Huawei ECC500 User Manual page 28

ECC500
User Manual
Silk Screen
ALM
COM4/12V
COM5/12V
Table 3-7
Table 3-7 Description of ports on the front panel of the RS485 expansion card
Silk Screen
COM1, COM2, and COM3
COM4/12V and COM5/12V
Issue 03 (2020-01-06)
Color Meaning
Alarm
Red
indicator
Port power
Green
output
indicator
describes the ports on the front panel of the RS485 expansion card.
Copyright © Huawei Technologies Co., Ltd.
Status
Blinking (0.125
second on and
0.125 second off)
Off
Steady on
Steady on
Off
Port Description
Connect to intelligent equipment, such as the UPS, AC
transfer switch (ATS), and air conditioning unit (ACU).
Pin definition:
 1: A
 2: B
 4: A

5: B
Provide DC outputs of 12 V (actual range: 12.8–15 V),
400 mA to devices such as AI/DI modules and intelligent
T/H sensors.
Pin definition:
 1: A
 2: B
 3: 12 V DC power

4: A
 5: B

8: GND
3 Configurations and Port
Description
The RS485 expansion
card fails to
communicate with the
main control module.
No alarm is generated.
A board alarm is
generated.
The port properly
provides the 12 V DC
output.
The port provides no
12 V DC output.
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