ECC500
User Manual
3 Configurations and Port
Issue 05 (2020-03-16)
Copyright © Huawei Technologies Co., Ltd.
22
COM4/12V and COM5/12V ports: Pins 3 and 8 of these two ports provide 12 V DC power.
Therefore, before connecting equipment to the ports, check the equipment pin description
to ensure that pins of the equipment match those on the ports, preventing damage to ports
or the equipment.
If an RS232 port transfers to an RS485 port and connects to an RS485 communications
card, one COM port connects to only one RS232 device. The recommended COM port is
COM1, COM2, or COM3.
The internal circuit design of the RS485 communication card allows its COM port to support
two-wire RS485 and four-wire RS422, eliminating the need to cascade cables, as shown in
Figure 3-5
Compatibility of the RS485 interfaces
3.2.4 AI/DI Expansion Card
The AI/DI expansion card provides four AI/DI input ports to connect monitoring sensors and
provide the DO control function.
shows ports on the front panel of the AI/DI
expansion card.