AEC Colortronic MSH Series 2039 - Manual (Page 26)

C Series Granulators Maintenance 26 of 53
5-6 Adjusting the Jackscrew Setpoints
Proper adjustment of the two machine-mounted jackscrews is important to performance and
safety. Improper settings can result in premature failure of the jackscrews.
Caution! To avoid severe damage to the jackscrews, be prepared to shut them down
immediately when the chamber or cradle is motionless for any reason while
the motors are running. This condition can occur when the chamber or
cradle jams on debris or when the chamber or cradle reaches the end of its
stroke, whether on the opened or closed end of the stroke.
Caution! Allow the jackscrew motor to come to a complete stop, and wait at least 5
seconds before reversing the motor. The jackscrew and other components
may be severely damaged if the jackscrew motor is reversed before it has
completely stopped.
Testing the Mounting Bracket Limit Switch
If debris is preventing the cutting chamber from closing, the mounting bracket limit switch
should be tripped. When this switch trips, the electrical current to the jackscrew motor is
interrupted, stopping the motor. If the switch does not trip, it needs to be adjusted. If the
switch has tripped, but the motor continues to run, then the switch may be defective, and/or
the remaining electrical circuit will need checking by an electrician.
Use the following procedure to check the mounting bracket limit switch:
1. Place a 4” x 4” x 12” (100 mm x 100 mm x 300 mm) wood block on its 4” (100 mm)
side between the mating surfaces of the cutting chamber.
2. Carefully close the chamber until it bears on the wood block with some pressure and
check that the limit switch shuts off the jackscrew motor. Be prepared to stop the
jackscrew at the control panel switch in the event that the mounting bracket switch is
not properly set.
3. Open the cutting chamber and close it on the wood block again to verify the switch
operation. If the switch is properly set, the jackscrew motor shuts down immediately.
4. If the operation is not satisfactory, adjust the limit switch as directed in the following
procedure.
Adjusting the Mounting Limit Switch
Use the following procedure to adjust the mounting bracket limit switch:
1. Remove the sheet metal cover.
2. Loosen the two screws on the limit switch mounting plate.
3. With the chamber open, adjust the plate so that the limit switch plunger is within 1/8”
(3 mm) of the machine base plate.
4. Test the limit switch as directed in the above procedure.
5. If the operation is satisfactory, replace the sheet metal cover.