Festo Контроллер двигателя CMMD-AS - Manual (Page 85)

4. Functional safety engineering
Festo P.BE-CMMD-AS-HW-EN 1002NH 85
Explanations of the switching example
The switching example shows a combination of the CMMS-AD with two PILZ PNOZ X2P
safety switch devices. An emergency stop in combination with a protective door is used as
a switch device. In total, three logic elements can be switched in series. A door position
switch can also be used that keeps the protective door closed until the drive has stopped
or the "Driver supply acknowledgment" signal indicates a safe state and the plausibility
check is successful.
Technical data, such as max. current, etc. can be found in the data sheet of the safety
switchgear.
4.2.4 EMERGENCY STOP request, monitoring of protective door
After an Emergency Stop button is actuated or a protective door is opened, the two
normally open contacts K1 or K2 (13, 14 and 23, 24) open immediately. This results in the
immediate removal of the output stage enable and disconnection of the driver supply via
[X3] pin 2. The unintended opening of the protective door must be prevented in the
system.
Approx. 80 ms after opening of the PNOZ contacts for switching off the driver supply, the
acknowledgment contact ([X3.1] or [X3.2], pin 5 and 6) is closed (t11 – t12, chapter 4.2.2
"Timing diagram, STO").
At time t13, an "H" is displayed on the 7-segment display of the servo controller to
indicate a "Safe halt". This occurs at least 30 ms after the the potential-free
acknowledgment contact closes (t13-t12).
Due to the drawn circuitry, a two-channel operation with cross-circuiting recognition is
possible. This permits recognition of:
- Earth faults in the start and initial circuit
- Short circuits in the start and initial circuit
- Cross circuits in the initial circuit.
Removal of the output stage enable and switching off the driver supply via [X3.1] or [X3.2]
pin 2 causes the drive to run out.