Efficient Networks Siemens Sinamics S120 User Manual

Page of 560
Communication PROFIBUS DP/PROFINET IO 
 
10.3 Communications via PROFINET IO 
 
Drive Functions 
450
 
Function Manual, (FH1), 07/2007 Edition, 6SL3097-2AB00-0BP4 
Setting criteria for times 
●  Cycle (T
DC
–  T
DC
 must be set to the same value for all bus nodes. T
DC
 is a multiple of SendClock. 
–  T
DC
 > T
CA_Valid
 and T
DC
 ≧ T
IO_Output
 
T
DC
 is thus large enough to enable communication with all bus nodes. 
 
NOTICE 
 
 
After T
DC
 has been changed on the PROFINET IO controller, the drive system must 
be switched on (POWER ON) or the parameter p0972=1 (Reset drive unit) must be 
set. 
●  T
IO_Input 
and T
IO_Output
 
–  Setting the times in T
IO_Input
 and T
IO_Output
 to be as short as possible reduces the dead 
time in the position control loop. 
–  T
IO_Output
 > T
CA_Valid
 + T
IO_Output_MIN
 
●  Settings and optimization can be done via a tool (e.g. HW Config in SIMATIC S7). 
User data integrity 
User data integrity is verified in both transfer directions (IO controller <––> IO device) by a 
sign of life (4-bit counter).  
The sign-of-life counters are incremented from 1 to 15 and then start again at 1. 
●  IO controller sign of life 
–  STW2.12 ... STW2.15 are used for the IO controller sign of life. 
–  The IO controller sign-of-life counter is incremented on each IO controller application 
cycle (T
CACF
). 
–  The number of sign-of-life errors tolerated can be set via p0925. 
–  p0925 = 65535 deactivates sign-of-life monitoring on the IO device. 
–  Monitoring 
The IO controller sign-of-life is monitored on the IO device and any sign-of-life errors 
are evaluated accordingly. 
The maximum number of tolerated IO controller sign-of-life errors with no history can 
be set via p0925. 
If the number of tolerated sign-of-life errors set in p0925 is exceeded, the response is 
as follows: 
1. A corresponding message is output. 
2. The value zero is output as the IO device sign of life. 
3. A new synchronization with the IO controller sign of life is started. 
●  IO device sign of life 
–  STW2.12 ... STW2.15 are used as IO device sign of life. 
–  The IO device sign-of-life counter is incremented in each DC cycle (T
DC
).