Siemens SINUMERIK 840Di Manual page 242

7 PROFIBUS DP Communication
7.3 SIMATIC S7 project
Dialog:
cont'd.
Actual-value
sensing
T
I
Dialog:
cont'd.
Setpoint
acceptance
T
O
Dialog:
cont'd.
7-242
Notice
On a DP slave 611U used with SINUMERIK 840Di, the ratio between the mas-
ter application cycle T
MAC
Master application cycle = DP cycle
Tab: Clock synchronization
Master application cycle [msec]:
Factor: 1
The parameter: Actual-value sensing Ti defines the time at which the actual
value (actual position value) can be read in from a DP slave 611U.
It is recommended to use the same value for the time of actual-value sensing Ti
for all DP slaves 611U, in particular, if the axes interpolate.
Notice
The following condition must be observed for the time of actual-value
sensing T :
I
DP cycle >= actual value acquisition >= basic time
Tab: Clock synchronization
Actual-value sensing [msec]:
Factor: Factor
The parameter: Setpoint Acceptance To defines the time when the speed set-
point of the NC position controller is accepted by a DP slave 611U.
It is recommended to use the same value for the time of setpoint acceptance To
for all DP slaves 611U, in particular, if the axes interpolate.
Notice
The following condition must be observed for the time of setpoint
acceptance T :
O
DP cycle >= setpoint acceptance >= equidistant master cycl. portion +
Tab: Clock synchronization
Setpoint acceptance [msec]:
Factor: Factor
and DP cycle time T must be 1:1.
DP
basic time
 Siemens AG, 2003. All rights reserved
SINUMERIK 840Di Manual (HBI) – 06.03 Edition
06.03