Vehicle Operation; Vehicle Operation - Toro Workman GTX Electric & Lithium Service Manual

Vehicle Operation

The Workman GTX Electric electrical system uses a 48
volt battery pack, an electric traction motor, a vehicle
controller and numerous other electrical components to
allow vehicle operation.
Eight, 6 volt, advanced deep cycle batteries that are
connected in series provide current for a 48V, brushless,
high torque, AC inductive traction motor, the vehicle
controller and vehicle accessories. The batteries are
discharged as the vehicle is used so charging the batter-
ies after using the vehicle is necessary. A battery dis-
charge indicator on the dash provides the operator with
information on battery charge level. Demands on the ve-
hicle during use (speed, payload, incline use), battery
condition (age, charge level), ambient temperature and
vehicle condition will all put constraints on how long a
vehicle can be used before the batteries are in need of
recharging.
IMPORTANT: When connecting the battery pack in
the 48 VDC system, make sure that battery polarity
is carefully checked. System damage can occur if
batteries are not connected correctly.
The Workman GTX electrical system is an isolated sys-
tem so the vehicle frame is not used for any ground con-
nections. Before performing any electrical service, it is
recommended to open the vehicle battery circuit by dis-
connecting the conductors between the battery pack
and vehicle components (see Opening Battery Circuit in
the General Information section of this chapter). This will
prevent unexpected component operation when per-
forming service on the vehicle.
The electric traction motor directly drives a double re-
duction, high torque transaxle with integral differential.
Operator inputs for forward/reverse, supervision speed
limit switch position and accelerator pedal position are
used by the controller to determine needed electrical
power for the traction motor.
The traction motor is protected from overheating by a
thermistor (thermally sensitive resistor) that resides in
the motor housing. If unsafe motor temperature is
sensed by the thermistor, the controller will limit vehicle
speed and torque until the motor temperature reduces
to a normal level.
Electrical System
The vehicle controller is a sealed electronic logic device
that uses inputs from several vehicle components to
control motor speed and direction. These inputs include
several switches (key, direction selector, supervision
speed limit, parking brake), the traction motor thermistor
(temperature), the traction motor encoder (speed sen-
sor), the accelerator pedal and the vehicle main contac-
tor (solenoid). The controller also provides regenerative
braking to assist in slowing the vehicle whenever the ac-
celerator pedal is released. The controller has fault
detection capabilities to help identify system problems.
Battery current is available to the controller whenever
the key switch is ON which energizes the main contac-
tor. A high current fuse mounted to the controller pro-
tects the 48 VDC circuits.
The Workman controller also limits roll away speed in
instances when the vehicle begins to move (roll away)
after being stopped. On an incline and with the key
switch in the ON position, if the vehicle starts moving, re-
generative braking will limit vehicle speed.
Vehicle accessories (headlights, USB charge port, op-
tional reverse alarm and optional lights) are operated by
a 12 VDC system that is powered by a 48 VDC to 12
VDC converter mounted under the dash panel. These
vehicle accessories receive current for operation when
the key switch is ON. The 10 amp fuse in the fuse block
provides circuit protection for the components in this 12
VDC system. Ground wires used for 12 VDC circuits
have black insulation.
An on--board, fully automatic, high efficiency 1kW smart
charger with 85 -- 265 VAC global input is attached to the
vehicle for charging the battery pack. The vehicle con-
troller prevents the vehicle from operating while charg-
ing the batteries. Charger activity can be monitored at
the indicator LED near the battery charge receptacle on
the left side of the vehicle.
Testing and service information about components used
in the Workman GTX electrical system is included in the
Component Testing and Service and Repairs sections
of this chapter.
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Workman GTX Electric