How to connect the safety relay to the emergency stop button and safety light curtain?
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- Issue Time
- Jun 9,2025
A：
Safety relays can be used as central control modules to integrate multiple safety input devices (such as emergency stop buttons and safety light curtains) into a safety loop. The connection method is as follows:
1. Emergency stop button connection:
Connect the normally closed contact of the button to the input of the safety relay. When the button is pressed, the contact is disconnected, the relay detects the circuit break, immediately cuts off the output, and shuts down the relevant equipment.
2. Safety light curtain connection:
The safety output signal of the light curtain controller (usually PNP or relay normally open contact) is connected to another input channel of the safety relay. When the light curtain is blocked, the output signal is interrupted and the safety relay responds.
3. Output control:
The safety relay will close the output loop and allow the equipment to run only when all input signals are normal. If any input triggers a fault, the output is disconnected.
4. Feedback loop (monitoring normally closed contacts):
It is recommended to add a feedback loop to monitor whether the contactor is reliably released to ensure the redundancy and reliability of the entire safety system.
Through this connection method, the safety relay realizes unified monitoring and control of multiple safety devices and improves the overall system safety level.