IAI America SCON-C - Manual (Page 158)

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Operation timings
PLC processing 1: [1] The PLC turns OFF the rear end move command signal (ST0) and intermediate point
move command signal (ST2), and turns ON the front end move command signal (ST1).
[2] The PLC sets in the timer the period after a move command is issued until push & hold
operation is completed, to enable monitoring with the timer.
Operation 1: The actuator starts moving and upon reaching the front end (160 mm), it decelerates to the
push speed. The actuator continues to move at this speed until stopping upon contacting
the load.
If the actuator has stopped at a position between 180 mm and 185 mm, the zone output
(PZONE) turns ON.
PLC processing 2: After an elapse of the monitor timer period specifying the time until positioning operation is
completed, the PLC checks the ZONE output (PZONE).
If the zone output signal is ON, indicating that the operation has completed successfully, the
PLC executes sequence processing in the “condition where the load is being pushed.”
Once the sequence processing is completed, the PLC turns OFF the front end move
command signal (ST1) and turns ON the rear end move command signal (ST0).
Operation 2: As soon as the actuator starts moving toward the rear end, the zone signal turns OFF. The
zone signal turns ON again when the actuator reaches the 100-mm position. When the rear
end position is reached thereafter, the rear end position detected signal (LS0) turns ON.
PLC processing 3: If you wish to shorten the tact time by issuing a command to the peripheral equipment while
the actuator is returning to the rear end, the zone output signal can be utilized as a trigger
signal.
* If the front end detected signal (LS1) turns ON but the zone output signal does not turn ON, the actuator
should be deemed to have “missed” the load. If neither the front end detected signal (LS1) nor zone output
signal turns ON, it should be deemed that the “load is set at a wrong position.”