Motor Drive Belt And Stepper Motor - Ametek 7550 Operating Manual

3-14 SECTION 3 – MAINTENANCE AND SERVICING

Motor Drive Belt and Stepper Motor

The motor drive belt tension is set by loosening the motor bracket mounting screws and
sliding the motor assembly. The belt tension must not be excessive, approximately 0.25 -
0.50-inch of deflection halfway between the motor and magnetic drive centerlines is
sufficient.
The stepper motor is not serviceable; the motor is replaced as a unit once the pulley and
mounting bracket are removed.
Use the following procedure to replace the motor drive belt:
1. Remove the covers from the instrument.
2. Remove the Top Electronics Assembly (7500-3003) after disconnecting the marked
cables and 1/4-inch tube connections.
3. Remove the top panel.
4. Remove the Electronics Module Assembly (7500-3002).
5. Disconnect the two cables to the motor.
6. Loosen or remove the four bolts that retain the motor assembly to the base plate.
Remove the motor assembly if the motor must be replaced.
7. Remove the four bolts that retain the vessel mounting flange to the base plate.
8. Remove the centerline thermocouple from the bottom of the vessel.
Figure 46 - Stepper Motor and Pulley