Film-Tech Forum ARCHIVE: What interlocking model/brand is best?

This is topic What interlocking model/brand is best? in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

To visit this topic, use this URL:
https://ft-forum.com/ft/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=1;t=007976

Posted by Eric Robinson (Member # 2966) on 05-02-2006, 03:52 PM:

I need to install some interlocking hardware, but am unfamiliar with the available models and brands. I'm interested in finding out what might be the easiest to use/install, etc...

I will be interlocking some SPA-7 automations with each other.

Additionally, I will be interlocking some CNA-100 automations with each other.

One thing I'm curious about is what to do if one projector runs faster than the other? Does interlocking hardware regulate the projector speed?

Thanks [Wink]

Posted by Steve Scott (Member # 630) on 05-02-2006, 04:08 PM:

My experience with the CNA-100's was that they already contained the necessary interlock terminals & controls.

Posted by Eric Robinson (Member # 2966) on 05-02-2006, 04:15 PM:

Yes...I am mostly interested in the hardware between the projectors. Someone recommended Speco brand rollers and also a film accumulator if my projectors don't have sync motors.

I'm also trying to figure out the wiring between SPA-7 automations. The Instruction manual I have says the wiring must be present but does not describe the wiring.

Posted by Aaron Sisemore (Member # 145) on 05-02-2006, 10:44 PM:

quote: Eric Robinson
Additionally, I will be interlocking some CNA-100 automations with each other.

The CNA-100s should be interlock ready out of the box. All you have to do is wire the network cables between the automations to set it up.

quote: Eric Robinson
One thing I'm curious about is what to do if one projector runs faster than the other? Does interlocking hardware regulate the projector speed?

No it doesn't.

If your projectors are all the same make and model, and all have the same type of synchronous (1800 RPM) motors (not split-phase (1725 RPM) motors), then all you are going to need is some sort of accumulator rollers between each pair of projectors to catch any slack caused by small speed variations.

-Aaron

Posted by Eric Robinson (Member # 2966) on 05-03-2006, 02:21 PM:

According to my SPA-7 instruction manual:

quote:
The four wires required for sync operation are SYNC START, SYNC RESUME, SYNC FAILSAFE, and GROUND.

This is all the information provided other than a termination schedule. I would assume that I would connect it as follows:

Projector 1 Projector 2
...............................
SYNC START SYNC START
SYNC RESUME SYNC RESUME
SYNC FAILSAFE SYNC FAILSAFE
GROUND GROUND

Seems simple but, just wanted to see if anyone had any inputs on this. Thanks.

[ 05-03-2006, 04:21 PM: Message edited by: Eric Robinson ]

Posted by Jason Burroughs (Member # 68) on 05-03-2006, 07:04 PM:

Since you will be interlocking different automations, you may have to fall back on the old, tried and true 2 man interlock.

1....2....3....Go! on the motor switch (If you do this way, you HAVE to be there for the entire legnth of the show, not even a piss break - Murphy's law loves piss breaks)

In regards to hardware (rollers etc). SPECO and Kelmar make quality equipment and can't go too wrong with either one of them. You will need to have some sort of acumulator to compensate for any slight difference in motor speeds, as well as to keep tension on the failsafes of the 1st machine in the interlock.

Posted by Eric Robinson (Member # 2966) on 05-04-2006, 10:16 AM:

Actually I will be hooking the same models of automations to each other. I have one theatre building which has SPA-7 and a different theatre building which has CNA-100's.

Thanks for the heads up on the accumulator and the tension on the failsafe for the starting projector.

I was thinking of putting in some lever switches at the top and bottom of the accumulator which would trigger the projectors to both STOP in case the accumulator becomes too tight ot too loose. Has anyone else done this?

Posted by Steve Scott (Member # 630) on 05-04-2006, 12:47 PM:

I've always used the speco rollers in interlock setups. 9 out of 10, they did the job, but there is a fairly wide gap between keeper & main roller. But if they're all you've got, careful planning & spacing will keep the show running.

Posted by Monte L Fullmer (Member # 2797) on 05-04-2006, 12:58 PM:

STRONG has rollerbars and accumulators as well (never liked the split rollers of the SPECO hardware - film has a nasty habit of sliding in the splits) the STRONG accumulator, I think, is the best due to the "w" format like the platter accumulator.

Yet, Kelmar really is the all around best guidance hardware for both machinery and interlocking - large sealed bearing loaded rollers, and the long swingarm accumulator.

I've tied up 6 SPA-7 units and they work very well. You just tap in on the back board in the console with a fourwire cable in parallel with all 6 machines.

Since you have all STRONG booth, you should have those Bodines or Leeson motors - which are the syncronous type - on your setup.

Putting a micro shutoff in the accmulator is okey, but with the coasting of the machinery when power is dumped, really won't do you any good unless you're right there to catch the far machine that is pulling the whole string upward.

(Oh, do you know how to properly thread interlocks? pull all your film through the rollers and lace the farest machine from the payout platter first,and thread back to the payout platter. Then tighten all of the film travel. This way you'll never run short of film when threading..)

thx - Monte