X20(c)SC2212
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Data sheet V1.141 X20(c)SC2212 Translation of the original documentation
17.2 Data transmission time on the bus
The following relationship must be taken into consideration for the data transmission time on the bus:
•
The time needed to transfer data from the input to the SafeLOGIC controller or to the output depends on
the sum of the cycle times and CPU copy times in effect on the transfer line.
•
POWERLINK MN (managing node, standard CPU) settings are important for the actual timing on the bus,
but they cannot be used from a safety point of view since the values can be changed at any time in the
course of modifications made outside of the safety application.
•
In the SafeLOGIC controller, data transmission times are monitored on the bus using openSAFETY ser-
vices. The time needed to process the application on the SafeLOGIC controller is taken into account in
this test (system-dependent). Monitoring is defined in SafeDESIGNER using the parameters in parameter
group "Safety Response Time".
Information:
The safety components located in this network segment could be cut off by the SafeLOGIC controller if
modified parameters on the POWERLINK MN alter the data transmission times on the bus so that they
lie outside of the SafeDESIGNER parameters defined in parameter group "Safety Response Time".
Information:
The safety components located in this network segment could be cut off by the SafeLOGIC controller
if EMC disturbances cause data failures that fall outside of the SafeDESIGNER parameters defined in
parameter group "Safety Response Time".
Calculating the maximum data transmission time - up to Release 1.9:
•
The total max. data transmission time on the bus is calculated by adding pa-
rameter "Worst_Case_Response_Time_us" for the safe input module and parameter
"Worst_Case_Response_Time_us" for the safe output module. When doing this, be sure to check para-
meter "Manual_Configuration". If parameter "Manual_Configuration" is set to "No", the value specified for
parameter "Default_Worst_Case_Response_Time_us" is used.
•
Special case: Local inputs on the X20SLX module:
The total max. data transmission time on the bus is calculated by adding parameter "Cycle_Time_max_us"
+ 2000 µs and parameter "Worst_Case_Response_Time_us" for the safe output module. When doing this,
be sure to check parameter "Manual_Configuration". If parameter "Manual_Configuration" is set to "No",
the value specified for parameter "Default_Worst_Case_Response_Time_us" is used.