Author Topic: 50,000 hr + 35 watt hps?  (Read 2808 times)
wide-lite 1000
Member
*****
Offline

Gender: Male
View Posts
View Gallery


50,000 hr + 35 watt hps? « on: November 27, 2018, 10:18:27 PM » Author: wide-lite 1000
My question involves a Phillips 35 watt hps lamp used dusk to dawn lighting my driveway. This bulb is currently on it's second fixture. The original light was a regent wall pack, the current one is a RAB area light jr. I personally installed this thing in spring of 2001 (original fixture has manufacture date of 10/16/00)  Is this normal for these low watt hps's? Assuming approx. 10 hr per night x over 17 yrs = over 60,000 hrs. Years ago I bought 3 extra lamps for a closing hardware store for $1 each and at this rate i'll be dead before I use them all!  WILL IT EVER DIE???
Logged

Collector,Hoarder,Pack-rat! Clear mercury Rules!!

BlueHalide
Member
*****
Offline

View Posts
View Gallery

Re: 50,000 hr + 35 watt hps? « Reply #1 on: November 29, 2018, 12:17:21 AM » Author: BlueHalide
That is not normal, I typically get 15K-20K hours from major brand (GE, Philips, Osram) 35w and 50w HPS lamps, typical dusk-to-dawn fixture relamping is every 4-5 years for those lower wattage lamps. 60K hours is unbelievable, are you certain its the same lamp from 2001?
Logged
RyanF40T12
Member
*****
Offline

Gender: Male
View Posts
View Gallery

Re: 50,000 hr + 35 watt hps? « Reply #2 on: November 29, 2018, 01:06:55 AM » Author: RyanF40T12
every once in awhile you'll get one that will last.  Sometimes it's being underdriven a bit.  But I've also generally found that those bulbs that do last that long generally kill the ballast in the process. 
Logged

The more you hate the LED movement, the stronger it becomes.

Medved
Member
*****
Offline

Gender: Male
View Posts
View Gallery

Re: 50,000 hr + 35 watt hps? « Reply #3 on: November 29, 2018, 04:18:03 AM » Author: Medved
One could ask a question whether this lamp ever performed as it should, so if e.g. it is not running too cold e.g due to gas in the outer.

There were a few cases in the history with lamps lasting unusually long (however these I know were incandescents), but they had one in common: These are/were defective from the start, as neither of them ever delivered the light they were supposed to by their design (the filament being underdriven, the most famous is the Livermore centennial bulb, which had the filament improperly carbonized). With decent quality control these would be all kicked out at the end of the manufacturing line, because of not meeting the light output performance criteria.

I'm convinced it would be such case, here the bad consequence will be killing the ballasts as mentioned above.
The cause could be either something wrong with the outer so it carries away the heat, or a wrong (higher wattage) burner was assembled into the bulb, or a higher wattage bulb slipped into the line (from the previous batch on the machine,...) and become erroneously marked and packaged as a 35Watter
Logged

No more selfballasted c***

wide-lite 1000
Member
*****
Offline

Gender: Male
View Posts
View Gallery


Re: 50,000 hr + 35 watt hps? « Reply #4 on: November 29, 2018, 05:46:19 PM » Author: wide-lite 1000
Thanks for the replies, 1'st, Blue Halide I agree on the rated life, ge catalog says 16,000 hrs (approx. 4-4 1/2 years) that's why I bought the extras, 2'nd, 100% positive it's the original bulb,  Ryan, I agree that this is some sort of oddball. Medved, I don't know about the arc tube being incorrect, however I asways did notice it lights a little yellower than other wattages of hps, assumed it was normal, I have noticed on start-up it starts lps yellow than goes to white than to hps yellow most other hps i've seen start white than shift to yellow. The arc tube is approx. 2/3's blackened so I decided err on the side of caution and swapped it out with one of the 35 w GE's  the etch is VERY faint but says, "PHILLIPS 35W C35S76/M,OEM. U.S.A., A weird upside-down triangle thing, and then 6M-1 (I assume the date code?) I'm not 100 % positive on the original install date but my initial guess should be close. Lastly, the new lamp does start like "normal" hps, and YES I'M SAVING THE OLD LAMP!!!
Logged

Collector,Hoarder,Pack-rat! Clear mercury Rules!!

