Siemens SIMATIC S7 - 3.2 Digital Outputs and Comparator Channel

4-6
SM 338 Equipment Manual
(4) J31069-D401-U1-A0-7618
The assigned counters for each sensor are set in one byte.
Table 4-3 shows the respective byte assigned.
Table 4-3 Bytes for setting the counters
Sensor Number
Byte
1 4
2 7
3 10
4 13
Measuring cycle time
00000 16.0msec
00001 0.5msec
00010 1.0msec
..
..
..
11111 15.5msec
Starting the counter
0: Immediately with sent START pulse
1: With echo of the sent START pulse
Selecting the edge
Counter starts/stops with
0: Rising edge (L ® H)
1: Falling edge H ® L)
Resolution
0: 0.10 mm (max. meas. range of
approx. 6 m)
1: 0.05 mm (max. meas. range of
approx. 3 m)
70
Byte (n+2)
Measuring cycle time
The measuring cycle time can be set in increments of 0.5 msec depending on
the sensor being used (length and required dead times). The maximum mea-
suring cycle time is 16 msec.
Starting the counter
When the counter is started with the sent START pulse, the maximum mea-
suring distance is reduced by the signal run time (approaching and returning
line) through all components. If the counter is started with the echo of the
START pulse, a synchronization error occurs.
Selecting the edge
Set the edge as described by the manufacturer of the sensor.
Sensor-related
counter setting
D
a
t
a
Communic
a
tion with the PLC