TIMER for MODEL 24L
WALL MOUNT DISPENSING SYSTEMS
General Description:
The timer is a self-contained (frame mounted) timer of the repeating cycle type. It is mounted on the lower control
panel of the Jackson Dishwashing Machine to control the automatic functions of this machine. It consists of a clock
motor which operates on 60 cycle, 110VAC. In addition to the clock motor, the timer also contains a driven cam
arrangement which operates seven micro switches.
Principle of Operation:
The timer controls various operations of the automatic washers as per wiring diagram for each machine; however,
the timing cycle and the micro switches are the same for each model. The time for One Complete Revolution of the
cam shaft is approximately 180 seconds, allowing one wash and one rinse operation for the complete revolution of
the cam shaft. The Micro Switch nearest the timer motor is the hold circuit. The Micro Switch second from the timer
motor controls the wash/rinse cycle. The Micro Switch third from the timer motor controls the detergent dispensing
cam. The Micro Switch fourth from the timer motor controls the drain cycle cam. The Micro Switch fifth from the
timer motor controls the water fill solenoid cam. The Micro Switch sixth from the timer motor controls the rinse
additive dispensing cam. The Micro Switch seventh from the timer motor controls the sanitizer agent cam.
Service Instructions:
CAUTION: Always remove the power to the machine before working on the control panel or while servicing
the components in the door panel. All electrical checks should be made by qualified personnel.
Timer operation can be observed after removing the machine's kickplate by loosening the two screws holding it.
If it is determined that the timer is defective, it is recommended that a new timer be installed. If a new timer is not
available, limited field maintenance can be accomplished by changing the micro switch.
A frozen contact on a micro switch will be indicated by one function being executed all the time or the absence
of a click when the switch arm is activated.
To Replace Micro Switch:
1. Remove all wires from the timer, properly tag them to assure proper replacement.
2. Remove the screws which hold the timer to the control panel.
3. One screw holds the micro switches, cams and actuating arms in the frame. This screw is seen on the
side opposite the motor. Remove this screw.
4. The unit can now be taken apart and the defective micro switch replaced.
5. Reassemble.
Note: The flanges on the cams are such that they only mesh in one direction.
The timers cam drive system is equipped with a clutch to enable one to view the operations of the cams
and micro switches. Remove power to machine before touching timer. Rotate cams by turning with fingers;
cams will turn in one direction only. Do not force them. As cams actuate switches, listen for the 'click' of
the switch or test the switches with an ohmmeter.
