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Rockwell Automation Publication 871FM-UM002A-EN-P - April 2017
Chapter 9
Review the 1734-4IOL IO-Link AOP
Triggered:
This process bit toggles between one or zero depending on the
polarity configuration when the sensor detects the target or not. For normally
open, this bit displays a zero by default when no target is present and a one
when target is present. For normally closed sensors, this bit displays a one by
default and a zero when the target is present.
MarginLowAlarm:
This process bit toggles between one and zero to indicate
if there is enough margin to maintain reliable target detection. This bit is one
when the target is marginal (signal strength is above 0.5X and below 2X). It is
zero when the light levels are above the operating margin if the triggered bit is
active. The following table describes the significance of both bits when
evaluated together:
Proximity:
Displays the status of the proximity alarm. This process data
element is a bit that indicates if there is an object near the threshold (below
1.0X) when the output is OFF.
Gain:
Displays the excess gain above the sensor threshold to maintain reliable
detection of the target.
Signal:
Provides the raw measurement value of the amount of signal reflected
from the target.
Triggered
MarginLowAlarm Description
0
0
No target is present
0
1
No target present, item in background is very close to the sensor threshold
1
0
Target is present and sensor signal is not marginal
1
1
Target is present and signal strength is marginal (0.5x < signal < 2X)