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Trigger
4-8
MS-710 Scanner User’s Manual
4–Read C
y
cle
External Trigger Edge
Important: Level and Edge apply to the active logic state (Active Open or Active
Closed) that exists while the object is in a read cycle, between the rising edge and fall-
ing edge. Rising edge is the trigger signal associated with the appearance of an object.
Falling edge is the trigger signal associated with the subsequent disappearance of the
object.
Usage: This mode is highly recommended in any application where conveying
speed is constant or if spacing, object size, or timeouts are consistent.
Definition: External Trigger Edge, as with Level, allows the read cycle (active
state) to begin when a trigger (change of state) from an external sensing
device is received. However, the passing of an object out of sensor range
does not end the read cycle. The read cycle ends with a good read output
or, depending on
End of Read Cycle setting, a timeout or new trigger
occurs.
Serial Cmd: < Kg3 >
Figure 4-2 Trigger Edge
Initiate Read Cycle:
Object # 1, moving in front of the detector
beam, causes a change in the trigger state,
initiating the read cycle.
Initiate Second Read Cycle:
Object # 2, moving in front of the detector
beam, causes another change in the trigger
state. This signal initiates a new read cycle
and ends the previous read cycle unless
Timeout is enabled and a good read or tim-
eout has not occurred.
Associated waveforms assume
External Trigger State is set
to Active Closed.