3com Switch 4500 PWR 50-Port ユーザーズマニュアル

ページ / 102
28
C
HAPTER
 2: I
NSTALLING
 
THE
 S
WITCH
Table 7   Power Availability
The -48V DC power distribution provides the mechanism to connect to 
the Switch 4500 PWR. The distribution consists of a number of circuit 
breakers and connection terminals for the positive (common) and 
negative -48V outputs. Each Switch 4500 PWR must be individually 
connected to a circuit breaker terminal. 
A battery can also be connected to battery terminals prior to the DC 
power distribution to provide uninterrupted power in order to protect 
against the loss of AC mains power.
3Com’s RPS solution uses -48V DC power distribution. The RPS system 
provides bulk -48V DC power that is separately distributed to a number 
of network switches. 
Each RPS consists of a shelf which can house from one to six rectifiers, a 
Distribution Module and a Management Module.
Connecting the 
Switch to the 
Redundant Power 
System
When connecting the RPS to the Switch, the circuit breaker and 2-core 
cable need to be matched to the power rating of the Switch. Table 8 
shows the recommended circuit breaker and cable rating for the Switch 
4500. The recommended cable length should not exceed 3 metres (9.84 
feet). 
Table 8   Switch 4500 Circuit Breaker and Cable Ratings
WARNING: RPS Manufacturers recommendations must be followed 
when connecting the cable to the RPS.
Rectifiers
1
2
3
4
5
6
No Rectifier 
Redundancy
1500W
3000W
4500W
6000W
7500W
9000W
N+1 Rectifier 
Redundancy
-
1500W
3000W
4500W
6000W
7500W
Circuit Breaker Minimum 2-Core Cable Diameter
Non PoE
6A C type
18 AWG (solid or stranded cable)
PoE
25A C type
12 AWG (solid or stranded cable
)