High-Performance & Dependable Ethernet Equipment for modern IoT & connectivity
- Support for RS-232, RS-485, and RS-422 interfaces
- Support for full/half-duplex communication
- Asynchronous transmission for point-to-point applications
- SC/FC/ST optical interfaces available upon request
- Built-in power adapter with wide-range AC 100-240V input
- Plug-and-play design for easy maintenance
- One-key port isolation configuration
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Quality Certifications
Description
The SH-277 fiber optic to serial converter supporting asynchronous RS-232, RS-485, and RS-422 communication interfaces. It is the optimal solution for connecting Remote Terminal Units (RTUs) to Hosts or Distributed Data Acquisition System (SCADA) controllers.
Key Features:
- Supports multiple asynchronous communication protocols: RS-232, RS-485, and RS-422.
- Allows simultaneous mixed use of two RS-232, RS-485, or RS-422 interfaces.
- Supports 2-wire (half-duplex) RS-485 and 4-wire (full-duplex) RS-422 operation modes.
RS-485 Mode Enhancements:
TXD/SD data transmission control improves compatibility with various software systems and simplifies control mechanisms.
Fiber Optic Connectivity:
- Enables full-duplex or half-duplex communication between asynchronous serial ports via fiber optic links.
- Communication distances up to 4km (multi-mode) or 20km (single-mode).
- Maximum data rates:RS-232: Up to 115.2 KbpsRS-485/RS-422: Up to 460 Kbps
Flexible Interface Mixing:
- Allows seamless connection between devices with different electrical standards (e.g., RS-232 to RS-485/RS-422).
- Functions as both an RS-232 to RS-485/422 converter and an optoelectronic isolator.
- Provides excellent EMI/RFI protection for reliable operation in industrial environments.
Order Guide
Technical Specifications
| Category | Parameter | Specification |
|---|---|---|
| RS-232 Interface Characteristics | Standard | Three-wire interface with ±15KV ESD protection |
| Maximum Baud Rate | 115.2Kbps | |
| RS-485/422 Interface Characteristics | Port Technology | Adaptive technology (auto baud rate adjustment) |
| Protection | ±15KV ESD and 600W surge protection per line | |
| Polling Support | Up to 32-point environments | |
| Asynchronous Transmission | Maximum Baud Rate | 460Kbps (point-to-point) |
| Wavelength | Multimode | 1310nm |
| Singlemode | 1310nm and 1550nm | |
| Transmission Distance | Multimode | 4 kilometers |
| Singlemode | 20 kilometers | |
| Optical Fiber Interfaces | Standard | ST-type (SC/FC optional) |
| Electrical Interfaces | RS-232 | Terminal block connector |
| RS-485/422 | Terminal block connector | |
| Power Supply | Input Voltage | DC9-48V |
| Current | ≤200mA | |
| Interface | 1×5.5×2.5mm DC socket | |
| Environmental Specifications | Operating Temperature | -10℃ to +65℃ |
| Operating Humidity | 5%-90% (non-condensing) | |
| Storage Temperature | -40℃ to +75℃ | |
| Storage Humidity | 5%-95% (non-condensing) | |
| Indicator Lights | PWR | Power indicator |
| TXD | Optical data transmission indicator | |
| RXD | Optical data reception indicator | |
| MTBF | Parameter | 500,000 hours |
Terminal Block Pin Assignment
| Terminal Block (PIN) | Signal Definition | RS-422 Full-Duplex Wiring | RS-485 Half-Duplex Wiring |
|---|---|---|---|
| 1 | T/R+ | Transmit (A+) | RS-485 (A+) |
| 2 | T/R- | Transmit (B-) | RS-485 (B-) |
| 3 | RXD+ | Receive (A+) | Empty |
| 4 | RXD- | Receive (B-) | Empty |
| 5 | TXD | RS-232 (Transmit) | – |
| 6 | RXD | RS-232 (Receive) | – |
| 7 | GND | RS-232 (Ground) | – |
| 8 | VCC | Power Input (DC9-48V) | – |
| 9 | GND | Ground | – |
| 10 | ETH | Earth Ground | – |
Additional Information
Customize & Inquiry
We offer customized IoT Ethernet devices and quotes based on your order quantity. For customization or purchase needs, please send your requirements to us.
Product Datasheet
We provide the data sheet for our IoT Ethernet devices (including specs and protocol support) to help you check project compatibility. Add to cart for instant access.
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