Processing The Special Function - Siemens SIMATIC S5 Manual

Channel 14
The same conditions apply to channel 14 as to channel 13. The actual value is calculated as follows:
The conversion value is entered in message 15, bytes 4 and 5.
The actual value is output in message 17, bytes 28 and 29 in the units of the conversion value.

3.4.5 Processing the Special Function

Reading in measured values (channel 13)
By setting main control byte 4, bit 0 "start reading pressure curve", 60 actual values are read into
an internal table at equidistant instants via channel 13.
The start bit resets the acknowledgement bit "reading measured values complete" in status byte
1, bit 2 (the start bit is also reset by the IP).
After reading in the 60 values, the acknowledgement bit is set to 1. After this, the 60 values can
be read out in messages 22 to 25.
The total time of the reading in function is set by message 15, byte 6 (duration of acquisition) (max.
255 seconds, min. 6.6 seconds).
The duration of acquisition is rounded up or down to multiples of 3 or 6 seconds.
(Values 8s are rounded down to 6s, values
values 14s are rounded down to 12s, values
or values 4s are rounded down to 3s, values
If only 30 values are input, the values 31 to 60 are not defined.
In addition to this, the module records the maximum value which occurred on channel 13 during
this time. The maximum value is entered in message 20, bytes 26/27 and compared with the
setpoint of message 13, bytes 0/1 and its tolerances in bytes 2 and 3. If the tolerance is exceeded,
the appropriate error bits are set.
Note:
If the module recognizes the signal "read measured value at channel 14 once" during the measured
value acquisition on channel 13, a measured value is assigned the value 0 if the acquisition times
are 8 s.
IP244
C79000–B8576–C860–02
Special Functions for Plastic Machines
9s are rounded up to 12s
15s are rounded up to 18s
5s are rounded up to 6s.)
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