Siemens SINAMICS S120 Function Manual page 244

Control of the safety functions
5.6 Control of the Extended/Advanced Functions via F-DI (for CU310-2)
The monitoring time (p10002) for the discrepancy of the two digital inputs of an F-DI may
have to be increased so that switching operations do not trigger an undesired response,
thereby necessitating a safe acknowledgment. The signal states at the two related digital
inputs (F-DI) will need to have the same state within this monitoring time or fault
C01770/C30770 will be triggered, "discrepancy error" (CU310-2). This requires safe
acknowledgment.
Note
Discrepancy time
The discrepancy time must be set so that it is always less than the smallest expected
switching interval of the signal at this F-DI (see also the following diagram "Discrepancy
time").
Further notes for setting the discrepancy time are contained in the "SINAMICS S120/S150
List Manual" for the following messages:
• F01611 (Basic Functions)
• C01770 (Extended/Advanced Functions)
T
S
T
D
T
R
Figure 5-7
242
Switching interval
Discrepancy time
Response time
Discrepancy time
Function Manual, 12/2018, 6SL3097-5AR00-0BP1
Safety Integrated