Pilz PSS SB HYD, Basic license - Manual (Page 246)

8-10
Examples
Modular Block System: Hydraulic Presses
Feedback loop monitoring (selective shutdown), category 4
Block used: SB067/RFK_K4
WARNING!
If only one contactor is used to switch a potentially dangerous drive, it
must be possible to switch this contactor off via a group contactor situated
within the current path. This group contactor must be controlled with the
AND-linked FG-signals of the individual main contactors and must be
monitored with a feedback loop.
The subordinate main contactors may only switch on if the group contactor
monitor
FG = 1. The switch-on signal from the subordinate contactors
must form an AND-connection with the FG-signal from the group contactor
and must be assigned to the
Ein-parameter of the main contactor monitor.
If only one feedback loop is used, the feedback input will be connected to
RFK1 and RFK2.
Please note:
The feedback loops must be wired inside the control cabinet. If this is not
possible, the feedback loops must be pulsed.
Fig. 8-9: Wiring diagram
L1 24 V
N
M1.1
K-M1.1
K-G1
RFK
K-M1.1
E0.0 E0.1
PSS
+ A1.16 -
K-M1.1 K-M1.2
M1.2
K-M1.2 E0.8
RFK
K-G1
M1.1
START
RFK
K-M1.2
E0.2 E0.9
M1.2
START
K-G1
0 V
M M
+ A1.17 - + A1.18 -