Feature: 1. MAIN PURPOSE: 1 channel optocoupler isolation module, mainly used to detect the existence of 220V AC, which is efficient and practical. 2. OUT AND GND: The input terminal is connected to the signal output OUT, the GND on the board is connected to the power negative pole. 3. LEVEL OUTPUT: The output TTL level can be detected by a single chip computer, 3‑5V power supply, can also be connected to PLC24V level. 4. EASY CONNECTION: The green 2P 5.0 terminal is connected with 220V voltage, and the 3P terminal is connected with single chip computer input. 5. 5PCS IN 1 SET: Including 5pcs optocoupler isolation modules, small and compact, easy to install and replace, has a wide application range. Specification: Item Type: Optocoupler Module Material: PCB Function: Can be used to detect whether 220V AC exists. Package List: 5 x Optocoupler Module Note: 1. After the module is powered on, do not touch any device in the white wire frame on the board2. Please pay attention to power safety because of high voltage