lists the current parameters of each circuit breaker and each power line for the
Table 2-12
Current parameters of circuit breakers and power lines for the PDF (DC PEMB)
Item
Specification
Note
Each circuit breaker
(A1,A2,B1,B2,C1,C2,D1,D
2)
≥ 60 A
To protect power supplies of
different levels, it is
recommended that the
current of the circuit breaker
on the user side should be
greater than or equal to that
of the circuit breaker of the
power module (70 A).
Each power supply
(A1,A2,B1,B2,C1,C2,D1,D
2)
≥60 A
To support the maximum
configuration, it is
recommended that each DC
power line should provide a
minimum of 60 A current.
If the PDF cannot provide 70 A circuit breakers and full configuration is unnecessary,
select the circuit breaker of each DC line using the following formula
(A1,A2,B1,B2,C1,C2,D1,D2):
I = P / (Vin * D * 4)
I: rated current of the circuit breaker of each line on the PDF, in Ampere (A).
P: total power of each device.
Vin: input voltage of the power supply. (38 < Vin < 72)
D: derating coefficient. The recommended coefficient is 0.8.
4: number of input lines on the power module.
describes how to select power cables (a1,a2,b1,b2,c1,c2,d1,d2)
Table 2-13
PEMB cables
Distance from the PDF to
the Device
Power Cables a and b
Shorter than or equal to 15
m
Wire,450/750V,227 IEC
02(RV)16mm
2
,blue,85A
Each power module should
be equipped with one cable
of this type. The cable
length is determined by an
onsite project survey.
HUAWEI USG9500 Series
Hardware Guide
2 Hardware Installation
Issue 03 (2017-12-15)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
323
