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Figure 4-2 Connecting an RS485 communications cable
Port
Silk Screen
Description
COM1, COM2, and
COM3
+
RS485A, RS485 differential
–
RS485B, RS485 differential
signal–
Step 2 If devices need to be cascaded, cascade the devices and then connect them to the
SmartLogger.
NO TICE
● You are advised to connect fewer than 30 devices to each RS485 route.
● The baud rate, communications protocol, and parity mode of all devices on an
RS485 cascading link must be the same as those of the COM port on the
SmartLogger.
SmartLogger3000
User Manual
4 Cable Connections
Issue 10 (2022-08-20)
Copyright © Huawei Technologies Co., Ltd.
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