safety relays block 3TK2825

Product function :-
1. automatic start
2. emergency stop function
3. protective door monitoring
4. step mat monitoring Yes
5. monitored start-up
6. safety-related circuits
7. safety cut-out switch
8. safety cut-out switch
9. position switch monitoring

Applications :-
1. Monitoring the safety functions of the sensors
2. Monitoring of the sensor lines
3. Monitoring of correct functioning of the safety relay
4. Monitoring of actuators for standstill
5. Safety-related shutdown in case of hazards

The 3TK2825 safety relays have three instantaneous redundant enabling circuits with NO functions and two instantaneous one-channel signaling circuits. The enabling circuits are used for safety-related shutdown of actuators; the signaling contacts are used for a non safety-related signaling function. Diagnostics is performed using three LEDs. The 3TK2825 is suitable for monitoring actuator and sensor circuits according to DIN EN / IEC 60204-1 in “Auto start” or “Monitored start” mode. When the EMERGENCY STOP buttons are released or position switches operated and the ON button is pressed, the redundant safety relays, the electronics, and the external contactors are monitored to ensure that they are functioning correctly. If monitoring results in a fault-free state, it is possible to start the device using the ON button (in “monitored start” mode). This closes the enabling circuits. In auto start mode, starting and therefore closing the enabling circuits is initiated directly after closure of the sensor contacts on detection of the fault-free state. With 3TK2825, the ON circuit Y33/34 is checked for short-circuit. That means it is identified as a fault if Y33/34 is closed before the EMERGENCY STOP button is reset. The device also monitors the sensor circuits for cross-circuits. This is done based on various potentials in the sensor circuits.