/img] [img]images/icons/wink.gif[/img]

[Zelandeth]

Hmm, interesting idea that the use as a security light. Would have to stay inside the bedroom window as it's not sealed in any way against the elements, and the idea of water getting into the unit with this kind of starup and running voltage doesn't bear thinking about.

Thanks for the advice on checking wiring/orientation. Wiring I checked when I inspected the unit before I first fired it up, all good. As for the orientation, nothing has a "top" marking on, and is all securely mounted to the chassis, and nothing gets hot in there even after it's been running for some time. The tube is the only thing I can see being sensitive to orientation then, as the ceramic part gets so hot, if it was run in a vertical orientation, one end would get hotter than the other - so it doesn't get run vertically. Lamp's usually on its side when run, that also ensures that all the vents are clear. This has hooks on the back of the unit which chains would have hooked onto, as the unit was originally suspended from the ceiling of the workshop. Therefore, the lamp is in the same orientation as originally the way I use it.

As for warmup times, I just positioned a photocell in front of the unit (80mm from the tube, as close as I could get it), and switched it on. After 4:56, the ammeter reading stopped rising.

Not sure if the photocell could actually be used to fond the lumunous value. Current levelled out at a steady 4.39mA (I left the lamp running for a further 10 minutes to make sure that it was actually up to full temperature). The same distance from a 60W clear incandescent gives 0.87mA, and a 100W ??? (Couldn't find one...will get value when I can find one), 150W 1.48mA. Don't know if someone can use these figures and actually work out some sort of value for the luminousity from them (i.e. a known value for the 60/100/150 and extrapolating.) 1000W HPS lamp...now that would be something to see...just have to remember my sunglasses, which were necessary most of the time when getting those current values (blackout shades like those used for viewing solar eclipses are also handy).

There are a lot of LPS lamps still used in street lighting here, and I'd really like to get hold of one - to complete the set so to speak, would eb nice to have both a LPS and HPS lamp. As they're more often weatherproof, I could actually use it outside to illuminate the driveway. Now, they do have an interesing colour during startup. The times this gets used usually include if I'm working inside the PC or soldering small components, as it's so darn bright that shadows suddenly stop being an issue, and I can see what I'm doing. Only thing I see as a drawback is the 50Hz flicker from the mains frequency. Cats seem to have decided that it's an excellent substitute for the sun during the evening too - both ended up curled up in front of it this evening.

Lamps don't seem to be overly expensive for this, I bought a replacement lamp from a builder's merchants not long ago, as the ends of the tube here are slightly blackened (I assumed that this was a sign of tube aging, like with normal flourescents), and I usually work on the basis of "if it's unusual, and I see one, get it in case I need it" only cost me £9.75 ($13.75 USD), which I didn't see as being too bad. Apparently the tube blackening means nothing, as light output seems to be near identical.

Forgot to mention the actual visual appearance last time, white painted metal case (steel as far as I can tell), 590mm (23 inches) long, 290mm (11.5 inches) wide, 180mm (7 inches) deep, not including mounting braket (240mm 9.5 inches with the braket), light area is 380mm by 260, and the reflector has a "bubbled" texture, and is covered by a wire grill...which took me a good 20 mins to figure out how to remove. Panel below the lamp area itself slides off to allow access to the electronics. Lamp fitting appears to be a standard ES screw thread. Though it could be a slightly larger in diameter, haven't got anything to compare to though.

Now, had I rambled on like this anywhere else, I'd have expected to be flooded with people trying to shut me, up, but I don't think I need to worry too much about that here - nice to find somewhere where people actually share my obsession with unusual lighting devices.

Zel.

[Zelandeth]

This is a picture of the unit. It's sitting on the end there, rather than orientaited how it is when in use. Just has to be like that to fit neatly out of the way in the room. Will try to get some better pics tomorrow. Excuse the quality - very cheap, very small camera.

[Nerd]

can take some close up pics?

[LEDagent]

should there be any safety concerns...other than heat? Like explosions and what not. Aren't these type of bulbs under very high pressure? If they are...i wouldn't want to jar the unit around while it's on. A regular bulb that pops is bad enoegh...

How hot do one of these units get anyway?

[Zelandeth]

I'll try to get some close pic tomorrow.

