Siemens SINUMERIK 840C Installation Instructions Manual page 602

8 PLC Machine Data (PLC MD)
8.2 PLC MD for the operating system (system data)
124
125
126
127
Default value
- 1
This PLC MD can be used to define as many as 4 input bytes as alarm bytes. The PLC
software scans these bytes for changes every 10 ms. Enter - 1 for input bytes that are not to
serve as alarm bytes.
The PLC outputs an error message and goes to STOP if illegal values are detected on a cold
restart.
If enabled in PLC MD 6050, bit 3 (bit 3 = 0), OB 3 is invoked when an alarm is generated.
128
Default value
64
129
Default value
72
These PLC MD specify the start address (byte) for the machine control panels.
Eight bytes are required for each control panel. The inputs and outputs for each control panel
have the same address numbers.
8–10
Byte no. of 1st alarm byte
Byte no. of 2nd alarm byte
Byte no. of 3rd alarm byte
Byte no. of 4th alarm byte
Lower input limit Upper input limit
127 (SW 4 and
- 1
Address 1st machine control panel
Lower input limit Upper input limit
127 (SW 4 and
0
Address 2nd machine control panel
Lower input limit Upper input limit
127 (SW 4 and
0
© Siemens AG 1992 All Rights Reserved
Units
higher)
Units
higher)
Units
higher)
6FC5197- AA50
SINUMERIK 840C (IA)
09.95
DB 60
DW 124
DB 60
DW 125
DB 60
DW 126
DB 60
DW 127
–
DB 60
DW 128
–
DB 60
DW 129
–