Firing Ushio Using Tar Ballast

PeterW · #1 03-24-2005, 07:13 PM

I recently bought a tar ballast with pulse start and am using Ushio 175watt bulbs. The problem is they don't fire up properly.

Even when the bulbs are screwed in very tightly in the mogul. It would remain unlit even having the ballast on for hours.

It needs a little jiggle and then would fire up. This means I can't put the MH on a timer.

Right now the bulb sits on top on a glass top. Any ideas? Is this the right ballast/bulb combination?

Thanks in advance!

Peter

Delphinus · #2 03-24-2005, 07:42 PM

It should be the right combo, Ushio's are pulse-start.

You're sure it's a pulse start ballast? It sounds like you're using a probe start and not a pulse start. There should be three components, the transformer, the capacitor and an ignitor (looks like another capacitor, but is different). If only two then it's a probe start (or you're missing a component

).

I use probe starts to fire my Ushios (that's just what I have, and have never bothered buying new ballasts). I find they are fussy to start for a few weeks at first (but they do eventually fire on their own, it might just take 5-20 minutes). Swapping the leads sometimes helps. Also check all your connections and make sure they're really really solid. Eventually the bulbs sort of burn in and fire up OK.

Going for hours though, without starting, then something's not right.

Can you get into the socket and bend the centre contact out a bit (so that it presses harder into the lamp threads)?

What about the nipple orientation? I hear varied opinions on whether this matters or not, but maybe make sure that it's pointing upwards. Reorientate the socket if you need to.

HTH ..

PeterW · #3 03-24-2005, 07:57 PM

Tony,

Thanks for your reply. I'll go home and check to see whether it is probe or pulse start. Now I know how to check

I bought the ballast and bulbs used. The bulb is about 6 months old. Everything should be burned in.

Good idea about popping out the center of the socket. Will try it. More surface area to make contact.

Will let you know how I make out.

Peter

KrazyKuch · #4 03-24-2005, 08:49 PM

Personnaly to me it sounds like a Loose Splice...You might want to check them all and make sure they are all good!!!

Zerandise · #5 03-24-2005, 08:59 PM

The ballast and bulbs ran great for 6 months. Maybe a loose connection after you rejoined all the wires? Im sure ballast are probe start. I used them for over a year with 2 types of bulbs.

sorry you are still having troubles

Delphinus · #6 03-24-2005, 09:02 PM

It's not too uncommon to see this sort of thing. But if they ran OK then they can run OK once more

It's probably a loose connection (or splice or whatever the term is) somewhere then. Check every connection. Also like I said before, I don't know why this would make a difference, but I've found that sometimes things just work better after switching the leads to the socket.

PeterW · #7 03-24-2005, 10:34 PM

Tony,

Just wanted to confirm that the nipple is the round metal piece that sits on a square piece.

Currently, it is facing down.

Will try to reorient it.

Peter

Aquattro · #8 03-24-2005, 10:40 PM

Quote:

Originally Posted by Delphinus

What about the nipple orientation? I hear varied opinions on whether this matters or not, but maybe make sure that it's pointing upwards. Reorientate the socket if you need to.

It's never made a difference to my bulbs, and there is an article that dispells this myth. Searching RC will find it.

Delphinus · #9 03-24-2005, 10:49 PM

I've read all that and I'm certainly not going to formally dispute any of it. I'm just saying ... sometimes it made a difference for me. Not in running any "better" or "brighter" or anything like that, but changing the orientation made the lamps fire in cases where they weren't before. Don't ask me why or how. But I thought it's just one more thing to fiddle with. It can't hurt (can it?

I suppose don't apply so much force to the lamp that you torque the glass casing apart or something).

Anyhow, I realize it's a long shot, but I thought it couldn't hurt to look at it.

Quote:

Originally Posted by PeterW

Just wanted to confirm that the nipple is the round metal piece that sits on a square piece.

Currently, it is facing down.

Ummm ... no I don't think that quite sounds like it. If you look at the glass arc tube, there should be a little bump on one side of it, near the centre. It's some artifact of the manufacturing process. Maybe it's where whatever elements are injected into the arc tube and then it's sealed or something like that. Anyhow, it looks a little like a wart on the glass arc tube.