RM4U USB Controlled Relay Module 4-Channel
RM4U is a 4-channel USB-controlled relay module. It can be used to control electrical devices remotely from a PC over a USB port such as lamps, motors, and locks. RM4U features a wide operating voltage range (9-40V) and supports serial communication baud rate speeds starting from 2400 up to 115200 bps. RM4U module is well protected, filtered, and fully isolated.
Features
- Supports Windows XP, 7, 10, and 11.
- Supports 4 relay outputs.
- Wide operating voltage range: 9~40 DCV.
- Control: Serial communication.
- Driver: CH340.
- Supported baud rates: 2400, 4800, 9600, 14400, 19200, 28800, 38400, 57600, 76800, and 115200.
- Interface: USB type B connector.
- Simple control protocol: Just two-character commands.
- All outputs are optically isolated.
- Both normally open and normally close relay contacts are available.
- Reverse polarity protection.
- On-board DC power filter.
- Power LED indicator.
- Serial communication LED status.
- LED indicator for each relay.
- Mounting: Four (Ø 3.5mm) mounting holes for easy installation.
- Dimensions: 144 X 55 X 21mm.
PINOUT
Specifications
| Parameter | Value |
|---|---|
| Model | RM4U |
| Channels | 4 |
| Operating Voltage | 9~40VDC |
| Control Interface | USB (CH340 USB-to-UART) |
| Supported Baud Rates (bps) | 2400, 4800, 9600, 14400, 19200, 28800, 38400, 57600, 76800, 115200 |
| Command Protocol | Simple two-character serial commands |
| Output Type | Opto-isolated SPDT relays (NO/NC) |
| Indicators | Power LED, Serial activity LED, 4× Relay LEDs |
| Connector | USB Type-B (control); screw terminals for relay/load wiring |
| Mounting | 4× Ø3.5mm mounting holes |
| Dimensions | 144mm x 55mm x 21mm |
Applications
- PC-based automation and test rigs for switching lamps, motors, solenoids and small actuators.
- Home and building control systems requiring isolated relay outputs driven from a computer.
- Remote switching for lab equipment, bench setups, and field prototypes.
- Integration with microcontroller systems via serial bridge for logging, timed switching or sequencing.
- Replacement or upgrade in control panels where USB control and optical isolation are required.
Package Contents
- 1x RM4U USB Controlled Relay Module 4-Channel.
Documents
| Manual | RM4U |
