81   General / Off-Topic / Re: Do you collect other things besides lighting??  on: October 18, 2020, 09:44:41 PM 
Started by mefurd98 - Last post by Bulbman256
We seem to collect all sorts of stuff, if there's an empty flat surface, it doesn't stay empty for long  ::)

Oh and there always seems to be quite a lot of dust  :lol:

Well if its flat, just make it into a slope so your precious lamps and other valuables slide right off making it collector foolproof! :lol: :lol:
 82   Lanterns/Fixtures / Modern / Re: Is there such a thing as a preheat 2x4 fluorescent troffer for drop ceilings?  on: October 18, 2020, 09:41:05 PM 
Started by WorldwideHIDCollectorUSA - Last post by joseph_125
Early troffers like these Daybrite units from 1941 were preheat. The 1x4 size was more common back then, probably because 1x1 tile ceilings were more common back then compared to 2x4 T bar ceilings. The troffers in that catalogue were all preheat and a 2x4 model was also made.

Early troffers were typically a lot deeper compared to modern troffers and had the ballast above the lamps. I've seen a 1x4 one before, it was from the 1950s and had a huge 25/60Hz ballast. The ballast was the size of a modern VHO one.   

Converting a rapid start T12 troffer to use preheat is fairly straightforward. You'll need 2 modern (post 1950s) tulamp preheat ballasts which have the exact same mounting as a 2xF40 ballast. You'll need to get starter sockets and drill 4 holes in the ballast cover for the starters though.

BTW, preheat F40 ballasts were made in a 3 lamp lag-lead-lag configuration and 4 lamp series F40 rapid start ballasts were made at one point too. Those never really took off and most troffers continued to be fitted with 2 2 lamp ballasts until they stopped making new magnetic F40T12 troffers in around 2005 or so.
 83   General / General Discussion / Help with Identification of 1990 Street Light  on: October 18, 2020, 09:40:57 PM 
Started by AJCSI - Last post by AJCSI
Hello,

I am a forensic crime scene analyst. I'm working on an old case and I would like to know the make and model of the luminaire in my photo so I can get a spec sheet to learn about the light pattern distribution.

Here is what I know: The light was being used in 1990 in San Francisco. The city data shows that it was a 100w high pressure sodium.

Here is a link to the photo (I tried to attach it here for 30 minutes -- seems not possible; even at a size of 118kb.)

https://www.dropbox.com/s/l9mve183wthglpv/Luminaire%201990%20A.jpg?dl=0

Thank you if you can help.

AJ
 84   Lanterns/Fixtures / Modern / Re: Is there such a thing as a preheat 2x4 fluorescent troffer for drop ceilings?  on: October 18, 2020, 09:20:46 PM 
Started by WorldwideHIDCollectorUSA - Last post by WorldwideHIDCollectorUSA
American preheat ballasts for F40T12 are usually available for 2 lamp max. For more lamps, I know only rapid-start ballasts.

Actually, many US 4 lamp troffers used 2 ballasts that operate 2 F40T12 lamps in series.
 85   Lanterns/Fixtures / Modern / Re: Is there such a thing as a preheat 2x4 fluorescent troffer for drop ceilings?  on: October 18, 2020, 09:14:18 PM 
Started by WorldwideHIDCollectorUSA - Last post by dor123
American preheat ballasts for F40T12 are usually available for 2 lamp max. For more lamps, I know only rapid-start ballasts.
 86   Lanterns/Fixtures / Videos / Re: LED Street Lights Blinking  on: October 18, 2020, 09:11:24 PM 
Started by CreeRSW207 - Last post by dor123
There’s a LED fixture that flickers but doesn’t fully shut off, does that have to do with power supply.
The problem can also because of the LEDs themselves. The driver may not be able to start a dead LED so it will try to start it, resulting in flashing. See here: https://www.youtube.com/watch?v=mk9h2IuMvfk
 87   General / Questions & Suggestions / Re: Update the Instagram icon  on: October 18, 2020, 09:07:49 PM 
Started by Lumex120 - Last post by Lumex120
Update: It's been changed! I don't know if an admin did it or if it's from the SMF upgrade, but if it was an admin, thanks! It was really bothering me lol
 88   General / General Videos / Informative video on SOX lighting  on: October 18, 2020, 09:06:19 PM 
Started by WorldwideHIDCollectorUSA - Last post by WorldwideHIDCollectorUSA
Has anyone learned any valuable information from watching this video on SOX street lighting:

https://youtu.be/sfCGyiLOKu4
 89   Lanterns/Fixtures / Videos / Re: LED Street Lights Blinking  on: October 18, 2020, 08:41:18 PM 
Started by CreeRSW207 - Last post by WorldwideHIDCollectorUSA
Phasing out HID lighting in favor of LEDs will force drivers to cope with flashing street lights and that will increase the number of automotive accidents.
 90   General / Off-Topic / Re: Headlights on Vacuum Cleaners  on: October 18, 2020, 08:34:02 PM 
Started by WigWag - Last post by WigWag
Well , what if you want to vacuum in the dark ?  :lol:

Har-dee-har-har! That's what they put headlights on lawnmowers for  :lol:

@sol I much prefer carpet but I've always wanted hardwood
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