SainSmart 4-Channel RS232 Serial Control Relay Switch Board

Parameter: Power Requirements: DC4.5V - 5V, with inside positive, outside negative; or DC9-12V, the first pin connected to VDD, the second pin connected to GND. PCB Dimensions: 71mm X 47mm Input Voltage: Support for 5V and 9-12V PCB Thickness: 1.6mm, made from military FR-4 board material, along with mounting holes. Interface: J5: using 5V power supply input J6: using 9 ~ 12V power input, No.1 pin connect VCC, No.2 connects GND J3 ~ J4 blue terminal: connect user load, it can be used 220V AC or less than 30V DC device, the device current cannot exceed the relay standard load. Each relay has a normally open contact, a normally closed contact, and a common contact. When relay absorbs, the common contact and normally open contact conduct; when the relay releases, public contact and normally closed contact conduct. Package List: 1 x 4-CH RS232 Serial Control Relay Board