Siemens SIMATIC PCS 7 Operating Manual page 145

T parameter
DPPA_L_DLY
● Additional delay time with a DP/PA coupler in a singular system
● Or additional delay time and switchover time due to a DP/PA link in the redundant system
Precondition
Switchover time with unchanged PA configuration
Switchover time when configuration is changed during oper-
ation
* With unchanged PA field device addresses
T parameter
Slave
Maximum delay time with the IM:
● ET 200M
A typical value is 1 ms for the ET 200M with IM 153
● ET 200iSP
The delay time must be calculated for the ET 200iSP. The following equation enables an
approximate calculation of the ET 200iSP response time with the IM 152: Response time
[ms] = g + 0.065 ms x b
Explanation of the parameters:
– g: Base value of the IM 152 depending on the operating mode
– b: Sum of all input and output bytes of the electronic modules
The following assignment applies to the base value of the IM 152:
Operating mode
No redundancy mode IM 152
Redundancy mode IM 152
* The specified base values are valid only for cyclic data exchange. Acyclic activities (for example, diagnostic interrupts)
are not considered.
Compendium Part B - Process Safety (V8.2)
Operating Manual, 07/2016, A5E35031794-AB
Switchover time
Typ.: 70 ms + number of PA field devices x 51 ms
Max.: 820 ms + number of PA field devices x 50 ms
Typ.: 80 ms + number of PA field devices* x 67 ms
Max.: 800 ms + number of PA field devices* x 130 ms
Base value (g)*
1.5 ms
2 ms
Configuring the safety program
7.11 Monitoring times and system response times
145