Film-Tech Cinema Systems
Film-Tech Forum ARCHIVE


  
my profile | my password | search | faq & rules | forum home
  next oldest topic   next newest topic
» Film-Tech Forum ARCHIVE   » Operations   » Film Handlers' Forum   » Power supply

   
Author Topic: Power supply
Denis Tussiau
Film Handler

Posts: 2
From: Maharepa Moorea french polynesia
Registered: Dec 2011


 - posted 12-17-2011 02:09 PM      Profile for Denis Tussiau   Email Denis Tussiau   Send New Private Message       Edit/Delete Post 
Hi
I try to made a power supply for a xenon lamphouse 1600w USHIO.(the old one is out of order )
I have an igniter Irem AS 8030 with a relay board for auto mode,Of course the 1600w lamp in the projector( transport veronese LX1600)
I had bought 2 switching power supply working in paralel 21 v 27A each(21V AND 54A both) SO The igniter strike well when switched manualy,but in auto mode the relay board need at least 80v(relay is 77V DC)
There is good srtike but after nothing happened.I think because i need boost voltage and current?
My question is .How made the boost voltage 80volts.The power supplys deliver on load or no load always 21volts
is it possible to something? made a parallele boost board ?
regards
merci
den

 |  IP: Logged

Dave Macaulay
Film God

Posts: 2321
From: Toronto, Canada
Registered: Apr 2001


 - posted 12-17-2011 10:28 PM      Profile for Dave Macaulay   Email Dave Macaulay   Send New Private Message       Edit/Delete Post 
Powering a xenon lamp isn't totally simple, but your way might work. The biggest difficulty is that most power supplies are voltage regulated while a xenon supply must be current regulated. For a boost supply you can use an independent low current ~100VDC power supply isolated from the main one (one of the supplies must be powered through a true transformer, not an autotransformer - switching supplies are not always isolated). You use a blocking diode (sized to carry the full lamp amperage) at the output of the main supply, and wire the boost supply in parallel with the main one but "past" the blocking diode. Once the lamp strikes, the boost supply output will be loaded down to the xenon lamp voltage so it has to be designed to allow that.
Adding a decent sized paralleled capacitor to the main power supply output, and a large series inductor as well, will improve striking and reduce ripple.
Check the schematic for an old Strong 2kW single phase passive rectifier - this is how they work.

 |  IP: Logged

Marin Zorica
Jedi Master Film Handler

Posts: 671
From: Biograd na Moru, Croatia
Registered: May 2003


 - posted 12-18-2011 05:51 PM      Profile for Marin Zorica   Email Marin Zorica   Send New Private Message       Edit/Delete Post 
Also you do not need use booster diode if you use capacitor for gigher voltage, (150V DC)and resistor in series with it to limit start up current, then after striking lamp on you can short resistor via relay, this way you won't have big loses on booster diode, but you must check that main rectifier diodes can take 150 V or more so that booster voltage which is around 100V don't kill em. In fact you can made power supply for xenon lamp, i did few od them, some were my own smps, and some were used other smps.....easyest way to regulate current is to have shunt where you will take voltage which is directly proposite to lamp current.

 |  IP: Logged

Dave Macaulay
Film God

Posts: 2321
From: Toronto, Canada
Registered: Apr 2001


 - posted 12-19-2011 12:22 PM      Profile for Dave Macaulay   Email Dave Macaulay   Send New Private Message       Edit/Delete Post 
Marin describes the way many European lamp supplies like Irems work, it's a good system. You will still need a power supply for the boost voltage.
A shunt is for measuring current. It won't regulate it. The issue is that almost all standard switching power supplies you can get - Denis specs his at 21VDC - are voltage regulated, supplying as many amps as required to maintain the set voltage. A xenon lamp need a current regulated supply, giving whatever voltage is required to maintain a set current. It is not a trivial task to convert a voltage regulated supply to current regulation. There are options, like adding a saturable reactor in the lamp circuit, but none I know of are simple. The reactor chokes are not stocked at many (if any) shops.
Except for the fact that Denis is a few thousand miles from them, buying a cheap used rectifier removed for a D-cinema conversion would be his best option. Probably that's the best plan regardless.

 |  IP: Logged



All times are Central (GMT -6:00)  
   Close Topic    Move Topic    Delete Topic    next oldest topic   next newest topic
 - Printer-friendly view of this topic
Hop To:



Powered by Infopop Corporation
UBB.classicTM 6.3.1.2

The Film-Tech Forums are designed for various members related to the cinema industry to express their opinions, viewpoints and testimonials on various products, services and events based upon speculation, personal knowledge and factual information through use, therefore all views represented here allow no liability upon the publishers of this web site and the owners of said views assume no liability for any ill will resulting from these postings. The posts made here are for educational as well as entertainment purposes and as such anyone viewing this portion of the website must accept these views as statements of the author of that opinion and agrees to release the authors from any and all liability.

© 1999-2020 Film-Tech Cinema Systems, LLC. All rights reserved.