Hello, Does anyone have a wiring diagraham for a ITR master with the two weights and 110 motor? Thanks, Randy
The circuitry to operate the winding motor on IBM weight driven master clock has got to be very simple especially when the single power source is 120 volts AC. It could get a little more complicated when the clock was made for use on 220 Volts AC such as those made for the World-Trade market or for low voltage battery supply. The winding motors used include 24 volt DC shunt wound motors, 24 volt AC motors as well as 120 VAC motors. Please be more specific as to the kind if problem you are experience with the IBM Weight driven master clock. Looking back through your Message Board posts, I see that the serial number of an IBM Master clock you've provided earlier, is not a known US Domestic IBM product, thus a wiring diagram may not be available. Some photos of the inside the case and the top and back of the case showing the wiring may help. i'm certain we can help.
Eckmill, You have seen how long ago I started on this clock. I finally purchased the bearings that I needed, made a pendulumn, refinished the case since this one had been painted, and cleaned and reassembled the works. I did not take a photo of the wiring or make any drawing to reference. Now I have no wiring at all. I am concerned about ruining the electric motor. The clock is at work and on Monday I can take some pictures. Thanks.
Randy, the winding motor circuit on the 120 Volt AC IBM weight driven master clock is no more complex than a simple desk lamp circuit. The circuit begins with the plug at the end of the cord and ends at the motor but half way to the motor the cord splits with one wire connected directly to the motor, the other wire splits off, terminating at the fan gear switch normally open connection. The other screw terminal on the fan gear switch is the operating contact of the switch. A wire from the operating contact on the fan gear switch then connects to the other connection of the winding motor. As said earlier, a photo of the interior of the clock would be helpful. Some small AC electric motors are simple two wire, others have both a field and armature windings (4 wires) which may have either internal or external terminations. The fan gear actual switch is mechanically a toggle switch, not momentary; it has two states....on and off. It is operated mechanically from the fan gear. Make sure you understand how the weight winding drum operates the fan gear and that you are familiar with the lock-out device which prevents the weights from falling when the clock movement is removed from the case. I can understand your concern about spoiling the motor as they are no longer available new and scarce if used but Randy, these motors have a nameplate describing their character. Along with your photos, include a word-by-word description of the motor name plate.
