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Author Topic: Eprad Co-operator continues to cycle - FIX Kenneth Wuepper Phenomenal Film Handler Posts: 1026 From: Saginaw, MI, USA Registered: Feb 2002 posted 05-06-2007 05:18 PM                     Just finished servicing an old Co-operator for a single screen house. The drum would continue to coast and then recycle the projector, house lights and curtains continuously. The first thought was the microswitch for the drum motor. NOT! By applying a small drag on the cam shaft, it was apparent that the motor shaft was "coasting" after the power went off. Refer to the diagram of the unit and discover that Eprad anticipated this problem and solved it by adding a DC brake for the drum motor. A 1N4005 diode and 2.2K resistor are in series and across the run contacts of relay KS for the drum motor. The resistor had failed and so the motor was free to coast past the stop detents. Installing a new diode and resistor (2 Watt Carbon) fixed the problem. These components are buried at the bottom of the chassis pan and are soldered to a terminal strip there. If you have this problem, you will notice that the resistor is enclosed in shrink wrap with the diode sticking out one end. Hope this is helpful. KEN  |  IP: Logged Jack Ondracek Film God Posts: 2348 From: Port Orchard, WA, USA Registered: Oct 2002 posted 05-07-2007 04:21 AM                        Thanks for the info on that, Ken. I still take care of a couple of them. I just figured that with the gearing, and lack of any flywheel on that clock motor, coasting wouldn't be an issue.  |  IP: Logged Tim Reed Better Projection Pays Posts: 5246 From: Northampton, PA Registered: Sep 1999 posted 05-07-2007 05:49 PM                       Oh, it does coast. Very much so.  |  IP: Logged Louis Bornwasser Film God Posts: 4441 From: prospect ky usa Registered: Mar 2005 posted 05-07-2007 08:07 PM                        I am proud to say....."All of my Co-operators are no longer required to Co-operate!!!" Louis  |  IP: Logged

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