Industrial 4-Channel Relay Module
4-channel relay module with Modbus RTU protocol over RS485 or RS232. Controls AC and DC loads independently from a host computer.
4-channel relay module with Modbus RTU protocol over RS485 or RS232. Controls AC and DC loads independently from a host computer.
| Pin | Position | Type |
|---|---|---|
| + | 1 | Power |
| - | 2 | Ground |
| VIN | 3 | Power |
| COM+ | 4 | Control |
| IN1 | 5 | Signal |
| IN2 | 6 | Signal |
| IN3 | 7 | Signal |
| IN4 | 8 | Signal |
| COM- | 9 | Ground |
| NO1 | 10 | Signal |
| COM1 | 11 | Signal |
| NC1 | 12 | Unknown |
| NO2 | 13 | Signal |
| COM2 | 14 | Signal |
| NC2 | 15 | Unknown |
| NO3 | 16 | Signal |
| COM3 | 17 | Signal |
| NC3 | 18 | Unknown |
| NO4 | 19 | Signal |
| COM4 | 20 | Signal |
| NC4 | 21 | Unknown |
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