The inner tube of the bulb is under high pressure, but it's inside the outer envelope as well. I try to leave the unit to itself as much as possible when in operation (or ever) for that very reason. Don't want the tube to explode, or to break it.

As for heat, the case gets hot to the touch, but not unbearably so. The inner tube however gets insanely hot. When switched off, it can be seen glowing white hot, and taking a good 90 seconds or so before the heat drops to the point that the ceramic stops glowing. Another reason I guess that the inner tube is a trasclucent ceramic material rather than everyday glass - apart from the fact that various sodium compounds attack glass if I remember correctly.

[Chris M.]

I guess that the inner tube is a trasclucent ceramic material rather than everyday glass...

Translucent Aluminum Oxide to be precise. Yes, that Aluminum. Affectionately known as Lucalox in the trade, and I believe that term is used as a brand name too.

[img]images/icons/grin.gif[/img]

[James S]

"Transparent Aluminum?"

"thats the ticket laddy! Whats it worth to you? Or should I just punch up clear?"

[Chris M.]

Good ol` Star Trek [img]images/icons/grin.gif[/img] Who would`a thunk it`d come true one day?

There`s hope for the Deep Space program yet....keep working on that warp drive guys......

[img]images/icons/tongue.gif[/img]

[Zelandeth]

Right, here are the requested closeup pics. Again, excuse the quality. Problems are more pronounced as the image in the viewfinder of the camera has absolutely nothing to do with what the image taken is.

The case sitting on its side. This is normally the orientation it's run in (Though not on the bed of course!) as the tube is then in the correct orientation, and the ballast isn't sensitive to which way round it is.



The case from another angle. You can see from these two pics the excellent overall condition of the unit.



A seemingly futile attempt to capture an image of the reflector's "bubbled" texture. The camera didn't really want to co operate, but I think it is at least vaguely visible. I might try different lighting conditions and try again.



...And One I took a few minutes later with more success.



Simple close up of the electronics, which I've termed the "Ballast compartment" No amount of shining lights into there or changing angles seemed to be able to clear this up.



Me holding the tube in one hand, and the camera in the other. Trying to photograph something that's primarily transparent is an amusing task.



The tube sitting next to my keyboard (Standard size, 104 key.) to give some sense of scale. Tube is approx 245mm from the solder blob on the base to the end of the outer envelope, diameter of 40mm. Inner tube is roughly 85mm by 7mm.



Detail shot of the almost standard looking screw fitting. Was going to put a 150W incandescent bulb next to it for comparison, but after waiting 5 minutes for that to cool, got impatient.



>>Continued in next post...

[Zelandeth]

Hope these pics were what you wanted. If you want to see anything else there, just ask. Operational pics are near impossible for me, as the intensity of the light simply overloads my camera (Quite spectacularly). - as shown below. The black bit in there is actually the light emitting part of the tube.



Also, found the info panel about 20 seconds ago. Model is LB250SON...which I've been hunting for ages to find. Was actually underneath the mounting bracket at the back.

[Don Klipstein Jr.]

A bit on HPS lamp pressure and wear mechanisms and efficiency:

The pressure in the arc tube is normally less than atmospheric pressure. The active ingredients in an arc tube can be at a pressure less than atmospheric and the lamp can still be called a high pressure lamp. If you have the arc core gas/vapor temperature closer to the arc core electron temperature (there is such a thing) than to the container temperature, then the lamp is a high pressure lamp rather than a low pressure one.

In fact, if the arc tube ruptures, the outer bulb usually does not break.

As for wear mechanisms: The thermionic coating on the electrodes wears out, amd more rapidly during starting than during steady operation - same as mercury and fluorescent lamps.
Another thing is that the arc tubes do slightly react with and/or leak out sodium during operation, so there is a surplus of sodium in them. Normally the electrodes wear out before the sodium runs out. Sometimes there is still plenty of sodium and some useful life in the electrodes when the regions of the arc tube discolor enough from electrode sputtering to absorb enough light to increase the amalgam reservoir temperature to vaporize enough excess sodium to make the arc's electrical characteristics such that the ballast cannot sustain the arc, but usually "end-of-life cycling" does not occur until the electrodes are dying.

Luminous efficacy of high pressure sodium lamps is a little over twice that of mercury lamps of similar wattage.

