POWER LEADER™ Ethernet Gateway
Chapter 2 – Installation
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The Modbus RTU networks should be connected to the RS485 ports on the back of the Ethernet Gateway, as shown in Figure 9.
The RS232 port on the back of the Ethernet Gateway is provided for connection of a dumb terminal to the Gateway. The terminal may be used for configuring the Ethernet Gateway’s settings or for diagnostic purposes. For diagnostic purposes, the Gateway may be set to display all messages and traffic on the terminal so that problems may be tracked down and corrected. To connect a terminal (usually a laptop computer running Windows’ Terminal accessory software) to the Gateway, plug its RS232 cable into the RS232 port on the back of the Ethernet Gateway, as shown in Figure 11.
Figure 9. Connecting an RS485 network to the Ethernet
Gateway.
Per the
Figure 11. Connecting a dumb terminal to the RS232 port.
2–6 Wiring Rules – Modbus Networks
Figure 10. Terminating an RS485 network at the last device.
When wiring Modbus RTU devices to an Ethernet Gateway, follow the wiring rules below to ensure proper configuration. Refer to
1.Up to 31 Modbus devices may be attached to a single Modbus network. RS485 repeaters do not have Modbus addresses, but do count as devices toward the 31 physical devices per network limit.
2.Every device on a single Modbus network must have a unique address. (Devices on different networks may use the same Modbus address, i.e., it is acceptable to have a device addressed as device 10 on Network 1 and another device addressed as device 10 on Network 2.) Use the Modbus address worksheets (at the end of this
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