Siemens RUGGEDCOM RX1500 Installation Manual page 38

Chapter 3
Communication Ports
• The shield should be connected to earth ground at a single point to avoid loop currents.
• The twisted pair should be terminated at each end of the chain.
The following shows the recommended RS485 wiring.
2
1
Figure 53: Recommended RS485 Wiring
1. RX1500 Device 2. Common (Isolated Ground)
6. RS485 Devices (32 Total)
32
3 5
4
120Ω 10nF
3. Negative
5
120Ω 10nF
4. Positive 5. Shield to Earth (Connected At a Single Point)
RUGGEDCOM RX1500
Installation Guide
6
Connecting Multiple RS485 Devices