Product Introduction
When communication noise and ground loops threaten your industrial network, the Schneider NW-BM85S485 provides robust isolation and reliable data transfer. This multiplexer bridge module belongs to the Modicon Quantum series and uses the Modbus RTU protocol over RS-485. It is designed to withstand harsh environments while maintaining signal integrity.
Technical Specifications
The Schneider NW-BM85S485 delivers key performance metrics essential for dependable automation. Below are the critical specifications:
| Parameter |
Value |
| Protocol |
Modbus RTU over RS-485 |
| Data Rate |
Up to 115.2 kbps |
| Signal Isolation |
Galvanic isolation |
| Operating Voltage |
12–24V DC |
| Power Consumption |
<1W |
| Operating Temperature |
-20°C to +70°C |
| Storage Temperature |
-40°C to +85°C |
| Relative Humidity |
5–95% |
| Enclosure Rating |
IP20 |
| Dimensions (L×W×H) |
100 mm × 50 mm × 25 mm |
| Weight |
4.56 lbs (2.07 kg) |
These parameters ensure the NW-BM85S485 operates efficiently in demanding industrial conditions while minimizing electrical interference.
Industry Applications
The NW-BM85S485 excels in environments where noise immunity is critical. In oil and gas facilities, shielded twisted pair cabling and galvanic isolation prevent ground loops that can corrupt Modbus communications. Water treatment plants benefit from the wide operating temperature range, allowing deployment in outdoor control cabinets. Manufacturing lines rely on the module's low power consumption (<1W) to reduce heat buildup in sealed enclosures, extending component life.
Compatibility & Integration
Designed for the Modicon Quantum platform, the NW-BM85S485 integrates seamlessly with existing RS-485 networks using Modbus RTU. Its RJ45 connector simplifies wiring, and the 4-port multiplexer bridges multiple segments for scalable system expansion. The module supports rack mounting, aligning with standard Quantum backplanes.
Troubleshooting & Common Issues
Common failure points in RS-485 networks include signal degradation over long distances and ground loops. The Schneider NW-BM85S485 addresses these with galvanic isolation and a requirement for shielded twisted pair cable. For reliable operation, ensure proper termination resistors at each end of the bus and avoid exceeding 115.2 kbps data rate. The IP20 enclosure requires a clean, dry environment; keep the module free from dust and moisture.
Selection Guide & Purchasing Advice
Before purchasing the NW-BM85S485, verify that your power supply provides 12–24V DC and that your network uses Modbus RTU. The module comes with a shielded cable for interference protection. For best results, pair it with a compatible Modicon Quantum rack. PLC Source PRO (available at ubest101.myshopify.com) offers genuine Schneider units with verified specifications. Contact us to confirm stock and delivery timelines.