3Com 4500 Getting Started Manual page 26

26 C 2: I
HAPTER NSTALLING THE
Connecting the Earthing
Cable
RPS LED
S
WITCH
Figure 7 RPS Connection to the Switch
NULL
-48 -60V;2 0A
Pinout
When the RPS is connected to the Switch, the circuit breaker in the RPS can be
moved to the closed (on) position and the Switch will be powered by the -48V DC
power.
The -48V DC power will take priority over the AC mains and will power the Switch
if it is connected.
Use the earthing cable that accompanies your Switch if the length is suitable.
Alternatively use the earthing cable specification as defined in Appendix E
"Technical Specifications" on page 79.
The earthing cable is only required if the Switch is powered by the RPS only.
The recommended cable length should not exceed 3 metres (9.84 feet).
The RPS status LED on the front of the Switch 4500 PWR indicates the status of
the RPS and AC supplies as shown in Table 13.
Table 13 RPS LED Colors
Table 14
Color State
Green AC and RPS supply connected.
Yellow AC failed or not connected. RPS supply is ok.
Off There is no RPS supply connected.
+ - N U LL
A
0 V ;2 .0
-4 8 -6
z; 1 .0 A
0 /6 0 H
4 0 V ;5
~
1 0 0 -2
Null
-
+
Cable Tie