1. Introduction
This manual provides detailed instructions for the Waveshare USB to RS485 Converter. This industrial-grade converter is designed for reliable and stable communication between USB and RS485 devices, featuring robust protection circuits and an original FT232RL chip for enhanced compatibility and performance. It is suitable for various industrial control equipment and applications requiring high communication reliability.
Image: The Waveshare USB to RS485 Converter, showcasing its compact design and USB-A connector on one end, and the RS485 screw terminal block on the other. Three indicator LEDs (PWR, TXD, RXD) are visible on the top surface.
2. Package Contents
Please verify that all items listed below are included in your package:
- 1x Waveshare USB to RS485 Converter
- 1x USB-A Male to Female Cable
- 1x Small Screwdriver (for terminal connections)
Image: A visual representation of the package contents, including the USB to RS485 converter, a USB extension cable, and a small screwdriver for wiring the RS485 terminals.
3. Key Features
The Waveshare USB to RS485 Converter incorporates several features for reliable and secure operation:
- USB to RS485 Bidirectional Conversion: Supports seamless two-way data flow.
- Original FT232RL and SP485EEN Chips: Ensures fast communication, stability, reliability, and broad compatibility.
- Onboard TVS (Transient Voltage Suppressor): Effectively suppresses surge voltage and transient spike voltage, providing lightningproof and anti-electrostatic protection.
- Onboard Resettable Fuse and Protection Diodes: Guarantees stable current/voltage outputs, offering over-current/over-voltage protection and improved shock resistance.
- 3 LED Indicators: Provides visual feedback for power (PWR) and transceiver status (TXD, RXD).
Image: An infographic summarizing the key features of the converter, including bidirectional conversion, FT232RL/SP485EEN chips, TVS protection, resettable fuse, and LED indicators.
4. Hardware Overview
Understanding the components of your converter is essential for proper use.
4.1 Internal Components and Protection Circuits
Image: An exploded view showing the internal components of the converter, highlighting the FT232RL chip, SP485EEN chip, TVS protection circuit, resettable fuse, lightningproof tube, and ESD protection circuit.
4.2 Working Status Indicators
The converter features three LEDs to indicate its operational status:
- PWR (Power): Lights up red when the device is connected to a USB port and receives power.
- TXD (Transmit Data): Blinks red when data is being transmitted from the USB side to the RS485 side.
- RXD (Receive Data): Blinks red when data is being received from the RS485 side to the USB side.
Image: A diagram illustrating the three LED indicators (PWR, TXD, RXD) and their functions, along with the outline dimensions of the converter in millimeters.
5. Setup and Connection
Follow these steps to set up and connect your USB to RS485 converter:
- Driver Installation: The FT232RL chip typically supports automatic driver installation on most modern operating systems (Windows, macOS, Linux). If drivers are not installed automatically, please refer to the Waveshare product page or FTDI website for specific driver downloads.
- USB Connection: Connect the USB-A male connector of the converter directly to an available USB port on your computer or host device. The PWR LED should light up red, indicating power.
- RS485 Wiring: Use the provided screwdriver to connect your RS485 device to the screw terminal block on the converter. Ensure correct polarity:
- GND: Connect to the ground of your RS485 device.
- A+: Connect to the A+ line of your RS485 device.
- B-: Connect to the B- line of your RS485 device.
- Verify Connections: Double-check all connections to ensure they are secure and correctly wired.
Image: A diagram illustrating the connection of the USB to RS485 converter to a computer and multiple RS485 devices, highlighting the transmission distance capabilities (up to 1.2km for RS485, 5m for USB) and the recommendation to use repeaters for more than 16 devices.
6. Operating Instructions
Once connected, the converter operates automatically for data transceiving. The LEDs provide real-time status:
- When your computer sends data to the RS485 device, the TXD LED will blink.
- When the RS485 device sends data back to your computer, the RXD LED will blink.
Ensure your software application is configured to use the correct serial port (COM port) assigned to the USB to RS485 converter by your operating system. The baud rate can range from 300bps to 921600bps, depending on your application requirements.
7. Specifications
Detailed technical specifications for the Waveshare USB to RS485 Converter:
Image: A table detailing the product specifications, including host port, device port, baudrate, USB and RS485 characteristics, LED indicators, operating environment, and supported operating systems.
| Category | Specification |
|---|---|
| Product Type | Industrial Grade USB to RS485 converter |
| Host Port | USB |
| Device Port | RS485 |
| Baudrate | 300bps - 921600bps |
| USB Interface | |
| Operating Voltage | 5V |
| Connector | USB-A |
| Protection | 200mA self-recovery fuse, ESD protection |
| Transmission Distance | About 5m |
| RS485 Interface | |
| Connector | Screw terminal |
| Pins | A+, B-, GND |
| Direction Control | Hardware automatic control |
| Protection | 600W lightningproof and surge-suppress, 15KV ESD protection (onboard 120R balancing resistor) |
| Transmission Distance | About 1.2km (low rate) |
| Transmission Mode | Point-to-multipoints (up to 32 nodes, repeaters recommended for >16 nodes) |
| LED Indicators | |
| PWR | Red power indicator, lights up when USB connected and voltage detected |
| TXD | Red TX indicator, lights up when USB port sends data |
| RXD | Red RX indicator, lights up when device port sends data back |
| Operating Environment | |
| Temperature | -15°C ~ 70°C |
| Humidity | 5%RH ~ 95%RH |
| Operating System | Mac, Linux, Android, WinCE, Windows 11 / 10 / 8.1 / 8 / 7 / XP |
8. Troubleshooting
If you encounter issues with your Waveshare USB to RS485 Converter, consider the following:
- No Power (PWR LED off): Ensure the converter is securely plugged into a functional USB port. Try a different USB port or computer.
- No Data Transmission/Reception (TXD/RXD LEDs not blinking):
- Verify that the correct drivers are installed for the FT232RL chip.
- Check the RS485 wiring for correct polarity (A+ to A+, B- to B-, GND to GND) and secure connections.
- Confirm that your software application is configured to use the correct COM port and baud rate.
- Ensure the RS485 device is powered on and functioning correctly.
- For multi-point RS485 networks, check for proper termination resistors and addressing.
- Intermittent Communication: This could be due to electrical noise. Ensure proper shielding for long RS485 cables and consider using a repeater for distances exceeding 1.2km or for more than 16 devices.
9. Maintenance
The Waveshare USB to RS485 Converter is designed for durability and requires minimal maintenance:
- Keep the device clean and free from dust and moisture.
- Avoid exposing the converter to extreme temperatures or direct sunlight.
- Do not attempt to open the casing, as this may void any potential warranty and could damage the internal components.
10. Support and Warranty
For technical support, driver downloads, or further inquiries, please visit the official Waveshare website or contact their customer service. Specific warranty information may be available on the product packaging or the Waveshare support portal.
For additional resources, you may visit the Waveshare Store on Amazon.
