Film-Tech Forum ARCHIVE: Exciter Lamp voltage in Cinemaccanica CC-2500H Console

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Posted by Jason Burroughs (Member # 68) on 12-09-2002, 04:45 PM:

How do you adjust the voltage for the exciter lamp on a Cinemaccanica CC-2500H lamphouse, I have one console that that is producing low voltage and need to turn it up, but however there does not appear to be any way to adjust this.

Also have a V-8 in which the douser does not work at all. Mechanically everything appears to be OK. Everything is free moving, and once the projector is up to speed and the douser is opened by hand it stays open. This projector has the push-button, fire shutter type douser.

Also if anyone has a wiring diagram for a CC-2500H it would be greatly appreciated. I have emailed Cineamaccanica for help on these consoles before and never recieved any type of reply from them.

Posted by Richard Fowler (Member # 893) on 12-09-2002, 05:11 PM:

Talk to Sam, the tech in their office in California. Items such as serial numbers and the circuit you work for will help since there are many modifications to Cinemeccanica consoles. E-mail may be best in case Sam is out of the office. cinemec@earthlink.net

Posted by Gordon McLeod (Member # 33) on 12-09-2002, 05:25 PM:

If it is the older blue consoles there should be a pot right below the ampmeter for the excitor lamp current on the lower door.
If not the excitor supply is usulally on the back of the lower door on the operating side and it could have the pot there. It also provides the framing lamp supply

There are several different changeover arrangements on the vic8 a picture would be helpfull

Posted by Jason Burroughs (Member # 68) on 12-10-2002, 09:54 AM:

Richard,
The current chain is EFW, however this is a former GCC theater. I will get serial numbers this weekend when I am back there.

Gordon, there is no ammeter on the exciter lamp supply, at least hat I've been able to find.

I will work on getting some pics. However some are already available in the PICs page (see the GCC Furneaux Creek) These are the Blue consoles, this theater is an ex-GCC. The theater appears to have oppened sometime around 1983. Unfortunatly these machines suffer from years of abuse and neglect. The wiring harnesses on these consoles are a complete rat's nest as well.

The other issue that I have with these consoles is that there appears to be a problem with the auto-strike. When the lamp is first turned on, it will attempt to strike only once. If the ignition is not successful on this one attempt the lamp stays off and must be struck manually. The bulbs are Osram XBO-2000's with an unknown number of hours (at least 1000). Don't ask why the hours are unknown, as this is a lovely EFW theater.

Posted by Tim Reed (Member # 137) on 12-10-2002, 11:27 AM:

Jason, open the console door (where the rectifier is located), and on the inside of the door, about half way up and to the rear, is the exciter supply. It will have a big, round transformer at the top of this unit, and often several green led's on the board. Just about dead-center on this board is a small dial-looking potentiometer that is scaled from (either) 0 to 10 or 0 to 100 (can't remember). That's the exciter voltage. Take something like a Dolby tuning wand and turn it up there. Watch your exciter lamp when you do this, to make sure you are turning the correct control because there are a couple other adjustments on that board. But the exciter lamp control is the one that is closest to the center (as I recall).

The autostrike circuit is inside the igniter housing on those lamphouses. In later versions, it is potted inside the igniter. The quick solution is just to replace the igniter; which is a job in itself.

Let us know how you make out.

Posted by Jason Burroughs (Member # 68) on 12-10-2002, 12:12 PM:

Tim,

Nope the exciter supply is inside the door on the right hand side, towards the bottom, only type of switch dial or anything is CC and CA which appears to switch between DC and AC modes. I'll try to get a pic of it posted on Fri.

The ignitor appears to be a DX-5 model, not sure if that helps any

Posted by Tim Reed (Member # 137) on 12-10-2002, 01:10 PM:

To the rear of the door, I meant, when the door is open -- "right-side", okay.

Alright, if it's got the CA/CC switch (i.e. "current alternating/current continuous"), it's a little older than the one I described. I believe there is no adjustment on that, other than changing the taps on the transformer, but you shouldn't have to do that. (Humm, there might be like a 25W adjustable resistor, though.... it's been a long time since I saw one that old.)

Check your exciter lamp socket, to be sure you're not losing contact there. It's not a 9V-4A exciter, and is like 3.5-4V, the little skinny bulbs with the dimple in a straight base? Often, the tip contact of those sockets oxidizes and causes the bulb to glow dimly. That may be the problem. I've had luck with emery cloth on those... for a temporary fix until a new tip contact can be installed. Also check the connections to the socket proper.

If the igniter's mounted on the console sub-floor or wall, then it's easy to just change it out. On the later models, the whole lamphouse plenum has to come out to get to it. Also, check to make sure the nichrome wire is clipped OFF of the xenon bulbs. They have a tendency to cause the ignition pulse to arc to the reflector in that console.

