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is out of circuit and amber notching light is extinguished the
weak field notches will be automatically inserted under the
control Of the accelerating relay. A series of ten (10) starting
resistances are provided therefore ten (10) separate notching
movements can be made in the low speed notches.
Position 4 (Run Up) This is the normal operating position and
gives the operator flexible control in each combination.
Position 5 (Transition) This position is used to achieve
forward transition only when the notching light (amber) is
extinguished and the accelerating handle is momentarily placed
in this position transition is effected. The accelerating
handle should then be placed in position 4 to give flexibility
of control.
3.
Regenerative Brake Handle
The Regenerative braking handle has two positions
"OFF" and "REGENERATIVE BRAKE"
The Regenerative braking handle can be operated only
when the Reverse lever is in the forward position and the
accelerating handle is in the " OFF" position. There is a hump
guide between the "Off" and the Regenerative brake positions.
The Regenerative braking effort is controlled according
to the angle position of the regenerative braking handle.
The detailed function of the Regenerative brake is described
under "Operating procedure".
Regeneration Brake Control
Regenerative braking can only be used if the reverser
handle is in the forward position.
The braking range is set to provide maximum to minimum
braking provided the current and weak field ratio limits are
not exceeded to cause unstable traction motor operation.
The maximum armature current limit of 900 amperes in
braking is gradually decreased to 690 amperes automatically
during a time interval of ten (10) minutes to prevent overheating of the traction motors. From the above it will be
noted that the braking effort will be gradually reduced after
the initial application even though the regenerative braking
handle is in a fixed position.