Blue Bird TC/2000, Owner'S Manual

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Start-Up and Emergency Power Battery
The vehicle is provided with a single 12 volt lead acid battery which provides the start-up power for the
vehicle 12 volt power system and emergency power to the bus electronics for emergency flashers and lights
in the event of a drive system failure. The bus electronics will run off this battery when the drive power
system is off or disabled. This battery is located within a compartment under the bus system circuit panel
located outside of the drivers’ window. This battery is provided power to keep it charged from a DC/DC
converter during system operation. In an event of failure to the traction battery system and the DC/DC
converter, this 12 volt battery will provide service to the vehicle electronics. This 12 volt battery closes a relay
between the vehicle 12 volt system and the motor controller 12 volt electronics. The DC/DC converter main-
tains the charge to the 12 volt batteries during motor operation. The system also charges the 12 volt batteries
during traction battery charging. This battery is charged at any time the bus traction system is on or being
charged.
Drive Train Cooling System
The drive train cooling system consists of fans, radiator, battery, pump, motor, and oil which flows through
the system. The oil used in this cooling system is Exxon 2389 and is pumped from the motor, to the radiator
where it is cooled by the fans. After the oil is cooled it flows from the radiator through a filter and then flows
to a motor and speed reducer in parallel. Oil from the speed reducer flows to the motor oil sump where it is
picked up by the oil circulation pump.
MOTOR CONTROLLER
The motor controller is located in the right side rear compartment behind the rear tires. The motor con-
troller contains five (5) printed circuit boards and numerous chassis mounted components. It provides vari-
able voltage, variable frequency, 3-phase AC-output power, forward and reverse phase sequences, and vector
torque control. When powered by a 336 volt DC Traction Battery Pack, the motor controller is capable of
generating up to 640 amperes of AC line current, which will produce 250 foot-pounds of torque at the motor
shaft. It can power the motor up to 230 shaft horsepower. The motor controller weighs approximately 80
pounds and is cooled by Exxon 2389 turbine oil and two (2) fans located in the motor controller cover.
WARNING: The motor controller is a very-high power device, capable of inflicting serious bodily harm
or death through electrical shock. The electronics compartment should only be opened by a qualified
technician.
MOTOR
The motor is a 3-phase, oil cooled, AC induction motor. It is capable of deli/- 250 foot pounds of
torque. The motor is capable of 12,500 RPM in a forward direction (at 55 mph) and 4,500 RPM in reverse (up
to 15 mph). The motor controller limits the reverse speed to a programmable preset limit. Cooled by Exxon
2389 turbine oil, the motor weighs approximately 225 pounds.
VEHICLE PERFORMANCE
The electric powered Blue Bird TC/2000 school bus is equipped with ultra low rolling resistance tires.
With the traction battery pack fully charged, it is capable of approximately an 70 mile range at a constant 45
mile per hour velocity. The vehicle can accelerate from a standing start to 50 miles per hour in approximately
30 seconds. These figures are based on initial testing on level terrain, and subject to operator performance.
Rapid acceleration reduces range capability of the vehicle.