TM 55-2210-223-12
TO 45A2-2-14-41
2-23. LOAD LIMITS
a.
Keep the locomotive within proper load limits.
The load meter is connected to measure one-
half the output of the main generator. The
continuous operating limit of the locomotive is
1200 amperes (600 on meter). Any reading of
the load meter in excess of the continuous
operating limit indicates an overload.
b.
Operation in overload range is permissible as
long as the following time limits are not
exceeded:
Range
Time
0 to 1200 amperes (0 to 600 on meter)
Continuously
1200 to 1400 amperes (600 to 700 on meter)
20 min
1400 to 1600 amperes (700 to 800 on meter)
10 min
1600 to 1920 amperes (800 to 960 on meter)
5 min
c.
When the time limit for that overload range is reached, the generator and motors are at their maximum allowable
temperature; to avoid severe damage from overheating, allow excess heat to dissipate by one of the following
methods:
(1)
With load cut off and engine idling, allow a cooling period of 15 to 30 minutes, after which operation in any
one of the overload ranges is again permitted with cooling period to follow.
(2)
Reduce load to continuous range on the dial and continue operation in this range.
2-24. GROUND RELAY ACTION
CAUTION
Repeated tripping of the ground relay, accompanied
by unusual noises such as continuous thumping or
squealing, may also be an indication of serious
traction motor trouble that must be investigated at
once.
a.
If a ground occurs in the high voltage circuit, the ground relay will trip and the engine will return to idle.
2-39
