Systems Overview Toyota Pallet Truck Service Manual Theory of Operation Theory of Operation Monitors the travel circuits for fault conditions and responds appropriately Vehicle Manager (VM) Traction System The programmable motor control functions are performed by the electronic circuitry housed within the control handle vehicle manager (VM). The basic functions of the VM include: Battery Plugged In When a fully-charged battery is plugged in, the truck has B+ and B- supplied to the following points:
Monitoring relative positioning of the directional/speed control to eighteen hall effect sensors for speed and direction control B+ to and thru FU1 to the normally-open M2 contactor Monitoring the position of the emergency reverse button for emergency reversing of the truck direction B+ to and thru FU3 and to the open SW1 B+ to and thru FU2 to the normally-open M1 contactor Monitoring truck performance and providing input data and commands to the operator display B- to the B- lug on the TPA, JP3-4 on the VM, and J5-2 on the service port interface Providing lift/lower input commands to the traction power amplifier (TA) Key Switch ON and M1Energized When the key switch is turned ON, the control handle must be in the correct position to close the brake (deadman) switch (SW2).
See “Brake (Deadman) Switch” on page 5-11. B+, B-, 5V, and 12V are supplied to the following points: Monitoring Jog Pick logic and speed control engage commands Monitoring jog switches S112 and S115 for jog control Monitoring horn switches S18A and S18B for horn operation B+ thru SW1 to IGN 1, then to B+ Key on the TPA, JP3-1 on the VM, and J5-1 on the service port interface Monitoring and setting truck performance parameters B+ thru SW18 at JP10-2, thru IGN 2 then thru JP10-1 to JP1-33 (High speed enabled) at the TPA Traction Power Amplifier (TPA) The basic functions of the TPA include:
B+ to the -X side of contactor M1, contactor M2, SOL 1, SOL 2, horn from TPA JP1-13, and grab rail J4-6 Controls the traction motor direction by adjusting the traction motor field polarity according to the directional signal inputs from the VM Contactor M1 is activated thru a ground supplied to the -Y side of M1 thru TPA JP1-6 Controls the traction motor speed and torque by monitoring the position change of the hall effect sensors.
Variable motor speed is determined by voltage, frequency, and phase B+ to the B+ lug on the TPA thru the activated contactor M1 5V is supplied to the Traction Motor Encoder JP6-1 from TPA JP1-26 12V is supplied to SW2, 8, 13, 14, 15, 16A, 16B thru the TPA JP1-25 Controls the emergency reverse circuitry in the VM that provides the directional travel control commands to the TPA and traction motor B- is supplied to TS2 thru TPA JP1-7 3-8 00700-CL398-07, Issued: 9 August 2007