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Topic: Ignitor Problem

Martin McCaffery
Film God

Posts: 2481
From: Montgomery, AL
Registered: Jun 99

posted 08-11-2007 08:11 PM

Strong 60XD, Christie XM rectifier.

Lamp won't ingnite. No arc. Getting a slightly audible hiss from inside the lamphouse when using the emergency ingnitor button. Bulb has only 500hrs and no visible signs of problems. Have not tried switching it out yet.

All safety switches and internal fans running and indicator lights lit.

Have I just lost my ignitor?

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Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 08-11-2007 08:28 PM

If the lamp looks normal probably yes. In an energency use a cattle prod to ignite the lamp.

Mark

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Michael Schaffer
"Where is the
Boardwalk Hotel?"

Posts: 4143
From: Boston, MA
Registered: Apr 2002

posted 08-12-2007 01:04 AM

Are you kidding, Mark?

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Leo Enticknap
Film God

Posts: 7474
From: Loma Linda, CA
Registered: Jul 2000

posted 08-12-2007 03:14 AM

And even if you're not, how many projection booths just happen to have the odd electric cattle prod lying around in the tool cupboard?!

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Stephen Furley
Film God

Posts: 3059
From: Coulsdon, Croydon, England
Registered: May 2002

posted 08-12-2007 04:45 AM

quote: Martin McCaffery
Getting a slightly audible hiss from inside the lamphouse when using the emergency ingnitor button.

That sounds like the ignitor is working; are you sure that the main d.c. supply is getting to the lamp ok?

I had a lamp that wouldn't strike a few months ago, if I pressed the ingition button I could hear it, as you describe, and through a small hole in the bottom of the lamphouse I could actually see a dim spot of light on the floor from the ignition sparks. Are there any holes in your lamphouse where you could see this?

In my case it turned out to be no three phase supply to the rectifier, breaker tripped in the main distribution panel. Irem rectifier, had no indication of incoming supply being healthy.

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Dustin Mitchell
Phenomenal Film Handler

Posts: 1865
From: Mondovi, WI, USA
Registered: Mar 2000

posted 08-12-2007 06:32 AM

quote:
And even if you're not, how many projection booths just happen to have the odd electric cattle prod lying around in the tool cupboard?!

Some chains have resorted to rather unorthodox crowd control techniques....

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Martin McCaffery
Film God

Posts: 2481
From: Montgomery, AL
Registered: Jun 99

posted 08-12-2007 11:51 AM

quote: Stephen Furley
That sounds like the ignitor is working; are you sure that the main d.c. supply is getting to the lamp ok?

Power in coming in fine. No little light as far as I can tell. Also not getting the thump we usually get on ignition.

As for the cattle prod, wouldn't a taser be more convenient? [Wink]

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Stephen Furley
Film God

Posts: 3059
From: Coulsdon, Croydon, England
Registered: May 2002

posted 08-12-2007 12:25 PM

quote: Martin McCaffery
Power in coming in fine. No little light as far as I can tell. Also not getting the thump we usually get on ignition.

Do you mean that a.c. power is coming in to the rectifier, or d.c. power is coming in to the lamphouse? The 'thump' sounds like a contactor; if that isn't working for some reason then you wouldn't be getting any power to the lamp. I don't think it's an ignitor problem; it sounds more like either a faulty cotactor, or whatever is operating it, switch, relay etc.

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John Hawkinson
Film God

Posts: 2273
From: Cambridge, MA, USA
Registered: Feb 2002

posted 08-12-2007 02:53 PM

Cattle prod: 9kV
Xenon lamp ignition: 20-50kV
Taser: 200-300kV

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Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 08-12-2007 07:44 PM

Push down voltage switch (or, put a VOM meter across the lamp leads coming out of the rectifier with the VOM on DC settings) then turn rectifier on and before pressing ignition. If voltage doesn't swing up past 130VDC before ignition, then, recifier has gone kaput, or the contactor for the incoming 3ph current isn't making the clean connections when closing - the ignitor is fine.

This is the most common results of ignition failure and most blame the ignitor for failure in bulb ignition.

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John Hawkinson
Film God

Posts: 2273
From: Cambridge, MA, USA
Registered: Feb 2002

posted 08-12-2007 08:22 PM

WARNING:

DO NOT attempt to strike the bulb (manually or autostrike) with a VOM connected. You will destroy your meter with the high-voltage pulse.

--jhawk

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Monte L Fullmer
Film God

Posts: 8367
From: Nampa, Idaho, USA
Registered: Nov 2004

posted 08-13-2007 03:41 AM

(ain't that the truth - found that one out the hard way the one and only time..luckilly it just knocked out the fuse inside)

Forgot to say, if using a VOM, run the test leads before the ignitor - preferably at the output of the diode bank where the heavy bulb leads are attached.

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Kenneth Wuepper
Phenomenal Film Handler

Posts: 1026
From: Saginaw, MI, USA
Registered: Feb 2002

posted 08-13-2007 06:34 AM

Whenever testing the power supply to a lamp, disable the ignitor by removing the fuse or disconnecting one of the supply leads to the unit. If the voltage were to reach the triggering level for ignition while you are making the measurement, the ignitor could engage and destroy the meter. There is enough high frequency energy on the rectifier leads to destroy a meter, even at the output terminals of the power supply.

Remember, you may think you are smarter than the electricity but you are way slower!

KEN [Eek!]

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Mark Gulbrandsen
Resident Trollmaster

Posts: 16657
From: Music City
Registered: Jun 99

posted 08-13-2007 08:11 AM

quote: Michael Schaffer
Are you kidding, Mark?

quote:
And even if you're not, how many projection booths just happen to have the odd electric cattle prod lying around in the tool cupboard?!

No, not kidding! I learned this from an old RCA tech in Chicago many years back. It does work. They are pretty easy to find at any country store or feed supply.

Mark

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Stephen Furley
Film God

Posts: 3059
From: Coulsdon, Croydon, England
Registered: May 2002

posted 08-13-2007 08:27 AM

I've sometimes been able to start an old mercury or SOX (low pressure sodium) lamp that's near the end of it's life and not been used for a long time by giving it a bright flash of light from a flashgun. With difficult SOX lamps if you start them by this means and then let them run for a few hours they will usually start by normal means after they have been switched off.

[ 08-13-2007, 11:01 AM: Message edited by: Stephen Furley ]

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