Specifications

RailCorp Infrastructure Engineering Manual – Signalling

Maintenance Manual

Electric Point Machine Westinghouse Style M70 MKIII TMG E1583

4.1 Motor

4.1.1 Description

The point machine is fitted with a plug-connected series-wound motor, as shown in

Figure 4.1.1. The split field enables a regenerative braking circuit to provide snubbing

at the end of the stroke. The plug connector is indexed to prevent use of a wrong type

motor. If required, the machine can also be fitted with a 110V DC, AC immune

permanent magnet motor.

4.1.2 Removal and Replacement

1. Unplug the lead from the terminal board.

2. Remove the two bolts from the baseplate.

3. Slide the motor towards the end of the machine until the spur gear disengages

from the gear cluster and then remove the motor.

4. Replacement involves the above procedures in reverse order. Care should be

taken to ensure that the spur gear meshes properly and that the location spigot

seats properly before bolting down.

4.1.3 Overhaul

The operation of the motor should be observed during normal monthly maintenance

visits. If it shows signs of abnormal noise, slackness in the bearings or heavy burning

of the commutator, the motor should be exchanged.

Issue Date: 1 December 2009 Uncontrolled when Printed