Function Of Safe Direction (Sdi); Configuring Sdi - Siemens Simatic ET 200SP Equipment Manual

4.9.3.1

Function of Safe Direction (SDI)

The SDI function monitors the encoder and
notifies the user if the encoder/count moves
more than a defined amount in the unin-
tended direction.
Examples of how the function can be used
Example
A protective door can only be opened if a conveyor
belt moves in the safe direction (away from the
operator).
When replacing the pressure cylinders of the plates,
the conveyor can only move in the safe direction.
Once the protection against jamming has been
triggered, a roller shutter gate can only start mov-
ing in one direction.
At an operational limit switch, the trolley of a crane
can only start moving in the opposite direction.
4.9.3.2

Configuring SDI

In STEP 7 do the following to configure SDI:
• Configure "Safety Function - Safe Direction"
• Configure the "Monitoring tolerance"
• Download this project to the F-CPU
ET 200SP F-TM Count 1x1Vpp sin/cos HF (6ES7136-6CB00-0CA0)
Equipment Manual, V1.0, 01/2021, A5E47073911-AA
Parameters/address space
Possible solution
• Specify the safe direction using the "Safe
Direction" control bit in your safety program
in the F-CPU.
• Enable SDI in the counter via your safety
program in the F-CPU.
• Enable the locking mechanism of the pro-
tective doors via the PROFIsafe status bit of
the counter.
• Specify the safe direction using the "Safe
Direction" control bit in your safety program
in the F-CPU.
• Enable SDI in the counter via your safety
program in the F-CPU.
• Inhibit the direction of motion that is not
permitted in the counter.
4.9 Safety functions
59