Tennant 6200E, Руководство по обслуживанию, Страница: 188 / 222

ELECTRICAL
4-68
6200E 330415 (6--99)
PROPEL MOTOR CIRCUIT
The propel motor controller is used to control the
speed and direction of the propel motor. The
controller also turns on the hourmeter, main brush
motor, and vacuum fan motor while the vehicle is
in motion.
Electrical components used to control the
propel motor:
M1 main contactor, FU--1 80 amp fuse, 1242
motor controller, Propel motor, Propel foot control,
Seat switch.
There are three circuits needed to make the
propel motor run:
1. Power Circuit. (see Fig. 4)
A). Armature: Current flows from battery
positive to the M1 power contacts, through the
80--amp fuse FU--1, and then to the B+ terminal of
the motor controller. Current continues to flow
from the B+ terminal to A1 and through the
armature of the propel motor. From the negative
side of the propel motor A2, current flow
continues to M-- at the controller. To complete the
path back to the battery, the controller uses a
transistor like a switch to pulse the connection
between M-- and B-- at the controller. The
duty--cycle or on time for each pulse determines
the speed of the motor.
B). Field: The motor controller automatically
adjusts the DC current level of the motor wound
field to control the torque/speed ratio. The field
current profile is programmed into the controller at
the factory and is not user adjustable. At lower
speeds, the field current is higher to provide more
torque. To get higher speed with less torque, the
field current is adjusted lower. In addition, the
motor controller reverses the polarity of the field
current to change direction of the motor rotation.