old mercury bulb fixtures

We have several old style mercury vapor fixtures like this installed under a soffit (this one hanging out so I could take a picture of it): http://i207.photobucket.com/albums/b...1/IMG_1427.jpg

Two questions:
1. I tried replacing a burned-out bulb inside one of these fixtures, the burned-out one being a Philips 100W H38HT, with a new Philips 100W C100S54/ALTO that has also has the symbol Hg printed on the bulb with a circle around it. I am unsure whether the replacement bulb is the proper replacement, but I suppose it isn't because it won't work in the fixture. If the replacement bulb has the Hg symbol doesn't that mean it's a mercury vapor bulb that should work? (Apparently the replacement bulb is a high pressure sodium type, but if so why does it have that Hg symbol on it, I don't get it?)

2. I was reading the following in WikiPedia about mercury bulbs: "In the USA, ballasts and fixtures were banned in 2008. Because of this, several manufacturers have begun selling Compact Fluorescent replacement bulbs for mercury vapor fixtures, which do not require modifications to the existing fixture." I'd be interested in finding/obtaining such compact fluorescent bulbs that could possibly work in these old fixtures. Would these type of replacements simply work in these fixtures, even if the ballasts/transformers were shot. Is it really true I could just use the CF bulbs with no modifications to the existing fixture.

Any answers/comments appreciated.

 

1- Your new lamp has the HG symbol because it does contain mercury, but it is NOT a mercury vapor lamp, it is a high pressure sodium lamp, which casts an orange glow like streetlights in most areas. Different types of HID lamps are not generally interchangeable. Your two options with those fixtures are:
A- Get and install a 100w mercury vapor lamp. Most home centers still stock them in my area.
B- If the sockets are medium base (like a standard incandescent lamp), you could disconnect the ballast and install CFL's, but expect less light output.

2- I have not seen any direct CFL replacements for mercury lamps. I can't answer this one, sorry. I can tell you that if you know that the ballast is shot, either use option B (above), or consider replacing the fixtures. If you do, you might want to consider metal halide fixtures. They have a high color rendering index, and are efficient. These are the type of lamp usually used on car lots & on ball fields.
Good luck!
Andy

 

Thanks Andy,
The sockets are mogul base, so in that case could there be an option of installing a mogul-socket to standard-socket adapter, if such exists? I wouldn't mind less light output with a CFL lamps, if all I needed to do was disconnect the ballast and install them. Otherwise if my only other option is to consider replacing the fixtures with metal halide ones, I'm not sure if I like the idea of that type of light as you mentioned (used on car lots and ball fields).

Also, what about these "self-ballasted" MV lamps as shown here: Self-Ballasted Mercury Vapor Lamp

I was thinking thjese self-ballasted type might make for an easy change-out, although I notice the mogul-base aren't offered in 100W.

 

Mogul to medium adapter. Leviton 000-8681 Mogul To Medium Adapter, 660W

 

Great, thank you ray.

On my existing MV fixtures, there is at each one an old 120V transformer along with a capacitor. I notice the specs for the adapter say "250 voltage". What does that 250 voltage refer to? The adapter should work fine in a regular 120 volt circuit shouldn't it?

 

The 250V refers to the maximum voltage the adapter can handle it will work fine on a 120V circuit

 

I see. Thanks. From this supplier, as shown in this link, there are two slightly different of these adapters available, one of which describes it as a "4KV adapter". Not sure which I should get. Comment please?
Search leviton 8681 - Grainger Industrial Supply

 

The 4KV is only needed if you are using it with a an HID (High Intensity Discharge) Fixture with a Pulse start or ignitor (Metal Halide or High Pressure Sodium) If you are going to bypass the ballast a regular or the cheaper adapter will work

 

Okay thanks again. When I get the adapter I'll see how it works out with a CFL and with the dead ballast bypassed. What might be an equivalent CFL size to use as a replacement for the the 100W mercury vapor lamp?

 

This will be a little tricky, because CFL's are rated in incandescent equivalents. Go by lumens, which are a measure of light output. A new 100w phosphor coated mercury vapor lamp is rated at 4000 lumens, but they will dim slightly with use, making their average lumen output at 2800. In order to come close to the light output of that mercury lamp, you will need a CFL of approximately 55w, like this one:

Lamp, 55TWIST/27 - Compact Fluorescent Lamps - Lamps - Lighting : Grainger Industrial Supply

This will still be slightly dimmer than the mercury lamp, but since you said you wouldn't mind a dimmer lamp, these might be just the thing. Also, since you are in a colder climate, CFL's will dim a bit as the temperature drops ...just something to be aware of.
Andy

 

Cool. Thanks very much for the info and explanation. Will post back on how it all works out.

 

Okay. I obtained the adapter socket and installed it, along with a small CFL bulb for testing. Here's a picture of it, wired directly with the ballast/capacitor removed/bypassed. It didn't light. Why not? This is a good but used bulb I took from another regular fixture just to test for now. But no light here... why??

