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AF9ZP0BA - EPS-ACW REACH TRUCK - User Manual
before SW2 toggles. This is a safety relevant issue and should be avoided.
To do that it is possible to involve the 90 degrees switch (SW2) to limit the
angle (i.e. the angle will be limited when two conditions occur):
a) encoder counting overtakes the max angle setting
AND
b) the 90 degrees switch (SW2) toggles
To enable this handling, turn option SW2 LIMITING to ON.
16.2 Safety Function to stop the Traction following an epsacW alarm
U
In case of an alarm in the steering system, the job in the Zapi steering
assembly finishes when the STOP TRACTION REQUEST info (Bit in a PDO)
and the alarm code (EMERGENCY or PDO frame) has been released on the
CAN BUS (ask the object dictionary to the Zapi technicians).The procedure
to turn the traction to a safe state when the steering system reports an
alarm is FULLY UNDER THE RESPONSABILITY OF THE LIFT TRUCK
MANUFACTURER and so he has to take care this procedure will be 100%
effective. Furthermore, special cares are recommended in case the module
designated to lead the traction to a safe state (Traction Control Module =
TMC) IS NOT A ZAPI’s UNIT (ask to Zapi technicians for properly
coordinating the communication between EpsacW and TMC).
16.3 Vehicle Master Control (VMC) Safety Functions
U
Together with the safety function to stop the traction (see topic 16.2) the
VMC in general has a second Safety Relevant function: it sends a PDO to
the EpsacW to turn the steering control from rest to Operational. Typical
situation is:
1) A main contactor, driven by the VMC or by another unit in the truck,
supplies the Battery Power to the EpsacW.
2)The EpsacW is expected to stay at rest until the main contactor will be
closed (to avoid unwilling alarms).
3) VMC will communicate on a PDO (VMC -> EpsacW) when the main
contactor has been closed and the EpsacW turns Operational.
This function is Safety Relevant because, the event with the VMC
commands the traction moving and forgets to command the steering to
Operational leads to an unsafe situation (traction moving and no steer).
This is a single fault leading to a lost of safety. So, for fulfilling with
ISO13849, this Safety Function of the VMC should be designed according
the PLd and Category #3 requirements.
A good practice to avoid this constrain could be:
1) Do not connect the EpsacW under the main contactor driven by the VMC
