Mount generator in test stand or on bench, making certain
generator is well secured.
Connect single-pole (single-throw switch with current-carrying
capacity in excess of 3000 amperes to positive (+) terminal of 28-volt
dc power source.
Connect in parallel from other side of switch a resistor with
O.1-ohm, 400-ampere rating and a rheostat with minimum rating of 10
ohms , 15 amperes.
Connect rheostat to terminal A of generator.
Connect resistor to terminal B of generator.
Connect negative terminal of 28-volt dc power source to
terminal E of generator.
Rotate rheostat to minimum resistance reading, and close
switch to energize. generator.
Generator should start and run as a
motor in normal direction of rotation, counterclockwise when facing
If rotation is clockwise, check connection from power
two connections are reversed.
Adjust rheostat until armature develops speed of approximately
Run generator for 3 hours to polish brush seats on commutator.
After run-in remove one brush assembly at a time, and inspect brush
Each brush should show polished seating area of 90
percent in axial direction and 100 percent in rotational direction
If brushes are not properly seated, continue run-in
until properly seated, making brush inspection periodically.