Features 1、20 CHANNEL RELAY: 2 channel digital input (PNP active high), 1 channel 0‑20MA current analog input, 1 channel 0‑10V voltage analog input, 20 channel 10A relay switch output. 2、COMMAND MODE: Support standard commands, command 1 (default) write 06/16 read 03, command 2 (solder M0 jumper) write 05/06/15/16 read 01/02/03/04. 3、MULTIPLE FUNCTIONS: With hardware reset function and TVS surge protection, the default baud rate is 9600BPS, can be selected by Command 2400 4800 9600 19200 38400 57600 115200BPS. 4、CHECK FUNCTION: Parity check can be no parity, even check and odd check, the time of data transmission and return can be set, the maximum value is 1000ms. 5、WIDE APPLICATION: This relay module can be used in smart home, home automation, PTC cameras, surveillance identification systems, network cameras, LED light drivers, etc. Specification Item Type: Relay Control Board Backboard Length: Approx. 240mm / 9.4in Insulation Grade: Flame retardant VO grade Backboard Length: Suitable for 239mm PCB board Mounting: DIN35 and C45 Rails Standby Current: All relays off 14MA, 1 relay on 40MA, 2 relays on 69MA, 3 relays on 95MA, 4 relays on 122MA, 5 relays on 149MA, 6 relays on 174MA, 7 relays on 200MA, 8 relays turn on 226MA, and so on Package List 1 x Relay Control Board