3
07.96
Description
3-21
Siemens AG 1996 All Rights Reserved 6ZB5 430–0BH02–1AA0
SINUMERIK 805SM / 840C (BS)
Note
For detailed information on the diagnostics possibilities in the STEP 5
program of the master, please refer to
Reference:
/1/, SIMATIC S5 Distributed I/O System ET 200
PLC STOP in the slave station
If it is found from the diagnostics that the station to be ckecked has an error
and can be contacted, the device-related diagnostics (station diagnostics) can
be used to detect the cyclic operation of the slave control:
Call station diagnostics from the SINEC L2-DP slave interface module.
Enter station number (here: 5; can be between 3 and 124) in the “diagnostics
address” byte. The byte “diagnostics a 1” always has the value 3.
Read station diagnostics from the SINEC L2-DP slave interface module.
Load diagnostics word.
Is bit 0 of the “diagnostics a 1” byte
set?
If so,
then
no cyclic operation of the slave control (evaluate in FBy
correspondingly).
Reset of the inputs implemented by the slave in the master station.
A self-defined sign-of-life bit can enable the user to detect a fault in cyclic
operation of the slave station on the master side.
An output bit of the slave to be monitored is set on the slave side and on the
master side the signal state of the corresponding signal bit is read and
evaluated as follows:
1 signal:
Cyclic operation of slave control running
0 signal:
Fault during cyclic operation of slave control
Based on the signal state of this input bit, the user can have a suitable error
message displayed and can program the behaviour of the control should this
fault occur.
Example
.
.
.
L KY 5,3
T PW 252
L PW 252
L KH 0001
UW
L KH 0000
> <
F
SPB FBy
.
.
.
Consequences of
a fault
Monitoring of
cyclic operation of
the slave station
by the user
Example
3.2 Description of the DP standard slaves
