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Author Topic: My rectifyer is abusing my sound-rack
Michael Brown
Phenomenal Film Handler

Posts: 1522
From: Bradford, England
Registered: May 2001


 - posted 03-21-2003 11:43 AM      Profile for Michael Brown   Email Michael Brown   Send New Private Message       Edit/Delete Post 
hmmmmm

nice.

I noticed a few weeks ago that when striking the lamp, the sound system reset. (momentary power loss). Interesting yet I didn't really think anything of it. (we have 2 breakers on two separate fuses)

We had a film last night. Power up the sound rack. Play non-sync for about 25 minutes, then at about 8pm we powered up the rectifyer and struck the lamp...... and fried 2 cards in the CP-55. [Frown]

My engineer has just been and cards are out to repair and he loned us some cards.

So. The basic plan that me and my deputy have come up with is that we will simply strike the lamp before we power up the soundrack. Hopefully that should work.

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Darryl Spicer
Film God

Posts: 3250
From: Lexington, KY, USA
Registered: Dec 2000


 - posted 03-21-2003 06:25 PM      Profile for Darryl Spicer     Send New Private Message       Edit/Delete Post 
The big question is why is it that everytime you power the rectifier you burn something up in your soundrack?

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Daryl C. W. O'Shea
Film God

Posts: 3977
From: Midland Ontario Canada (where Panavision & IMAX lenses come from)
Registered: Jun 2002


 - posted 03-21-2003 06:34 PM      Profile for Daryl C. W. O'Shea   Author's Homepage   Email Daryl C. W. O'Shea   Send New Private Message       Edit/Delete Post 
I'd start checking your electrical grounding, especially around the ignition circuits. Electricity doesn't always go straight (down) to ground -- if you've got a small short to ground in your ignitor it may be finding its way into your rack.

In the meantime I hope your ignitor doesn't automatically strike if the lamp goes out. If it does and your rack runs on one 15 amp breaker, you might want to find yourself a good long 10/3 extension cord.

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Matt Hale
Expert Film Handler

Posts: 123
From: Vancouver, Canada
Registered: Dec 2002


 - posted 03-21-2003 06:38 PM      Profile for Matt Hale   Author's Homepage   Email Matt Hale   Send New Private Message       Edit/Delete Post 
Check your grounding. I'm not much of an electrician, but I know "seperate circuits" rarely means "seperate grounds" and I have run into all sorts of problems with audio gear sharing ground points with other equipment. Even different electrical panels in different parts of the building may be grounded together. Its possible something in your rectifier or lamp igniter is momentarily shorting to ground, and jolting your sound rack that way.

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John Hawkinson
Film God

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


 - posted 03-21-2003 10:12 PM      Profile for John Hawkinson   Email John Hawkinson   Send New Private Message       Edit/Delete Post 
Err, I would be wary of drawing many conclusions from what seems to have happened here. No matter how poorly grounded the rectifier/lamphouse or the CP55 might be, frying cards should not happen--what cards were they and how did they fail?

I don't think you have any reason to believe the failure is more less likely with the CP55 powered off...

--jhawk

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Gordon McLeod
Film God

Posts: 9532
From: Toronto Ontario Canada
Registered: Jun 99


 - posted 03-21-2003 10:44 PM      Profile for Gordon McLeod   Email Gordon McLeod   Send New Private Message       Edit/Delete Post 
I think you have one of theose converted lamphouses if my memory of the pictures is correct
An ignitor that is improperly grounded or supressed can generate sufficient noise to reset or even damage some other electronics
get a competent engineer in to check for the source of the emi

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Paul G. Thompson
The Weenie Man

Posts: 4718
From: Mount Vernon WA USA
Registered: Nov 2000


 - posted 03-21-2003 11:23 PM      Profile for Paul G. Thompson   Email Paul G. Thompson   Send New Private Message       Edit/Delete Post 
I agree with Gordon, Matt, and Daryl.

Once I saw the "fireworks fly" on ignition with an ORC lamp that was not properly grounded.

Make sure all your equipment is properly grounded at all times.

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Darren Briggs
Master Film Handler

Posts: 371
From: York, UK
Registered: Dec 2001


 - posted 03-22-2003 06:50 AM      Profile for Darren Briggs   Author's Homepage   Email Darren Briggs   Send New Private Message       Edit/Delete Post 
MIchael,
Who installed your gear? Was is it Jim's friend by chance???
I can recomend a few engineers for you or call acrros myself on a day of if you need some advice.

Darren

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Bruce Hansen
Jedi Master Film Handler

Posts: 847
From: Stone Mountain, GA, USA
Registered: Dec 1999


 - posted 03-22-2003 04:25 PM      Profile for Bruce Hansen   Email Bruce Hansen   Send New Private Message       Edit/Delete Post 
Check for a loose neutral. If a neutral is loose somewhere, unbalanced loads on the (hot) legs can cause strange voltages between the legs and the (loose) neutral. If you have a volt meter, check this.

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Neil McGovern
Film Handler

Posts: 35
From: Sheffield, UK
Registered: May 2002


 - posted 03-24-2003 02:57 PM      Profile for Neil McGovern   Author's Homepage   Email Neil McGovern   Send New Private Message       Edit/Delete Post 
Another thing that may be worth checking (if you have 3 - phase power) is that they run off different phases.

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Michael Brown
Phenomenal Film Handler

Posts: 1522
From: Bradford, England
Registered: May 2001


 - posted 03-24-2003 03:04 PM      Profile for Michael Brown   Email Michael Brown   Send New Private Message       Edit/Delete Post 
I'm gunna get the guy who we bought it off (and who did the install) to come take a look.

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