Phoebus Ultra Arc IIs

[shiben]

One of the facilities I routinely work in just dug out some old Phoebus Ultra Arc IIs that have been festering in the basement. I was cleaning them up and trying to get them working today, and discovered that the fuse was missing. Does anyone know where I can buy the fuse that works in the unit? Second, is it even worth it to get them running? Specs online say that they are decently bright, at least more so than our Lycian StarkLite IIs, at a throw of 179'. However, some old hands at the college says that they are actually very dim. Any commentary on this? Any help would be appreciated.

[NickJones]

They could be using the wrong lamps in them to make them look dim, who knows, yes, it's good to have as many fixtures in your inventory as possible, and for the small amount fuses cost, it is really worth your while just to have them there on hand if you need them. I can't tell you what fuses they use, take some photos and tell us the writing on the ends of the fuse.
Nick

[derekleffew]

Originally Posted by shiben

... and discovered that the fuse was missing. ...

Originally Posted by NickJones

... I can't tell you what fuses they use, take some photos and tell us the writing on the ends of the fuse.
Nick

Taking photos of, and reading writing on, non-existent fuses is a skill few if any of us have mastered, NJ.


From the Ultra Arc II manual.pdf:

If blower fails to run, check power and fuse. Replace fuse with 7 amp 3AB fuses.

The fuse should be available from any electronics supplier. Here's one source, 61¢/each: Fuse 3AB 0.25 X 1.25 Fast BLO 8 AMP Ceramic Sold Individ | Littelfuse | 314008P.

According to the manufacturer's website, this is still a current model, and fuses or assistance will most certainly be available from them.

As to the speculation that they will be brighter than your StarkLite IIs, extremely doubtful. There was much truth in the nickname "Ultra Dark" (although the 400W HTI was a huge improvement over the Marc-350).

[shiben]

Great, thanks guys!

[JD]

Had a pair of the original Ultra Arcs that used the Marc 350. They weren't bad as long as the bulb was brand new. The Marc's had a globe the size of a pea, so the brightness honeymoon was soon over! It would pit and frost and the output would drop like a rock. The life on the Marc's back then was 50 hours: 15 great, 15 ok, and 20 that was like a death vigil. I would certainly think the HTI 400 was a giant improvement. Everything about the design depended on a point source in an exact location, so I would suspect proper alignment is a critical factor. If anyone played with the optical set up, that may be your big problem. The ballasts on the 350 unit were failure prone, but I would hope they got that under control on the II's.

[NevilleLighting]

There's a reason these were nicknamed "Ultra Darks". However, I do have to admit that I ran across these on a recent gig and they did fine with a 125' throw. If you are on a tight budget and you have lots of time to fine tune these, you may do ok. Pull out the working fuse and go buy a half dozen like it.