Sciencemadness Discussion Board

Hg Vapor Lamp Ballasts

MagicJigPipe - 21-6-2011 at 23:26

So, I bought a 100W Hg vapor lamp from a store (Philips A23). I'm going to break the outside glass in order to gain access to UV at < 250 nm to produce ozone. Of course, I will perform experiments related to ozone production via this method. (next I will attempt electric discharge of some sort--probably just with a neon sign transformer that I already have).

Anyway, although I understand the basic principle behind ballasts, I have no (well...some) idea how to build one or where/what kind to buy. The box says to use ANSI H38 type ballasts. Okay, but all of those are extremely expensive ($100+). Also, does the wattage rating matter (as long as it's above 100W, of course)? I have read that using a higher power rating can cause the life of the bulb to decrease. If so, by how much and what is the mechanism for this decrease in life?

Does anyone know of a cheap source for a ballast that would work for this bulb?

Also, is there anything I should know before embarking upon this journey (aside from the obvious like shielding from the UV, protecting from unlikely explosion, etc.)?

Thanks.

Panache - 22-6-2011 at 02:27

i have gotten a 80W, 125W and even up to 250W Hg Vapour lamps to work very effectively simply by ganging the ballasts out of fluoro lights. At the time i honestly didn't know if it would work but it did work fine and apart from the obvious bulkiness of having several solid state ballasts screwed onto a board there's no difference, you don't need a capacitor it only reduces the flickering which is minimal (like 20times a second). So go to the tip theres always thousands of old fluoro fittings and get the ballasts out up to the wattage you need plus or minus like 10%, don't go further over than this.
AAnd you're right generally a modern ballast is pricey.

Magpie - 22-6-2011 at 07:36

Here's a thread that you may find useful:

http://www.sciencemadness.org/talk/viewthread.php?tid=8695#p...

MagicJigPipe - 22-6-2011 at 16:06

Panache, it's been a while since I've encoutered a ballast for a fluorescent lamp. I know of two different kinds:

* The huge and heavy ones that are in a metal casing and are used for the 4-6 lamp fixtures (usually the lamps that are at least a couple of feet long).

* The "solid state" ones that are contained in the bottoms of compact fluorescents.

Of which ones are you speaking?

smuv - 22-6-2011 at 17:37

You can use metal halide lamp ballasts too (they are interchangeable). A good source for cheap lamp ballasts is http://www.e-conolight.com/. Although I haven't checked their prices for years. All you need to do for metal halide/mercury vapor lamps, is buy the bulb (get standard base, not mogal base), the ballast, and a standard porcelin light base (can get that from home depot). Then you wire it up. IIRC two leads go into the transformer primary, these are AC Live/Neutral, then 2 wires com out of transformer secondary, which can be connected to the base. Really simple.

Might want to fact check me though, its been years since I setup any HID lighting.

Edit: E-conolight seems to no longer sell HID lamp ballasts. At any rate, If you look around you can save ~40% compared to buying the actual fixture (which it sounds like you don't need).

[Edited on 6-23-2011 by smuv]

Panache - 25-6-2011 at 17:15

Quote: Originally posted by MagicJigPipe  
Panache, it's been a while since I've encoutered a ballast for a fluorescent lamp. I know of two different kinds:

* The huge and heavy ones that are in a metal casing and are used for the 4-6 lamp fixtures (usually the lamps that are at least a couple of feet long).

* The "solid state" ones that are contained in the bottoms of compact fluorescents.

Of which ones are you speaking?


The first one, maybe I need to look up the definition of solid state as it refers to this sort of stuff, whoops but def the first one I meant.

Intergalactic_Captain - 26-6-2011 at 00:39

Should have posted this in the other thread, but since you need to learn a bit about HID lighting I'll give you the best link I've ever found;

http://www.lumenlab.com/d/index.php

These are the DIY projector people, and there's more information on that forum about every type of lighting imaginable than you'd ever find searching google. If you really want to know the ins and outs of virtually ANY lighting technology (MH in particular there), lumenlabs is the place to start.

...Just to add a bit, "electronic" ballasts are used in HID lighting as well - The general concensus is that they're quieter, lighter, and more efficient - Although they're a hell of a lot more expensive.

...One more, I went into this a bit in the other thread, but DO NOT use a higher-rated ballast system than your bulb is designed for - To put it simply, the reality is counter-intuitive when it comes to any type of arc-type lighting.