Film-Tech Forum ARCHIVE: Another IREM X75DM question

This is topic Another IREM X75DM question in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Dominic Espinosa (Member # 2122) on 02-07-2012, 08:42 PM:

Hey gang,

gimping along till March when we go full tilt boogie with the digi's...

I have a rectifier in another screen from last time that seems to have an ignition problem.

If I switch the lamp on the ignitor fires and I get big flashes of light form the lamp as if it's striking and then dieing.
It doesn't look like the usual arc jumping with no strike.

I have noticed that if I switch the console to manual, power on the rectifier and then tap the manual ignition button quickly it will strike right up in 1 or 2 tries.

There's no unusual noise or anything of that nature it seems to me like it's just having a hard time switching off the auto-strike in time? But lowering the threshold on the auto-strike seems to yield no attempt to strike at all.

No-load voltage is 90, operating current is ~80amps.

This is a 2k lamp. It's getting on in hours but still relatively new but I'm leaning toward it being the culprit out of gut instinct.

However, once lit the arc is stable, very little flicker on-screen, and I'm seeing 18fl at the center and 12 at the edges (Cinemechanica lamphouse)

Just looking for a second opinion before I go any further. Thanks guys!

Posted by Monte L Fullmer (Member # 2797) on 02-07-2012, 08:49 PM:

Osram? Do a bulb change and see what happens.. Osrams are known to crap out with no visual issues.

Or, autostrike section of the rectifier (esp the relay) is getting tired, esp if you can fire the bulb right away in manual mode.

Posted by Louis Bornwasser (Member # 3063) on 02-08-2012, 06:27 AM:

On that rectifier, you should expect a minimum of 5-7000 hours on an Osram. Best combination out there.

I would go toward the RA relay. The little circuit board just plugs in. Borrow from another rectifier if you have one. Louis

Posted by Dominic Espinosa (Member # 2122) on 02-11-2012, 03:15 PM:

Looks like it was the relay board.

Can I just swap the relay on it?
We haven't got any spares...