Siemens S7-300 - Page 18

18
Product Information on the Manual S7-300 Module Specifications, Edition 11/2002
A5E00213444-02
Prerequisites
S The DP master and DP slave must support clock synchronization. STEP 7 as of
Version 5.2 is required.
Mode: clock synchronization
The following conditions apply to clocked mode:
Filter and processing time T
WE
between the actual values being read in
and made available in the transfer buffer
(the specified value for T
WE
applies regardless of the activation of the
hardware interrupt or diagnosis)
516 to 606 ms
Includes an input delay of 80 ms
T
DPmin
3.5 ms
Diagnostic interrupt max. 4 x T
DP
Note
In clocked mode, the integration time for the module is always set to “none” or
“interference frequency”, regardless of the parameter assignment in STEP 7.
Hardware interrupt functionality is not possible in clocked mode.
Calculation of the filter and processing time
The same time conditions apply regardless of the number of channels
parameterized. The point of time in relation to the clock signal at which a specific
channel is read in is calculated on the basis of the following formula:
T
WE
_CH = (channel number +1) x 52 ms + tv; tv = 100 to 190 ms
CH7 CH6 CH5 CH4 CH3 CH2 CH1 CH0
52ms52ms52ms52 ms52ms52ms52ms52ms 100ms ... 190ms
A/D conversion
Internal processing (tv)
T
WE
T
i
Figure 6 Figure 7 Calculation of the filter and processing time