JLG TF6-42 Service Manual - Manuale (Pagina 197)

8
2. Safety Related Aspects
2.1 Considered Faults
· Over voltage
· Under voltage
· Internal faults
· Program out of control
· Intermittent power loss
· Incorrect input patterns
· Faults on speed sensors
· Faults on Analog sensors
· Faults on outputs
2.2 Behaviour in Case of Faults
2.2.1 General
The APC160 has been designed to guarantee automatic selection of Neutral in some conditions. This
is accomplished through use of two separate watchdog timers and hard-wired SHUTDOWN circuitry in
the controller's output circuitry.
The response to faults highly depends on the operating mode at the time the fault occurs. In the
description of responses, the following terms are used to relate to each mode:
Platform Control Mode: Operation from the platform
Cabin Control Mode: Refers to driving from the cabin with the platform attached – 2
submodes exist:
Cabin-AWP: Operation from the cabin with speed control while the platform
is attached
Cabin-Handler: Operation from the cabin with manual throttle and brake control
while the platform is attached
Handler: Operation from the cabin without platform attached
2.2.2 Reset Condition
When power is applied, the APC160 first selects Neutral with 3 rd range clutch engaged and starts
initialising itself. This includes a series of self-tests to assure system integrity.
This position is believed to be the safest possible condition in case of an intermittent power failure.
The initialisation phase takes about 1 second. It includes Power On Self Test and integrity testing of
the redundant SHUTDOWN path.
After power up, the APC160 is in the so-called Neutral Lock State. This means that the parking brake
is ON and the transmission remains in Neutral until the shift lever is cycled physically through Neutral
(after turning off the parking brake).