(7) Move handle to No. 7 notch and all
e. If the locomotive can be operated with only one
throttle operator valves operate.
motor the test is very simple. Run the locomotive in the
forward direction for a short distance, reverse it and
(8) Close T1 by hand. M1, M2, M3 and M4
operate in the reverse direction. If the locomotive
close.
operates approximately the same in both directions the
(9) Release T1. M1, M2, M3 and M4 open.
connections are correct. Repeat with all other motors on
(10) Repeat (8) and (9) using T2 instead of T1.
the locomotive operating them one at a time.
(11) Return throttle handle to OFF. All P
f. If it is impossible to operate on one motor at a
contactors open. Throttle operator returns
time the following procedure will be followed. Oil the
to idle position.
track on which the locomotive is to operate spreading
(12) Repeat (1) to (11) with reverse handle in
the oil on both rails. Then operate the locomotive (on as
REVERSE and note that reverser throws
few motors as possible) on this section of track in the
to reverse. Other sequence should be the
forward and reverse directions until each of the motors
same.
operating has slipped its wheels in both directions.
(13) Note that the sander switch operates the
Repeat this same test on the other motors until all
sander valve corresponding to the
motors have slipped their wheels in both directions.
reverser position.
(14) If possible check that the stop buttons
likely to be encountered in making these tests.
operate the engine shutdown valves.
(1) The motor or motors operate the
(15) Check multiple unit feature by running the
locomotive in the direction indicated by
above test on a locomotive controlled by
the reversing lever. This indicates the
another.
Check the remote engine
correct connections.
stopping circuits for operation as
(2) The motor or motors operate the
described under "Multiple Unit Operation."
locomotive in the opposite direction to
If this is not possible, be sure wiring to
that indicated by the reversing lever. This
receptacles is checked by using a bell
can be caused by the reversal of leads to
ringer.
the reverser or by the motor being hung
on the opposite side of the axle from that
51. Testing Motor Rotation
assumed on figure 44. If the reverser
a. Every time the traction motor leads or the power
leads are interchanged, correct at the
terminals to the reverser are disconnected test the
reverser. If the latter, interchange the
motors for correct rotation when reconnected.
motor field leads at the motor lead
connectors and repeat tests.
b. This test is very important as it is possible for a
locomotive to apparently operate correctly in either
(3) One motor tending to drive its axle in one
direction and still have been incorrectly connected which
direction and another trying to drive in the
may eventually produce serious and costly motor
opposite direction.
If reverser wiring
trouble.
agrees with figure 44, interchange the
field leads of the proper motor so the
c. For example, if a field and armature lead of a
locomotive will operate according to the
motor are interchanged the motor would operate
reverser handle position.
correctly when the locomotive was moved in one
direction but in the opposite direction the motor field
(4) A motor may operate the locomotive
would be cut out by the action of the reverser. If this
correctly in one direction but slowly or not
condition were to continue in service for some time
at all in the opposite direction. This is
before being found it would probably result in a "roasted
usually caused by the interchanging of an
out" motor.
armature and field lead. Such an error
will give correct operation in one direction
d. To make this test, operate the locomotive on the
but will cut the field out of the circuit
least possible number of motors. This may mean
entirely in the opposite direction. If the
opening cutout switches or shutting down a power plant.
two motors are tested at one time,
23
