Siemens SIMATIC S7-300 CPU Data: CPU 315-T-2 DP User Manual

Cycle and response times
7.3 Response time
7.3.3 Longest response time
Conditions for the longest response time
The following figure shows you how the longest response time results.
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Figure 7-7 Longest response time
Calculation
The (longest) response time is made up as follows:
• 2 x process image transfer time for the inputs +
• 2 x process image transfer time for the outputs +
• 2 x program processing time +
• 2 x operating system processing time at the SCC +
• 4 x runtime of the DP slave frame (including processing in the DP master) +
• Delay in the inputs and outputs
This is equivalent to the sum of twice the cycle time and the delay in the inputs and outputs
plus four times the DP cycle time.
S7-300 CPU Data: CPU 315T-2 DP
Manual, 12/2005, A5E00427933-02
7-13

Siemens SIMATIC S7-300 CPU Data: CPU 315-T-2 DP Specifications

General

Programming Language	STEP 7
Power Supply	24 V DC
Number of DP masters	1
Processable Technology objects	Yes
Number of counters	256
Number of timers	256
S7 communication	Yes
Number of connections for S7 communication, max.	16
PG/OP communication	Yes
Global data communication	Yes
Integrated DP interface	Yes
Integrated PROFINET interface	No
SIMATIC Computing Platform	No
Operating Temperature	0 to 60 °C
Integrated Interfaces	MPI, DP
Communication	PROFIBUS DP
Cycle Time	0.1 ms
Engineering with	STEP 7
Backup available	Yes
Transmission rate, max.	12 Mbit/s