Film-Tech Forum ARCHIVE: Eiki xenon unstable

This is topic Eiki xenon unstable in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

To visit this topic, use this URL:
https://ft-forum.com/ft/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=1;t=012460

Posted by Bruce McNaughton (Member # 2691) on 07-30-2019, 08:40 PM:

I have an Eiki XE300SL The xenon fires up and runs but it fluctuates noticeably. I have run it on a couple of rectifiers with the same fluctuation evident. It appears that the flame is dancing around on the annode surface.
Can anyone advise a solution?

Posted by Frank Cox (Member # 6258) on 07-30-2019, 10:16 PM:

I would say that it's either under-powered or a bad bulb.

Posted by Bruce McNaughton (Member # 2691) on 07-31-2019, 06:14 AM:

No, neither. Correct voltage and current, new bulb. I have this issue with any bulb that I install

Posted by Paul Finn (Member # 10726) on 07-31-2019, 08:25 AM:

Is there an arc stabilizer magnet missing or that has been moved out of position? I assume there have been no wiring changes and the DC polarity to the lamp is correct? It may also be helpful to measure the AC ripple in the lamp DC current under load.

Paul Finn

Posted by Bruce McNaughton (Member # 2691) on 08-01-2019, 12:18 AM:

Thanks Paul
The magnet is in place. Polarity correct. I cannot measure the ripple but the Strong rectifier that I am using gives a perfectly stable result on another projector

Posted by Helmut Maripuu (Member # 2281) on 08-01-2019, 03:33 AM:

How old is the rectifier? maybe time to replace capacitors. The heat from the diodes damages the capacitors.

Posted by Bruce McNaughton (Member # 2691) on 08-01-2019, 09:57 PM:

The rectifier is in perfect condition, running all other xenons with rock steady stability

Posted by Jonathan Wood (Member # 4614) on 08-06-2019, 04:20 AM:

Hi Bruce
Are the bulb connectors ok ? No arcing build up causing poor connection ?
Jon

Posted by Bruce McNaughton (Member # 2691) on 08-24-2019, 07:21 PM:

Yes all connections are solid

Posted by Frank Angel (Member # 248) on 09-02-2019, 09:58 AM:

So if these all check:
*replacing the existing bulb with a new bulb in this projector and and the new bulb exhibits the same problem
*this rectifier works without issue with another bulb in a different lamphouse with no issue
*all connections are tight and show no signs of any kind of physical anomalies in the errant projector
*while you can't test for AC ripple, you say the the rectifier shows no problem in another identical projector/bulb size setup, but is it powered by the same AC source in the known good operating setup? If not, check the ground integrity of the outlet that the rectifier is plugged when it is powering the bulb in the problem projector.

If all the above seems normal, then definitely check the stabilization magnet in the problem projector. Be sure it hasn't lost its flux density or that it has somehow been compromised.

If you have been able to test the bulb and the rectifier together (you have a second projector or on a test rig setup?) and the two are functioning without a wandering arc, then look to the problem projector itself for the problem. What about air flow. Is the bulb being cooled properly in the housing? Check the air flow around the bulb in the test projector (where the bulb is operating correctly) against the same in the errant projector.

Best of luck.