Safety Integrated - Industry - Siemens

Settings of the failsafe F-DO
The settings are displayed after double-clicking "4 F-DO
DC24V/2A" (see "Overview picture").
DIL switch settings
This value has to be set on the module (F-DO).
F monitoring time
It has to be observed that the F monitoring time must be
larger than the call time of OB 35.
Channels which are not used (channel 2 and 3): Deactivate
Channel 0: For switching the contactors K1 and K2 (group 1
with motor M1).
Channel 1: For switching the contactors K3 and K4 (group 2
with motor M2).
The read-back time defines the duration of the switch-off procedure
for the respective channel. If the respective channel
switches high capacity loads, the read back time should be set
sufficiently large. We recommend setting the read back time
as small as possible, however large enough so that the output
channel does not become passive.
Basic Performance Data
Load and main memory (without program code)
Load memory approx.
37,5 k
Main memory approx.
28,2 k
Load and main memory (with program code)
Cycle time
Total S7 standard
blocks
F blocks (failsafe)
approx. 0,2 k approx. 37,3 k
approx. 0,09 k approx. 28,1 k
Total S7 standard
blocks
F blocks (failsafe)
Load memory approx.
47,7 k
approx. 1,0 k approx. 46,7
Main memory approx.
34,7
approx. 0,4 k approx. 34,2
Total cycle time
(typical value)
Max. runtime of the
safety program
approx. Standard and safety program
5 ms
8 ms Calculation with the Cotia table.
Page 277 specifies where
to find it.
Functional Example No. AS-FE-I-009-V10-EN 287
Ex. No.
9