1. Introduction
This manual provides instructions for the Eletechsup 2-Channel RS232 Relay Board, designed for remote control applications via USB PC UART COM serial ports. It details the board's features, specifications, setup procedures, and operational commands.
1.1 Package Contents
- 1 x DC 5V-12V 2-Channel RS232 Relay Board
2. Specifications
- Module Type: 2 Channel Relay Module
- Power Input: DC 5V or DC 7-12V (Recommended 7.5V-9V)
- Control Interface: PC Serial ports RS232
- Power Indicator: LED lights
- Output Indication: Relay output with LED indicators
- Communication Protocol: UART protocol
- Baud Rate: 9600kbps
- Data Bits: 8
- Stop Bit: 1
- Parity: None
- Data Frame: Each data frame contains eight bytes. Two-way data transmission.
- Dimensions: 71mm x 47mm x 19mm
- Weight: 45g
- Connector Type: Through Hole
- Contact Material: Copper Alloy
- Contact Type: Normally Closed
- Current Rating: 1 Amps
- Mounting Type: Flush Mount
- Coil Voltage: 12 Volts
3. Setup and Wiring
The Eletechsup 2-Channel RS232 Relay Board can be powered by either 5V DC or 7-12V DC. Ensure correct polarity and voltage to prevent damage. The board connects to a PC via an RS232 serial port, often requiring a USB to RS232 adapter.
3.1 Power Input Options
The board supports two main power input configurations:
3.1.1 DC 5V Control Circuit
For applications requiring a 5V DC power supply. The "LOAD" can be various AC or DC equipment such as LED lights, fans, or motors.
3.1.2 DC 7-12V Control Circuit
For applications requiring a 7-12V DC power supply (9V recommended). Similar to the 5V setup, the "LOAD" can be various AC or DC equipment.
3.2 Board Components Overview
4. Operating Instructions
The relay board is controlled via a serial port using specific UART protocol commands. Communication parameters are 9600kbps baud rate, 8 data bits, one stop bit, and no parity. Each data frame consists of eight bytes for two-way data transmission.
4.1 Control Commands
The following commands are used to control the relay channels:
4.1.1 Reading Relay Status (On/Off)
To read the current status of a relay channel, send the corresponding 8-byte hexadecimal command.
| Channel | Command (Hex) |
|---|---|
| Channel 1 | 55 56 00 00 00 01 00 AC |
| Channel 2 | 55 56 00 00 00 02 00 AD |
| Channel 3 | 55 56 00 00 00 03 00 AE |
| Channel 4 | 55 56 00 00 00 04 00 AF |
Note: The provided product is a 2-channel relay board. Commands for Channel 3 and 4 are listed for reference but may not be applicable to this specific model.
4.1.2 Opening a Relay (COM connects to NO)
To activate a relay, connecting its Common (COM) terminal to its Normally Open (NO) terminal, send the following 8-byte hexadecimal command.
| Channel | Command (Hex) |
|---|---|
| Channel 1 | 55 56 00 00 00 01 01 AD |
| Channel 2 | 55 56 00 00 00 02 01 AE |
| Channel 3 | 55 56 00 00 00 03 01 AF |
| Channel 4 | 55 56 00 00 00 04 01 B0 |
Note: The provided product is a 2-channel relay board. Commands for Channel 3 and 4 are listed for reference but may not be applicable to this specific model.
4.1.3 Closing a Relay (COM disconnects NO, connects to NC)
To deactivate a relay, disconnecting its Common (COM) terminal from Normally Open (NO) and connecting it to Normally Closed (NC), send the following 8-byte hexadecimal command.
| Channel | Command (Hex) |
|---|---|
| Channel 1 | 55 56 00 00 00 01 02 AE |
| Channel 2 | 55 56 00 00 00 02 02 AF |
| Channel 3 | 55 56 00 00 00 03 02 B0 |
| Channel 4 | 55 56 00 00 00 04 02 B1 |
Note: The provided product is a 2-channel relay board. Commands for Channel 3 and 4 are listed for reference but may not be applicable to this specific model.
4.2 Demonstration Video
Watch this video for a demonstration of controlling a similar relay board using serial commands.
Video demonstrating the use of serial port commands to control a multi-channel relay board. It shows a serial port tester application sending hexadecimal commands to activate and deactivate relays, with corresponding LED indicators on the board.
5. Maintenance
The Eletechsup 2-Channel RS232 Relay Board is designed for low maintenance. Keep the board clean and free from dust and moisture. Avoid exposing it to extreme temperatures or direct sunlight. No user-serviceable parts are inside.
Regularly check all connections for secure fit to ensure reliable operation.
6. Troubleshooting
6.1 No Power Indication
- Check Power Supply: Ensure the DC 5V or 7-12V power supply is correctly connected and providing the specified voltage.
- Verify Polarity: Confirm that the power input polarity is correct.
- Inspect Connections: Check for loose or damaged power connections.
6.2 No Relay Response
- Serial Port Connection: Ensure the RS232 connection to the PC is secure and the correct COM port is selected in your software.
- UART Settings: Verify that the communication parameters (baud rate 9600kbps, 8 data bits, 1 stop bit, no parity) are correctly configured in your serial terminal software.
- Command Format: Double-check that the hexadecimal control commands are sent exactly as specified in the "Operating Instructions" section.
- Power to Relays: Confirm that the board is receiving adequate power. The power indicator LED should be on.
6.3 Incorrect Relay Operation
- Command Mismatch: Ensure you are sending the correct command for the desired relay channel and action (open/close).
- Load Wiring: Verify that the external loads are correctly wired to the COM, NO, and NC terminals of the relays.
7. Warranty and Support
For warranty information or technical support regarding your Eletechsup 2-Channel RS232 Relay Board, please refer to the product's purchase documentation or contact the seller directly. Keep your proof of purchase for any warranty claims.
Manufacturer: eletechsup
ASIN: B0BQHF3N2D