7.3 Dual-channel Emergency Stop and Cable-pull Switch
Monitoring
Achievable safety rating
Stop category
Features
Safety sensor/operating
mechanism
Notes
Note: All example applications shown are proposals without warranty. In any case the operator has
to perform a safety review of the entire site.
When the emergency stop button is pushed or the cable-pull switch is activated, the EP-19xx
switches off the 24 V supply for the modules (switchable modules refer to the section, General
Contact Information) within the safety segment and thus also contactors K3 and K4. The failure of a
switching element in the emergency stop button or the cable-pull switch as well as a cross-circuit in
their supply lines does not result in the failure of the emergency stop mechanism and is detected
within the fault-reaction time.
The EP-19xx module switches on the 24-V supply for the modules within the safety segment if:
•
Emergency button is unlocked
•
Cable-pull switch is unlocked
•
Feedback circuit (NC contacts of K3 and K4) is closed
•
Start push button has been pushed and released again
Contactors K3 and K4 are controlled by the PLC and can switch on as soon as the EP-19xx has
switched on the 24-V supply.
GFK-2956A
Cat. 4
DIN EN ISO 13849-1
PLe
DIN EN ISO 13849-1
SIL3
IEC 62061/61508
0
EN 60204-1
• Dual-channel monitoring
• Cross-connection detection
• Start buton
• Monitoring of external contactors (EDM)
• Emergency stop button
• Cable-pull switch, latching
• Manual reset
• Autostart is possible if the NC circuits from
K3 and K4 are attached to 3.3 and 3.4.
November 2017
Chapter 7. Example Applications
45