High Pressure Mercury Lamps

[Sigurthr]

Will these lamps light up under a plasma globe like fluorescent ones do.?

They'll light up from RF energy, sure, but since the pressure is so high in the outer jacket it takes a strong field and there isn't a lot of activity. The arc tube lights easy because of the low pressure of cold mercury, but it's a tiny glow.

 

[joeyss]

They'll light up from RF energy, sure, but since the pressure is so high in the outer jacket it takes a strong field and there isn't a lot of activity. The arc tube lights easy because of the low pressure of cold mercury, but it's a tiny glow.

I over clock a 12 volot plasmas globe to 20 ( cool it with a fan under it.) will it light LPS lamps?

 

[The Lightning Stalker]

Will these lamps light up under a plasma globe like fluorescent ones do.?

Yes they do, but not as brightly.
They can also exhibit some plasma globe like
effects.

 

[Sigurthr]

I over clock a 12 volot plasmas globe to 20 ( cool it with a fan under it.) will it light LPS lamps?

I would not overvolt the supply, it isn't like a PC's CPU - the issue isn't purely thermal. There are components inside which are probably only rated for 16V (normal for a 12V device made inexpensively) and applying 20v will blow them up.

If you disassemble the plasma globe and attach the driver's HV lead to one terminal of the LPS lamp, and connect the other LPS lamp terminal to ground or 12V negative it should work. If you do this with a HPS or HPHg you'll only get the tiny arc tube to glow, but in a LPS the arc tube is much larger and glows much brighter from the Neon fill gas.

 

[joeyss]

I would not overvolt the supply, it isn't like a PC's CPU - the issue isn't purely thermal. There are components inside which are probably only rated for 16V (normal for a 12V device made inexpensively) and applying 20v will blow them up.

If you disassemble the plasma globe and attach the driver's HV lead to one terminal of the LPS lamp, and connect the other LPS lamp terminal to ground or 12V negative it should work. If you do this with a HPS or HPHg you'll only get the tiny arc tube to glow, but in a LPS the arc tube is much larger and glows much brighter from the Neon fill gas.

I have a massive fan under it and i hook it up to my psu with a cigarette lighter adapter and jack. I limit the current so it cant run away to infinity. It stayed cool all the times i tested it.


What's the cheapest I could get a LPS lamp w/ a ballast btw? I like 589nm

 

[Sigurthr]

What's the cheapest I could get a LPS lamp w/ a ballast btw? I like 589nm

Find a friend in the local road/power crew who services street lamps and ask if they have any you can haul away for free. Barring that, eBay. Genuine ballasts are expensive, but you can use certain fluoro ballasts just fine. Btw, there is a separate thread for LPS, so head there, this one is for HPHg.

 

[DashApple]

picked up a Old G.E.C 250W self ballast mercury lamp , according to someone at lighting gallery it was made in 1977 : D , So its old but still works : D

P1000207 by TwirlyWhirly555, on Flickr

P1000209 by TwirlyWhirly555, on Flickr

 

[Sigurthr]

How's the color temp from it? I'd assume pretty warm being self ballasted and phosphored.

 

[ped]

Get that thing emitting photons!

Lead free solder...one of the worst inventions....ever.

 

[paul1598419]

IDK, Ped. after all the leaded solder I inhaled over the years I wish there was a better way than blowing the fumes away while soldering. Sorry for being off topic.

 

[trencheel303]

That self ballasted GEC is a beaut.

Now here's something that I've been hankering after from almost the moment I started collecting... a medium pressure mercury lamp. And I was lucky enough to get two, although one doesn't work but is a very old early example:

The one in the bell jar is the duffer, a very old Mazda that has done a number hours by the looks of it, and has a dead arc tube. It unfortunately wouldn't go, but I decided to keep it as a display unit and because of its historical significance. The lit picture is a newer GEC-OSRAM type, the dead giveaway being the type of arc tube support it has. I ran this for about 10 minutes just to see it warm up and get photos/video, it is the same as a high pressure lamp except the arc tube is just a lot bigger, and the pressure is around 5 atmospheres rather than 10.

These can apparently become hard to start in their old age and even the "working" one, which looks NOS, took a few goes and when I was about to give up it fired.