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Author Topic: Is there a way to up the open circuit voltage/Irem Rect Brad Allen Jedi Master Film Handler Posts: 688 From: Evansville, IN, USA Registered: May 2000 posted 05-19-2005 03:55 PM                     The Irem rectifier I have, I measure 78v open circuit. Rating plate shows 75v, so I assume it's within spec. Is there a way to increase this voltage? I understand that 100v is more desirable. Trying to cure hard starting of bulb.  |  IP: Logged John Walsh Film God Posts: 2490 From: Connecticut, USA, Earth, Milky Way Registered: Oct 1999 posted 05-19-2005 04:45 PM                     Most do not allow adjustment of the no-load voltage. 75V should be OK for a 1.6K - 2K bulb. Have you looked at other causes of hard starting, like the RA relay, etc.? I recently had an issue where the operator had turned down the current to save bulb life, but it was too low to provide enough current to get the bulb to light reliably.  |  IP: Logged Richard Fowler Film God Posts: 2392 From: Ft. Lauderdale, FL, USA Registered: Jun 2001 posted 05-19-2005 05:06 PM                     Besides the RA relay, since you have Xenex I units, you can change the zener diode on the auto-strike board for lower no load voltage.  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 05-19-2005 06:59 PM                        You can test the RA relay theory by TEMPORARILY unplugging the relay and connecting black wires together and red wires together. If everything works OK, then you know the relay was the problem. Just don't leave it this way....bulb life will be shortened. In my experience, I have never seen low open-circuit voltage as a problem with IREM.  |  IP: Logged Marin Zorica Jedi Master Film Handler Posts: 671 From: Biograd na Moru, Croatia Registered: May 2003 posted 05-21-2005 12:28 PM                     Can you even strike xenon lamp? What is current when is on? Is it normal? If isn't maybe one of diodes is dead? Also look at filter capacitor, maybe is bad, just try to put some capacitor in serial  |  IP: Logged Brad Allen Jedi Master Film Handler Posts: 688 From: Evansville, IN, USA Registered: May 2000 posted 05-21-2005 01:08 PM                     Ok, I"ll plead ignorance. What does RA stand for? Are you talking about the relay on the auto ignitor board? Yes, lamp will light, but can take 3-5 attempts at times even with a new bulb. It's always been this way. Cap's arn't very old.  |  IP: Logged Steve Guttag We forgot the crackers Gromit!!! Posts: 12814 From: Annapolis, MD Registered: Dec 1999 posted 05-21-2005 02:56 PM                     I believe that "RA" was just IREMs designation for relay. Most use "K" for relays or some use "RL" but those that work with IREMS know the "RA-Relay", often pronounced "rah-relay". It is there to help with the ignition of the lamp by switching in and out capacitance. A big clue to its failure is if the lamp strikes and immediately goes out (as the relay switches out).  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 05-21-2005 07:59 PM                     Brad, What exactly is your line voltage there? I've only had problems with IREMs no load voltage when the line voltage was low as in a brown out condition. During brown outs the current had to be upped to get em to start reliably and then quickly turned back down to normal current after ignition. Mark  |  IP: Logged Brad Allen Jedi Master Film Handler Posts: 688 From: Evansville, IN, USA Registered: May 2000 posted 05-22-2005 01:24 AM                     I'll have to check on the line voltage. It's been a while since I checked it and don't recall. Thanks all.  |  IP: Logged Brad Allen Jedi Master Film Handler Posts: 688 From: Evansville, IN, USA Registered: May 2000 posted 05-26-2005 02:58 PM                     Line voltage @ 3:30pm local time was 121.7  |  IP: Logged Mark Gulbrandsen Resident Trollmaster Posts: 16657 From: Music City Registered: Jun 99 posted 05-28-2005 11:01 AM                     Brad, That seems a tad low to me for that line voltage level.... I seem to remember these being around 95 to 100 volts no load. I gotta wonder if the relay board is bad. Mark  |  IP: Logged Brad Allen Jedi Master Film Handler Posts: 688 From: Evansville, IN, USA Registered: May 2000 posted 05-28-2005 12:49 PM                     I'll tear it apart and check out the relay board next wk after the holiday. Thanks Mark and all.  |  IP: Logged

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