22
Service and Maintenance
Models 2-120 and 2-240
Federal Signal www.fedsig.com
5.
Remove the four bolts holding the chopper rotor and armature to the stator. Lift out
the rotor and armature.
6.
Remove the lock nut and lock washer from the armature.
7.
Use a bearing puller to pull both roller bearings from the armature shaft.
8.
Use a hydraulic press to separate the armature from the chopper rotor.
9.
When installing a new armature, it may be necessary to change the electrical
connections of the field. Therefore, refer to the instructions included with the
replacement armature for the correct field connections.
10.
Install the replacement armature and reinstall the siren following steps 1 through 8 in
reverse.
To replace the field:
1.
Turn off the power to the siren at the disconnect switch.
2.
Remove the siren housing from the mechanism.
3.
Disconnect the electrical power wiring from the siren motor.
4.
Remove the siren mechanism from the mounting surface. If desired, the legs can also
be removed from the mechanism.
5.
Remove the field-retaining ring from the motor housing.
6.
Arrange two spacers consisting of 4 x 4-inch (102 x 102 mm) lumber or similar
material, approximately 5 inches (127 mm) apart on a solid work surface as shown in
Figure 7.
7.
Sharply rap the motor housing against the spacers several times until the field drops
out of the motor housing. The motor housing is aluminum die-casting. As a result, it
can be broken or damaged. Therefore, use caution to ensure that the motor housing
strikes the spacers squarely as indicated in Figure 7.
Figure 7 Model 2 Field Removal
"
