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On a switch, after the DC power is transmitted to the PWR module, the PWR module outputs
12 V voltage, and provides power for the entire device.
2.2.2 Working Mode of Non-PoE AC Power Supply Units
The working mode of the S3300 non-PoE AC power supply units is shown in
Figure 2-2
Working mode of non-PoE AC power supply units
Motherboard
GND
12V
PWR1
L N PGND
L: Live line
N: Neutral wire
PGND: PGND cable
GND: Grounding
On a switch, after the AC power is transmitted to the PWR module, the PWR module outputs
12 V voltage, and provides power for the entire device.
2.2.3 Working Mode of PoE AC Power Supply Units
The working mode of S3300 PoE AC power supply units is shown in
Figure 2-3
Working mode of PoE AC power supply units
PWR1
L
N
Motherboard
GND
12V
PGND
PWR2
L N PGND
-53V RTN
L: Live line
N: Neutral wire
PGND: PGND cable
GND: Grounding
RTN: Ground cable
After the PoE power is transmitted to the PWR module, the PWR module outputs 12 V and -53
V voltage, and then the motherboard provides 12 V voltage for the entire device and -53 V
voltage for the powered devices (PDs).
2 Power Supply Unit
Quidway S3300 Series Ethernet Switches
Hardware Description
2-4
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Copyright © Huawei Technologies Co., Ltd.
Issue 01 (2011-01-30)