BlueHalide
Member
*****
Offline

View Posts
View Gallery

Re: 50,000 hr + 35 watt hps? « Reply #5 on: November 29, 2018, 11:13:04 PM » Author: BlueHalide
Medved brings up a good point, this could very well be a 50w arctube, or a 50w lamp mistakenly stamped as a 35w. Philips and GE 35w and 50w HPS arctubes are physically identical, without the etch you wouldnt know which is which just by looking at them. Given the fact you mention that the 60K hour lamp runs "more yellow" than others really confirms that you may very well have a mislabeled 50w lamp, running it on 35w gear will dramatically extend its life, but at the cost of overheating ballast
Logged
dor123
Member
*****
Online

Gender: Male
View Posts
View Gallery
Other loves are computers, office equipment, A/Cs


WWW
Re: 50,000 hr + 35 watt hps? « Reply #6 on: November 30, 2018, 02:09:57 AM » Author: dor123
Underdriving an HID lamp can also short their life, since the electrodes runs too cold in this case.
Logged

I"m don't speak English well, and rely on online translating to write in this site.
Please forgive me if my choice of my words looks like offensive, while that isn't my intention.

I only working with the international date format (dd.mm.yyyy).

I lives in Israel, which is a 220-240V, 50hz country.

Medved
Member
*****
Offline

Gender: Male
View Posts
View Gallery

Re: 50,000 hr + 35 watt hps? « Reply #7 on: November 30, 2018, 06:15:35 AM » Author: Medved
Underdriving an HID lamp can also short their life, since the electrodes runs too cold in this case.

It depends on how much. 35W instead of 50W is not that much lower, so the electrode may not be the problem. Mainly when HPS are normally rated for dimming down to 40% of the nominal power without life rating reduction, with a 50W tube operated at 35W we are talking about 70%, what is really very slight reduction.

Plus with some HID designs the electrodes are designed to run way above the optimal temperature, just because the thermal balance inside of the arctube does not allow any lower temperature, so with these the lower current will actually mean longer electrode life. However I don't say it is this case, that I do not know.

The cold electrode wear is a limitation mainly for starting cycle lifetime, not that much for mild current reduction.
Logged

No more selfballasted c***

wide-lite 1000
Member
*****
Offline

Gender: Male
View Posts
View Gallery


Re: 50,000 hr + 35 watt hps? « Reply #8 on: November 30, 2018, 07:46:07 PM » Author: wide-lite 1000
Makes a lot of sense, wouldn't be the first time a lamp or anything else was made wrong or mis-labled I tested this theory with 2 ge hps, a 35W + a 50W side by side and other than the etch they do look identical and like Medved said 35 and 50 aren't that far apart so it's possible. As I said earlier the new lamp looks "more hps" than the old one and is a slight bit brighter + it starts "like a normal hps" would and dosen't strobe like the old one sometimes did on start-up. BTW,I did write the install date of this lamp inside the fixture so we'll see how long this one lasts!.... Anybody have any ideas on the date code of the old lamp? (6m-1) THANKS!
« Last Edit: January 04, 2020, 08:19:09 PM by wide-lite 1000 » Logged

Collector,Hoarder,Pack-rat! Clear mercury Rules!!

lights*plus
Member
*****
Offline

Gender: Male
View Posts
View Gallery

George Liv Photo


GoL george.liv.37 UC_OfF2pa6aOcXLAut16jw9g
WWW
Re: 50,000 hr + 35 watt hps? « Reply #9 on: December 12, 2018, 06:03:54 PM » Author: lights*plus
I'm tired of lighting experts & enthusiasts, such as yourselves, second guessing regarding output of HID lamps. BUY a [diffraction] GRATING and find out exactly what is happening to [the spectrum of] an HPS lamp! (Pardon my annoyance)
« Last Edit: December 13, 2018, 02:55:29 PM by lights*plus » Logged
Lightingguy1994
Administrator
Member
*****
Offline

View Posts
View Gallery


Re: 50,000 hr + 35 watt hps? « Reply #10 on: December 12, 2018, 11:38:21 PM » Author: Lightingguy1994
I'm tired of lighting experts & enthusiasts, such as yourselves, second guessing regarding output of HID lamps. BUY a GRATING and find out exactly what is happening to an HPS lamp! (Pardon my annoyance)


What are you talking about ? Whats a grating? and they were just thinking its a 50w tube labeled for 35, it can happen. Its still cool that lamp lasted for so long, I love seeing posts about that no matter the possible cause. Reminds me of that F14T12 durotest tube pic on here somewhere that lasted well over its rated life
Logged

Administrator #5

Medved
Member
*****
Offline

Gender: Male
View Posts
View Gallery

Re: 50,000 hr + 35 watt hps? « Reply #11 on: December 13, 2018, 10:40:59 AM » Author: Medved

What are you talking about ? Whats a grating?

A difractin grating splits the light based on its wavelengths, so you may see the exact spectrum. You may use an ordinary CD and/or DVD as a cheap, readily available grating, the colorless stamped ones are rhe best, because there is no light sensitive layer ( as with the writeable ones) to absorb some components.

