21   General / General Discussion / Re: Bulbs with a hole in the base  on: April 15, 2024, 10:09:04 PM 
Started by Caroline - Last post by High Intensity
Ahh, so that might explain why i had a dollarstore C12 lamp attempt to take flight a few months ago.
 22   Lamps / Modern / Re: Any way to look at HID lamps without getting arc eye?  on: April 15, 2024, 06:21:21 PM 
Started by Maxim - Last post by joseph_125
I have a #9 shade welding glass that I use. It's was intended as a replacement glass for a welding helmet, so it wasn't too expensive.
 23   Lamps / Modern / Re: Any way to look at HID lamps without getting arc eye?  on: April 15, 2024, 03:47:27 PM 
Started by Maxim - Last post by marcopete87
I don't have nor do I plan to buy a welding mask

You should, you can buy only welding glass replacement (it's cheaper).
 24   Lamps / Modern / Re: Any way to look at HID lamps without getting arc eye?  on: April 15, 2024, 02:26:55 PM 
Started by Maxim - Last post by Maxim
I actually got eclipse glasses for last week's eclipse. It's certainly bizarre when all you see in your peripheral vision (say, on your shirt) is blinding light, while all you see through the eclipse glasses is one concentrated point. (I tested on a 100WH lamp yesterday.)

Thank you for the suggestions!  ;D 8)
 25   Lamps / Modern / Re: Any way to look at HID lamps without getting arc eye?  on: April 15, 2024, 01:52:34 PM 
Started by Maxim - Last post by RRK
Eclipse glasses are said to pass 0.00032 parts of light, that's 1:3125. About 3x stronger than ND1000. I can look at all my MH arcs with ND1000, but some, like small 150W ones are a bit 'too much'. So 1:3125 might be slightly better.


 
 26   Lamps / Modern / Re: Retrofit sodium lamp questions...  on: April 15, 2024, 06:34:17 AM 
Started by Multisubject - Last post by Medved
Definitely what matters is what the thing is really rated for by the manufacturer, ANY assumption or expectation just by itself could be completely wrong...
 27   Lamps / Modern / Re: Retrofit sodium lamp questions...  on: April 15, 2024, 03:03:02 AM 
Started by Multisubject - Last post by LightBulbFun
The ballast compatibility is published on the lamps datasheet. If the lamp is rated as compatible with a given ballast type, there should not be any issue.

Whether a penning mixture, or any other HPS lamp is compatible with a constant current CWA ballast does not have to always be related to the lamp chemistry itself, but also to the lamp construction, especially its thermal management.

The fact is the constant current ballasts combined with a saturated vapor lamp in its basic form does lead to thermal instability (hither temperature -> higher pressure -> higher voltage drop -> higher power -> higher temperature positive feedback), but manufacturers came with design tricks to eliminate that sufficiently enough so the lamp becomes stable even on a CWA ballast. One example is to put the amalgam reservoir (aka from the vapor pressure perspective the "cold spot" whose temperature dictates the operating pressure) further away from the active arc, so suppressing the thermal feedback, but that is not the only one.
So the question is, whether any such thermal feedback suppression is used in the lamp design and whether it is effective enough to make the lamp really stable so compatible with the constant current drive of a CWA ballast.

From marketing perspective, if a big portion (maybe even a majority) of MV ballasts on the target market are the constant current drive CWA type, I would be very surprised any lamp maker would make a lamp advertised as a "MV replacement" without making sure its design is compatible with the CWA ballast.

Of course very different situation would be when you import the retrofit lamp from a "230V" area where series chokes are 99% of the MV ballasts in use, so where the saturated vapor lamp is stable by itself, so without any such thermal feedback suppression feature. Then you have to really make sure the ballast has the same or similar characteristics as the original series choke (so e.g. the HX transformer or so).




you say that, but the first generation of HPS retrofit lamps sold in the US where indeed incompatible with CWA ballasts, it was one of the big limiting factors when it came to the wide spread adoption


if you look up the GE E-Z-Lux and Sylvania Unalux, you will see how their entries in the catalogs and such like are plastered with warnings about being suitable for operation only on HX-Autotransformer or Choke type ballasts


the other main problem is besides general instabilities as your describe is that at the end of life the voltage of a HPS lamp rises and on a constant current ballast like a CWA ballast, this can lead to dangerously high power levels


it was not until unsaturated HPS lamps where devloped did CWA compatible HPS retrofit lamps become possible






dedicated CWA HPS ballasts I understand work around the issue by having a very low OCV, so the lamp arc voltage cannot rise that much before it exceeds what the OCV can support and the end of life lamp will thus safely cycle
 28   Lamps / Modern / Re: Retrofit sodium lamp questions...  on: April 15, 2024, 02:22:28 AM 
Started by Multisubject - Last post by Medved
The ballast compatibility is published on the lamps datasheet. If the lamp is rated as compatible with a given ballast type, there should not be any issue.

Whether a penning mixture, or any other HPS lamp is compatible with a constant current CWA ballast does not have to always be related to the lamp chemistry itself, but also to the lamp construction, especially its thermal management.

The fact is the constant current ballasts combined with a saturated vapor lamp in its basic form does lead to thermal instability (hither temperature -> higher pressure -> higher voltage drop -> higher power -> higher temperature positive feedback), but manufacturers came with design tricks to eliminate that sufficiently enough so the lamp becomes stable even on a CWA ballast. One example is to put the amalgam reservoir (aka from the vapor pressure perspective the "cold spot" whose temperature dictates the operating pressure) further away from the active arc, so suppressing the thermal feedback, but that is not the only one.
So the question is, whether any such thermal feedback suppression is used in the lamp design and whether it is effective enough to make the lamp really stable so compatible with the constant current drive of a CWA ballast.

From marketing perspective, if a big portion (maybe even a majority) of MV ballasts on the target market are the constant current drive CWA type, I would be very surprised any lamp maker would make a lamp advertised as a "MV replacement" without making sure its design is compatible with the CWA ballast.

Of course very different situation would be when you import the retrofit lamp from a "230V" area where series chokes are 99% of the MV ballasts in use, so where the saturated vapor lamp is stable by itself, so without any such thermal feedback suppression feature. Then you have to really make sure the ballast has the same or similar characteristics as the original series choke (so e.g. the HX transformer or so).
 29   General / Off-Topic / Re: What did you do today NOT lighting wise  on: April 15, 2024, 01:45:39 AM 
Started by Bulbman256 - Last post by RyanF40T12
I had 2 jeeps that had the 5 speed trannies.  An 89 Cherokee, and an 89 Wrangler.  They were fun but that was when I was younger. Now a days I appreciate the auto trannies.  Now.. If I had a sports car I might enjoy a manual but we'll see. 
 30   General / General Discussion / Re: What did you do today lighting wise?  on: April 15, 2024, 01:43:44 AM 
Started by RyanF40T12 - Last post by RyanF40T12
Removed emergency lighting and equipment from my 2018 Chevy 2500HD Silverado Duramax.  Potentially getting ready to sell the truck and get another. I had an emergency lighting upfitter that installs equipment for all the law enforcement agencies around here install the stuff back in late 2019 when I got the truck.  Have had a few offers for the truck lately that are too good to ignore.  Lots more folks looking for used trucks now given how high the prices are on new vehicles.   
Pages: < Previous Next > 1 2 [3] 4 5 ... 10
© 2005-2024 Lighting-Gallery.net | SMF 2.0.19 | SMF © 2021, Simple Machines | Terms and Policies