- Don Klipstein (don@misty.com, http://www.misty.com/~don/index.html

[Zelandeth]

Thanks for the info there Don. Incidentally, nearly everything I know about these lamps so far is thanks to what I read on your site a while back, and what I've been told here.

Have to admit though, that the gas pressure being below atmospheric pressure was news to me.

The old tube in this lamp died that way, would start perfectly, warm up, then after about 5 mins, would shut down, cool down, restart...repeat. One outside at our local bus station's been doing that for ages as well...irritaits me every day when I walk past it...why don't they just change the darn tube!

Think it's worth asking you whether (other than the obvious things such as overheating and the high voltages concerned) there's anything I should watch for when using this thing.

Thanks again,

Zel.

[INRETECH]

There are two gasses inside the bulb, the gasses that make the light are combined and then generate light - they last forever

But, the second set of gasses is used during the starting phase of the bulb, and is "used up" during this phase; so simply put - the light lasts forever, but has a limited number of starts

My first days at my lighting job, we all had to wear sunglasses since they were doing testing on the 1000w fixtures

[Occultican Axsave]

I've found some information on the SON-T bulb from our database:

OVERALL LENGTH 257.00 mm
BULB DIAMETER 47.00 mm
LIGHT OUTPUT RATING 27500.000 LUMENS NOMINAL
AVERAGE LIFE RATING IN HOURS 28500.0
EMITTED LIGHT CHARACTERISTIC WHITE
LIGHT CENTRE LENGTH 158.00 MM
VOLTAGE RATING NOT RATED
WATTAGE RATING 250.000 WATTS
CAP (BASE) STYLE RDG A A2A6 E40 (GES)
BULB STYLE RDG B B25 TS (TUBULAR)
BULB LIGHT TRANSMISSION TRANSPARENT

Axsave

[CanadianGuy]

What great info guys. Thank you. I get a kick out of people who think that cycling of these lights is "normal" operation, and that they are just "cooling down." Hahahaha.....I am blown away at how much stuff there is to know about these lights, and how many of you know this stuff. One question...How good would one of these lights run off of a gas generator? My Dad's cottage doesn't have service, so we use a generator. Although, I think I'd rather have a good flashlight to wander around outside, rather than all that light pollution drowning out the beautiful night sky. See ya

[CanadianGuy]

Oops, silly me...this is an old message. Sorry

[LED-FX]

Old message given new life thanks to the latest threads feature :-)

The fixture Zelandeth has pictured is what is known as a low bay fitting for lower roof heights in loading bays etc.

High bay fittings burn the lamp vertical with a parabolic/spherical reflector like a lamp shade, used in big warehouses etc.

Guess you`ve had a look at Mr Don Klipstein`s site, the bible of lamp tech on the net.

Main thing to look out with ballasted fittings on generators is Power Factor, watts are not quite watts with inductive loads as seen by the generator. 100W may appear more like 130W to the generator because of the inductors in the ballast.

Good fitings have a Power Factor Correction capacitor, PFC, fitted which drags the PF back substanially. Cheap ones shave the couple of bucks off by leaving it out.

High Pressure sodium, SON lamps, are not a colour to everyones taste but hugely efficient and give some colour rendering compared to Low Pressure Sodium, SOX, which are the monochromatic orangey yellow.

Strangely astronomers would prefer SOX streetlighting as it is simple to filter out the light in their telescopes.
But out in the country lot to be said for a genuinely dark sky, not the death of night yet.

http://www.geocities.com/an_focal_sc...n/summary.html

Adam

[PsycoBob[Q2]]

As a minor note, It seems that most arc lights don't like running off modified-sine inverters. Some lights work (while making unusual noises) while others refuse to start. True-sine inverters and normal AC generators work fine, however.

[Zelandeth]

Just thinking there, there are a couple of things that I'm looking out for just now, and think that this might be a reasonably appropriate place to ask.

I'm looking for an LPS fixture and tube - wattage isn't really an issue, as it's more to "complete the set" so to speak...and because I've all but forgotten that funky warmup colour because there ain't any left around us (Town recently replaced them with mercury vapour lamps (I think, off the top of my head) which make things look really wierd...like moonlight but a few hundred times brighter...I liked the amber better!!!

Another thing, for curiousity's sake again. OLD style flourescent fixture, with the manual starter switch. Any ideas of where to look Don?