The point was to compare the spectrum of the lamp in question vs some known lamp and so match it according to that (e.g. connect a known 50W to that 35W ballast,...).

It may suggest something, but I won't rely on it too much in determining if the arctube is 50 vs 35W, because the discharge atmosphere (so the spectrum) do vary according to make and model even on the same wattage rating. These very low wattage lamps are really on the edge what is feasible, so makers may be helping themselve by deviating from the average composition.
Higher wattages are way nore consistent among makers, but these low wattage may vary a lot.
Logged

No more selfballasted c***

lights*plus
Member
*****
Offline

Gender: Male
View Posts
View Gallery

George Liv Photo


GoL george.liv.37 UC_OfF2pa6aOcXLAut16jw9g
WWW
Re: 50,000 hr + 35 watt hps? « Reply #12 on: December 13, 2018, 03:05:11 PM » Author: lights*plus
I corrected my hasty response. Nevertheless, whether normal, standard, nominal, or abnormal operation, by quickly and easily  employing a diffraction grating (as opposed to fumbling with a dvd or cd) and comparing the hundreds if not thousands of other HPS lamps out there - (35w through 400+ watts) - you can tell exactly how your own lamp system is driven. It's less than $3 with shipping. Do you like cheesecake?

(Too harsh again, I corrected my miserable comments)
« Last Edit: January 17, 2019, 10:36:58 PM by lights*plus » Logged
arcblue
Member
***
Offline

View Posts
View Gallery


Re: 50,000 hr + 35 watt hps? « Reply #13 on: January 17, 2019, 10:01:01 PM » Author: arcblue
I used to think it was simply an exceptionally good HPS lamp that lasted 10 years or more in service. I've had a few and have seen some in service. I have a 35w Sylvania I installed in 2005 in a wall pack on my house that's still going. I only removed it once to replace the fixture's igniter, and put the same lamp back in. I've been doing a life test between it, a Philips and a GE, all on the same circuit. So far it has won.

Medved brings up points I hadn't thought about. This particular lamp DOES burn slightly more yellow than the Philips or GE. It also takes longer to get to full brightness. So I suspect it doesn't have a perfect vacuum (getter flash still looks normal though) and the arc tube is running cooler than it should. It is the same size as the other Sylvania lamps. I had a GE once that lost vacuum (white getter flash) and it never ran up and burned the color of a low pressure sodium lamp.

Also, ballasts in residential grade fixtures like Regent and Lights of America do tend to under drive lamps. Perhaps that's how they manage to get those cheap no-name OEM lamps to make it thru the warranty period. Put one of those lamps in a commercial quality fixture and it lasts only a month. Conversely, I had a Philips 50w last around 12 years dusk to dawn in an LOA wall pack before it cycled...they usually outlast the ballast!

GE Lucalox lamps have an external amalgam reservoir....I haven't seen this on any other modern lamp brand. So GEs  always start out pure xenon-white whereas other brands often seem to have a little sodium emission mixed in with the xenon during ignition, except the very first time they are lit. Not sure why this is but maybe someone else knows. Maybe sodium left on the electrodes? Some lamps go thru a beautiful mercury blue color stage shortly after ignition, most don't until they age quite a bit and some never do it. It seems to have to do with some sodium leaking out during life but I'm not sure. Some will do it when brand new and breaking in and then the Mercury color isn't seen again during warmup.

Also I think factors such as line voltage, ballast tolerances, number of hours per start, etc will make a difference. Sometimes a lamp that cycles as if EOL on one ballast can run for a few more years just fine on another one. I currently have a ProLume 50w that I moved to another fixture for this reason.




Logged

I'm lampin...

lights*plus
Member
*****
Offline

Gender: Male
View Posts
View Gallery

George Liv Photo


GoL george.liv.37 UC_OfF2pa6aOcXLAut16jw9g
WWW
Re: 50,000 hr + 35 watt hps? « Reply #14 on: January 17, 2019, 10:54:42 PM » Author: lights*plus
I'm far from being an expert, but it does look that from ballast to ballast, and perhaps line voltage as well (as arcblue mentions), they play a role in HPS life.

In addition, the ratio of ingredients inside the arc-tube should also be a factor. I have seen (spectrally) Eye Electric 70w HPS lamps with a large Hg content. The mercury emission lines eventually become quite strong in depleted lamps. The lamps look horrible externally -  blackened outer shells in places with dark stained arc-tubes - but keep on going. These look very pink-orange visually.
Logged
Print 
© 2005-2022 Lighting-Gallery.net | SMF 2.0.19 | SMF © 2021, Simple Machines | Terms and Policies