 

All connections tight? Do you have 120V at the socket? Be sure you are using a meter, not a non-contact tester. That will not detect an open neutral. It is also possible, but not likely that the base of the CFL is slightly shorter & not making contact with the center button at the bottom of the socket. You might want to try a plain old incandescent bulb for testing purposes too.
Let us know how that works out!

 

Photocell? I'd put power directly to the socket temporarily just to rule out any other problem.

 

I did noted that you have greenfeild flex conduit so take a NCV and test it to make sure you have power there otherwise somewhere along the run at the other luminaire or junction box location you may have open splices so check it out as well.

After you get the photocell bypassed by either tape up the lens or run a jumper between black et red at photo cell only for testing purpose { unless you have timer in there as well }

Merci,
Marc

 

Okay! Got 'r going. The problem was that the center tang in the mogul socket needed to be bent up slightly so it'd make contact with the center button of the adapter socket. At least it was something simple. Thanks.

 

It'd be nice if when screwing in the smaller size adapter into the mogul size socket that it would screw in easily, as well as unscrew back out easily. I'm finding that the friction of the metal socket threads screwing together is such that it is quite difficult getting the adapter to screw in all the way, and that once I might manage to screw it in all the way that it is nearly impossible to unscrew again. Could there be a particular lubricant/grease that I might apply to the threads which would help? Something that would be safe, of course, for this application, and that would work.

 

Petroleum jelly such as Vaseline is what I have always read to use.

 

You probably have both aluminum base and aluminum shell and aluminum on aluminum tends to bind. I have had good results with WD-40. Just apply a small amount to the threads and wipe dry with a clean cloth and the threads will no longer bind.

 

In the one fixture I've modified with the mogul to medium adapter and with one of these these particular (brand new) bulbs installed Lamp, 55TWIST/27 - Compact Fluorescent Lamps - Lamps - Lighting : Grainger Industrial Supply after a few days I noticed the light was out already. I took the non-working bulb out and tried in it another known working fixture, where it still did not light, indicating it was already burned out. So I went ahead and put another new one of those bulbs in the modified fixture again, where it lit up fine as before. I'm concerned now that the modified fixture is somehow cause for the new bulb to burn out like that in short period of time. Or perhaps the new bulb burned out quickly because it was somehow defective? Comments please.

 

Bought a new package of 60 watt generic incandescent bulbs. Every one in the package burnt out in less then a minute in the same fixture. New package of bulbs from a different manufacturer no problem. A CFL is a lot more complex then incandescent with its electronic ballast so I would easily believe bad bulb.

On the plumbing front over the years I have bought several brand new supply lines that dripped at the connection no matter what you did. Switched out with supply lines from a different store no leaks.

Yes factory can be bad. Worst was a bathroom plumbed from scratch with Chinese made galvanized fittings from BigBox. Every fitting dripped despite all efforts. Had to replace every one with American made parts from a plumbing supply. With the new fittings no drips first try.

 

Okay thanks Ray for your input. So I called the retail place I purchased them from, and explained how I strongly suspect a bad bulb. They said they'd send a replacement free of charge.

 

But if it is from the same lot you may have the same problem.

 

If I have the same problem with the replacement, or with any one of the five other identical bulbs that came packaged out of the same 6-pack box of bulbs, then I'll contact the retailer again and ask them to replace these with a new 6-pack from a different lot. But I'd expect there will be some reason they'll say they can't do that.

 

Since replacing the (new) burned out bulb I was mentioning in my previous post with another new one yesterday, I've had this new replacement burn out too, within 24 hours. Another identically modified fixture adjacent to this problem fixture also has a new bulb I installed from the same factory six-pack of bulbs, and it so far after four days has remained lit just fine. So now I'm leaning toward ruling out a bad batch of bulbs, and instead suspect a circuit/wiring problem is causing these bulbs to burn out after a short while in this particular fixture. What's likely going with the cirtcuit to cause these CFL's to burn out like this? What can I check first to troubleshoot? Any suggestions/advice appreciated.

 

What is the voltage of the old ballast? Is it 120V? If 240 or 277VAC there is your problem what type of circuit switches these fixtures? Photocell wall switch etc? Most cheap CFLS can't be used with a Photocell or other electronic switch and are only rated for 120VAC operation

 

120V old ballast. I double-checked my wiring connections the other day; it looked like some of the strands in the stranded wires were broken at one of the connections, so since I repaired that connection then the bulb has been working fine (it's been four or five days now with no more problem). A photocell wall switch is what tells the light to go on when it gets dark. I know the cheap CFL is not supposed to be used with a photocell, but for some reason its been working ok.

 

Since it originally had a ballast it probably has a three wire photocell. The problem comes when the photocell has no neutral and constantly draws a trickle of current through a fixture. If you have a neutral it doesn't have too.

It previously had a ballast for the mercury vapor lamp and worked so it should work with the CFL ballast.

 

Well thats good news. I more expected somebody would probably tell me the CFL will surely fail soon with the photocell in the circuit. thanks ray