Film-Tech Forum ARCHIVE: Solenoid for Rentech zipper

This is topic Solenoid for Rentech zipper in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Matt Close (Member # 996) on 05-01-2002, 08:06 PM:

I have a Rentech CD-200 zipper with a burnt out solenoid ... due to crap sticking relays in the crap CFS switching board!!

Anyway, CFS and Rentech are long since gone ... aren't they? (correct me if I'm wrong) ... so where can I get a replacement part?
It is a P&P Industries solenoid model# S4-25A-220 {3009}

Also can anyone reccomend good zipper units for my Monee (please don't flame me) projectors? I have a few projectors in the throws of re-furbishment but they all lack the zipper.

Posted by Richard Fowler (Member # 893) on 05-01-2002, 08:44 PM:

Kelmar ECC-35 available in 110 and 220 VAC models would be a suitable full replacement changeover OR you could contact Dick Niccum ( Mr. Rentec himself ) at www.lightingimages.com / FAX 909-981-3071.
Richard Fowler
TVP-Theatre & Video Products Inc. www.tvpmiami.com

Posted by Paul G. Thompson (Member # 655) on 05-01-2002, 08:46 PM:

Since the Monee is a knock-off of a Century, I would presume the Century Zipper would work just fine. I think Aaron Sizemore runs Monee's, and he could tell you for sure.

Posted by Ken Layton (Member # 133) on 05-01-2002, 09:18 PM:

Yes, you should be able to use the Century CV-653 ZIPPER changeover and you can buy it from Edward H. Wolk Company (www.edwolk.com) thru any theater dealer. It costs around $200.

Posted by Aaron Sisemore (Member # 145) on 05-01-2002, 10:13 PM:

Paul, All of the Monees are out of service now. Wanna buy one?

The CFS changeover is exactly the same as the Strong or Kelmar unit. Call either of them or Dick Niccum at LIT for replacements.

LIT also does support some CFS equipment (dimmers, autos, etc).

-Aaron

Posted by Paul G. Thompson (Member # 655) on 05-01-2002, 11:56 PM:

Aaron: Not only NO, but HELL NO!

I have a load of Cineshitties...do you want one? They have no movements, though. All the movements were fried because some dum-dum heads didn't know what a can of oil was.

Matt, if the unit is the same as a Kelmar, the coils run about 20 to 30 bucks, somewhere in that area. Gordon suggested putting a 100 watt light bulb in series with the coils....that will keep them from burning up in event of a sticky relay contact.

Posted by Matt Close (Member # 996) on 05-02-2002, 02:06 AM:

Paul ... A light bulb... interesting idea! Why didn't I think of that. Apparently they have burnt out several coils here over the years through sticky relay contacts. I was thinking of either putting in physically larger relays, or maybe a couple of slow-blow fuses.... what do you guys think? Light bulbs, relays, or fuses?

Posted by John Pytlak (Member # 331) on 05-02-2002, 06:15 AM:

The filament of the cold light bulb has a very low resistance, allowing the high current needed to activate the solenoid. If the circuit stays on, the bulb will just light up (hot filament has higher resistance), limiting the unwanted current through the solenoid.

------------------
John P. Pytlak, Senior Technical Specialist
Worldwide Technical Services, Entertainment Imaging
Research Labs, Building 69, Room 7525A
Rochester, New York, 14650-1922 USA
Tel: +1 585 477 5325 Cell: +1 585 781 4036 Fax: +1 585 722 7243
e-mail: john.pytlak@kodak.com
Web site: http://www.kodak.com/go/motion

Posted by Paul G. Thompson (Member # 655) on 05-02-2002, 08:10 PM:

Matt, the coil will protect the fuse by blowing first. Use the light bulb. Another advantage of the bulb is that if it stays lit, you know you have a problem.

Posted by John Pytlak (Member # 331) on 05-03-2002, 10:18 AM:

Might it also be possible to use Thermistors, similar to the circuit used for automatic degaussing coils?:
http://www.nichicon.co.jp/english/seihin/pdfs/e-po_tv.pdf

These devices allow a high current when cold, and quickly reduce the current.

Posted by Matt Close (Member # 996) on 05-04-2002, 07:40 AM:

I'm curious ..... does anyone actually 'have' light bulbs installed to prevent coil failure?

Posted by Paul G. Thompson (Member # 655) on 05-04-2002, 12:53 PM:

Matt, we had light bulbs installed in the change-over circuit at the old Lido Theatre in Mount Vernon. That booth ran for the better part of 40 years without a Weaver Douser coil failure.