Omron CRT1 - 10-2009, Operation Manual

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500
Functions of Digital I/O Slave Units
Section 11-3
• Measurement time: 0 to 4,294,967,295 s
(Stored data: 0000 0000 to FFFF FFFF hex)
• Measurement unit: s
Note (1) The total ON time monitor and the contact operation monitor cannot be
used for the same contact at the same time. Select only one of these
functions under the
Detection Mode .
(2) This function does not operate if the I/O power is not turned ON.
(3) The Total ON Time Monitor Function checks at 1 second intervals wheth-
er or not the connected device is turned ON. Keep this in mind when mea-
suring total ON times for inputs of less than 1 s.
■ Measuring an ON Time of 0.5 s
As shown in Figure A , the actual ON time is 1.5 s (3
×
0.5 s) but the total ON
time is measured only as 1 s because the input is ON only once when a mea-
surement is taken.
In Figure B , the actual ON time is 1.5 s (3
×
0.5 s) but the total ON time is
measured as 2 s because the input is ON twice when a measurement is
taken.
■
Measuring an ON Time of 1.5 s
In Figure C , the actual ON time is 3 s (2
×
1.5 s) but the total ON time is mea-
sured as 4 s because the input is ON 4 times when a measurement is taken.
ON
OFF
Stored in Slave
Unit memory
Slave Unit
I/O power supply
Total ON time
Connected device
Sensor
Total ON time
Measured approx. every 1 s
Figure A
0.5 s
ON
OFF
0.5 s
ON
OFF
Figure B
Measured approx. every 1 s