Siemens RUGGEDCOM RX1500 Installation Manual page 45

RUGGEDCOM RX1500
Installation Guide
• 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)
NOTE
A 15 kΩ pull-up resistor is present on board for the positive terminal.
In noisy environments, additional pull-down resistors may be required for the negative terminal.
Connecting Multiple RS485 Devices
3 5
4
120Ω 10nF
3. Negative
5
120Ω 10nF
4. Positive 5. Shield to Earth (Connected At a Single Point)
Chapter 3
Communication Ports
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