Chapter
11
102
ML-9011A
Chapter
11
Interface Specifications
■
Emergency Stop for Complicated Systems
Interfacing with External Emergency Stop Circuitry
User Supplied Safety Relay Module(s) Required
Complicated Systems are those in which more than one emergency stop sub-circuit must be
linked together. An example of this would be a machine that has a laser marker, parts handler
with pneumatic controls, PLC, and conveyor belt all of which have ESTOP buttons where one
ESTOP button stops all devices. Any situation in which more than one device must be
connected together and respond identically to an emergency stop event is considered a
complicated system.
Complicated systems are integrated using certified safety controllers or safety relays. In this
situation one device is the "master" and the rest of the devices are the "slaves." The laser
marker is considered a slave device in this configuration and its emergency stop must be
controlled by the larger machine's safety controller. The output of the external safety relay
module closes the input to the laser marker and allows the system to clear the emergency stop
state.
In this wiring example a Pilz PNOZ family safety relay module controls the laser marker and
interfaces two external emergency stop buttons. In this example the Pilz device would also
control additional emergency stop functions outside of the laser marker using expansion
contacts. The more devices which must be implemented the more expansion contacts must be
added to the Safety Relay Module. Any suitable IEC13849-1 compliant safety relay controller is
acceptable as long as it is implemented in this manner. The end user is responsible for
verifying compliance of the machine as a whole.
User ESTOP Wiring
ESTOP
Power
A1
A2
Pilz PNOZ s3
Safety Relay
Module
750103
Input
Input
Reset/
Start
S11
S12
S21
S22
S34
Y32
13
23
14
24
K1
K2
Master machine requires
additional outputs if
more slaves are required
ESTOP
Additional ESTOP(s)
ES
T
O
P
ESTOP CH1 rtn
ESTOP CH 1
ESTOP CH 2
Out 1a
Out 1b
Out 2a
Out 2b
Inside
Laser Marker
1
2
3
4
6
7
8
9
14
15
16
17
ESTOP CH2 rtn
Laser Marker Front Panel
ESTOP Button