Film-Tech Forum ARCHIVE: Bulb won't light, not the igniter

This is topic Bulb won't light, not the igniter in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Kelsey Crozier (Member # 1489) on 03-08-2004, 01:28 AM:

The equipment is a Strong Super Highlight II with a Strong FXPS-45 power supply and CNA-100 automation.

It started after removing a faulty igniter. The new one made a loud sparking sound different from the normal sound it makes. I then swapped in a known to be good igniter and the same odd sparking noise happened again. Next I made sure the bulb was seated properly and screwed down tight but problem persists.

Could this be a bulb problem? This bulb is at 1700 hours and a little foggy but we routinely get 2000+ hours out of these bulbs.

Or maybe a power supply problem?

Any help tracking this down would be great.

Thanks

Kelsey

Posted by Daryl C. W. O'Shea (Member # 1303) on 03-08-2004, 01:42 AM:

Check for arcing marks on the reflector, etc.

Posted by Michael Schaffer (Member # 1204) on 03-08-2004, 05:27 AM:

Very simple. Your power supply`s open circuit voltage is too low. In the Highlight consoles, the igniter is also powered by one phase of the PS, so if the igniter triggers at all, your open circuit voltage is too low. Simply take a multimeter and measure the DC voltage between the - and + terminals on the power supply. If it is below 80VDC or so, then you have a diode problem. That igniter sound you are hearing is just the igniter vainly trying to ignite on a too low open circuit voltage.
If there is a short circuit to the reflector or lamphouse, you should be able to see that in the viewing window of your console. If the arc goes from the - to the + of the bulb, then you`re in goood shape, as far as the PS is concerned.

Posted by German Marin (Member # 918) on 03-08-2004, 03:08 PM:

Hi Kelsey,
I've chenged igniter a lot of times (on Kneisley lamphouse). When the negative terminal is installed so close to a ground it makes a bridge between the - and the chasis even the same igniter, making a hard noise and doesn't let the bulb to start. Check the negative to be far away from chasis or ground.

Posted by Rick Long (Member # 213) on 03-08-2004, 11:27 PM:

Don't overlook the possibility that this could be arcing from the negative teflon cathode adapter to ground. I have had this happen once or twice. Damned hard to see unless you by-pass the magnetic door interlock. (A small magnet helps here.)

Posted by Richard Hamilton (Member # 321) on 03-09-2004, 08:06 AM:

Just because you routinely get 2000+ hours from that size bulb in that lamphouse, don't rule out that it isn't an issue with the bulb. Try a new bulb and see what happens.

Rick