Posted by Jason Burroughs (Member # 68) on 12-10-2002, 02:10 PM:

The exciter lamp is new (only new bulb I have on hand, only because it was left with equipment when previous tenant vacated or left behind by kind tech)
I have checked all the connections and they appear to be tight, didn't notice any corosion. The bulb has a smooth base with a dimple in it.

The igniter is mounted to the bulb plenum assembly. But keep in mind that I don't have any spares, and the owner is not interrested in buying any parts. So I just wanted to see if there were any adjustments that could be made.

Posted by Gordon McLeod (Member # 33) on 12-10-2002, 03:19 PM:

Early consoles used an external relay with a zenier diode.
If the ignitor is a squarish black box the autostrike is on a small circuit board inside it

Posted by Tim Reed (Member # 137) on 12-10-2002, 04:43 PM:

It's either the exciter socket, or the power supply is on the blink. I'll bet it's the socket or a connection, because switching to "CA" should give the bulb full brightness; I don't think there is anything else in the circuit at that point but the transformer (and, of course, all the connections along the way).

You might check for tight, clean connections at the supply and the switches... They also used quick-disconnect terminals for a lot of connections along the terminal strip inside the lower console door. Some exciter connections are made there, too. I have found those burned sometimes.

If you haven't already, try using the manual switch on the automation, in case the relay inside is pitted.

Most GCC houses had a spare exciter supply. If this isn't available, I would swap the suspect unit with one from another house. That would tell you for sure where the problem lies.

If the owner won't supply you with parts, then I wouldn't worry too much about it. There is only so much you can do with nothing. [Wink]

Posted by Jason Burroughs (Member # 68) on 12-10-2002, 04:58 PM:

switching to CA does give the bulb full brightness (and then some). I have tried the manual switch on the automation as suggested, same results. I will double check all the connections again next time I am there.

There is no working spare exciter supply in the theater. Come to think of it, we have no good spares of anything, so.....

Posted by Ken McFall (Member # 845) on 12-10-2002, 04:58 PM:

As Gordon says, if the ignitor is a square black box then it's an Irem unit which seems to be a standard fit now. Inside is a small circuit board which controls the auto strike.

It 'could' be that the auto strike has either never been connected because your automation effectivly provides a manual push of the strike button or maybe a wire has become detatched.

Clearly the srike unit is in itself working so check that out. There should be a link between terminal 4 & 5 on the strike unit itself. CHECK OUT THE TERMINAL NUMBERS AS I AM DOING THIS FROM MEMORY! Once bridged this will enable auto strike and the lamp striker will pulse on & off until the lamp strikes.

All that is happening is that the circuit board detects a high dc voltage when the lamp is not running and attempts to strike. Once the lamp is running the dc voltage drops to around 20-25v and the strike circuit is disabled.

Failing that the circuit board could be faulty. Its easy to replace and not expensive. Two screws remove the cover and the circuit board is just sitting in a small compartment with a single plug in connector.

I can check out the terminal numbers if you like.

Hope this helps.

Regards.

Posted by Jason Burroughs (Member # 68) on 12-10-2002, 05:26 PM:

The igniter is on a fiber board about 12-15 inches long and about 3 inches across. the components are exposed and not enclosed in a box, so it deffinatly does not appear to be an IREM unit (although the rectifier is).

Brad has graciously attempted to help me in the past with these units, however even he was unable to locate any documenation on these consoles.

Posted by Richard Fowler (Member # 893) on 12-10-2002, 05:39 PM:

The DX-5 is mounted on the side of the light module with a separate relay / adjustment pot. As these units are very old and some of the rubber grommets on the blower and other fastening points start to turn to mush, there will be some ignition problems as the bulb spark find other paths to travel other than the bulb. The cabling on the door will also turn brittle in the enviroment it is in and D.C. may not work as well as A.C. + the aging of the transformer. We have done recent rebuilds on these series of consoles in which we use a more modern ignitor / power supply and wire harness.

Posted by Tim Reed (Member # 137) on 12-10-2002, 06:58 PM:

If the exciter comes to full brightness in CA, then the external connections are okay. A component may be out in the exciter supply (like a regulator, if it has one), or a connection within.

I still don't know if that unit is adjustable or not, I keep thinking it's not, does anyone else know?

Richard, those consoles you rebuilt didn't happen to come out of Coral Square, did they? I remember they had those igniters there.

Posted by Richard Fowler (Member # 893) on 12-10-2002, 07:15 PM:

Ohio,Texas, New York.......

Posted by Gordon McLeod (Member # 33) on 12-10-2002, 07:27 PM:

On those ignitors there wasa octal socketed relay for the auto strike on some mounted on the lower door