Model 9600/9700 Swing-Reach ® Lift Truck
Section 8. Theory of Operation System Architecture
Communications Overview Vehicle operation is accomplished via several input and feedback mechanisms. The system has two separate communication (BUS) lines which distribute appropriate information to multiple devices. See Figure 8-1 on page 8-2. NOTE: The Tractor Manager is the main controller in the system. All communication is routed through the Tractor Manager. •
BUS0 provides communication between the Traction Power Amplifier, Lift Power Amplifier, Guidance Manager, and Tractor Manager.
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BUS1 provides communication between the Tractor Manager, Carriage Manager, and Display Interface Card.
NOTE: The Display Interface Card controls the Operator Display.
Tractor Manager The Tractor Manager (TM) is the main controller in the system. It communicates with all other devices that are on the communication lines, BUS0 and BUS1. The TM receives information on the status of multiple devices such as the Deadman pedals, Mini Height Prox, Load Handler position and right hand Control Handle from the Carriage Manager. It also receives Traction Motor speed, direction, and temperature information from the Traction Power Amplifier (TPA) and Lift Motor speed, direction, and temperature information from the Lift Power Amplifier (LPA). The TM determines allowable vehicle operation based on those inputs and operator requests. The TM directly monitors and controls the steering system of the truck in both Auto and Manual modes of operation. The TM calculates and maintains the fork height count based on direct inputs from the Lift Reference Proximity switch, Height Encoder and Mini Height Prox. The TM will impose a deceleration of the lift/lower system as it approaches full elevation and also a reduction in lowering speed when approaching the bottom. The TM calculates load weight based on main and mini lift system pressures. The TM reduces travel speed as
Publication: 1089040, Issued: 08 Apr 2016
necessary, based on platform height, load weight, load handler position, and optional devices. When in the guided mode, the TM receives information regarding truck position relative to the guide wire from the Guidance Manager (GM). During guided operation, the TM receives steer correction requests from the GM. It is the TM that slows or stops the truck as Heading Angle (HA) and Distance From Wire (DFW) limits are reached or exceeded. The TM calculates the Battery State-of-Charge (BSOC) from the voltage measured at Battery Sense In. The TM controls the relay enable circuit that, when the circuit is completed, activates the relays on the Fuse/Relay Card, and provides B+ to all solenoid and contactor coils. The TM also controls the Operator Display and is the only manager that can display fault codes. A copy of the vehicle identity is stored in the TM.
Carriage Manager The Carriage Manager (CM) is an input device for deadman switches, sidegate switches, mini height prox, steering encoder, travel pot, lift pot, and optional devices. It communicates with the TM via BUS1. The CM controls operation of the traverse/reach and rotate functions. It also calculates Load Handler position. A copy of the vehicle identity is stored in the CM.
Traction Power Amplifier The Traction Power Amplifier (TPA) communicates with the TM only via BUS0. It receives all commands regarding travel direction and speed. The TPA monitors both the Traction Motor Encoder (TME) and Traction Motor Temperature (TMT) sensor. It determines, based on encoder feedback and the travel request, how it should control the motor, and determines if the performance has satisfied the travel command from the TM. If it has not, the TPA adjusts the motor control voltage or sends a fault code to the TM, as appropriate. The TPA is solely responsible for controlling Traction Motor current. The TPA sends the Traction Motor temperature to the TM. The TM then alters the travel request if necessary, depending on Traction Motor temperature. The TPA monitors its internal temperature and limits current or travel speed as required by its
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