Table 16-5 Portion Of The Process Image Transfer Time, Cpu 417-4H - Siemens SIMATIC S7-400H System Manual

S7-400 cycle and reaction times
16.2 Calculating the cycle time
Table 16-5 Portion of the process image transfer time, CPU 417-4H
Allocation
n = number in bytes in the process image
m = number of accesses to process image
K Base load
A In central unit
**)
Read/write byte/word/double word
B In expansion unit with local link
**)
Read/write byte/word/double word
C In expansion unit with remote link
**)***)
Read/write byte/word/double word
D In the DP area for the integrated DP interface
Read byte/word/double word
D In the DP area for the external DP interface
Read/write byte/word/double word
E1 Consistent data in the process image for the integrated DP
interface
Read/write data
E2 Consistent data in the process image for the external DP
interface (CP 443–5 extended)
read/write data
The module data is updated with the minimum number of accesses.
*)
(e.g.: 8 bytes result in 2 double word accesses, and 16 bytes in 4 double word accesses.)
In the case of I/O inserted into the central unit or into an expansion unit,
**)
the specified value contains the execution time of the I/O module
Measured with IM460-3 and IM461-3 at a link length of 100 m
***)
Extension of the cycle time
The calculated cycle time of a S7-400H CPU must be multiplied by a CPU-specific factor.
The table below lists these factors:
Table 16-6 Extension of the cycle time
Startup 412-3H
stand-alone mode
Factor 1.04
Long synchronization cables may further increase cycle times. by up to 10 % per cable
kilometer.
264
*)
412-3H 414-4H
redundant stand-alone mode
1.2 1.05
CPU 417–4H
stand-alone mode
3 µs
m * 7.3 µs
m * 20 µs
m * 45 µs
m * 1.2 µs
m * 5 µs
n * 0.25 µs
n * 2.25 µs
414-4H 417-4H
redundant mode stand-alone mode
1.2 1.05
System Manual, 09/2007, A5E00267695-03
CPU 417–4H
redundant mode
4 µs
m * 15.7 µs
m * 26 µs
m * 50 µs
m * 13 µs
m * 15 µs
n * 2.5 µs
n * 3.4 µs
417-4H
redundant mode
1.2
S7-400H