GE RSTi-EP, Руководство по функциональной безопасности

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Chapter 7 . Example Applications
GFK-2956A November 2017 63
7.12 Dual-channel Safety Door Monitoring with Automatic Reset
and Controlled Shutdown and Emergency Stop
Achievable safety rating Cat. 4 DIN EN ISO 13849-1
PLe DIN EN ISO 13849-1
SIL3 IEC 62061/61508
Stop category 0 EN 60204-1
Features •
Dual-channel monitoring
•
Cross-connection detection
•
Automatic reset
•
Monitoring of external contactors (EDM)
Safety sensor/operating
mechanism •
Emergency stop button
•
Position switch
•
Optional: brake
Notes •
Autostart is also possible if the NC
circuits from K3 and K4 are connected
to 3.3 and 3.4
•
As soon as the enabling on the
frequency converter is withdrawn, the
converter must execute a controlled
shutdown
•
Exclusion of fault: No external energy
might be fed into the control line of the
brake (such as caused by cable fault)
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, 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 safety door contact 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.
After opening the safety door and the expiration of the delay time set in the EP-1922, the
springoperated interlock can be activated with the unlock button and the safety door can be opened.
When the power supply is turned off, the safety door cannot be opened if the locking
mechanism is engaged. We recommend using switches with mechanical unlocking capabilities.
The EP-19xx module switches the 24-V power supply for the following modules within the safety
segment if:
•
Emergency stop button is unlocked
•
Safety door is closed
•
Feedback circuit (NC contacts of K3 and K4) is closed
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. To reset the system when switching on the power, simply press the
reset button.