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Cisco AS5850 Universal Gateway Hardware Installation Guide
78-10573-06 0A
Chapter 1 Cisco AS5850 Product Overview
Field-Replaceable Units
•
Voltage level and current monitoring
The DC-input power supply is designed to prevent any energy hazard during operation. DC power
is first routed to a circuit breaker, followed by a surge protector. In addition, an isolation diode
circuit protects against possible DC-input failure.
The DC-input power supply monitors analog output voltage and current. The battery side of the DC
input is equipped with a 60A circuit breaker, which trips if current reaches peak parameters for
2 seconds. The DC-input power supply circuits are described in
Table 1-12
.
If a PEMF is not properly seated in the Cisco AS5850 backplane, an electronic circuit, or interlock,
trips a breaker in the PEMF and terminates power to the output connectors. This same interlock
provides reverse polarity protection when the system is powered off.
Table 1-11
PEMF MBUS Connector Pin Definitions
Pin
Description
1
Breaker enable
2
5.15 voltage sense to backplane
3
5.15 current sense, between PEMFs
4
5.15 voltage sense return, to backplane
5
ID_P
6
ID_0
7
5.15 volt return, main bus return from backplane
8
5.15 volt return, main bus return from backplane
9
5.15 volt return, main bus return from backplane
10
1.60 volt main power to backplane (2 amps)
11
Mbus_B_H, DATA
12
Mbus_B_L, DATA
13
Return line from pin 1
14
open
15
open
16
48 volt monitor to mbus (not backplane)
17
48 volt current monitor to mbus (not backplane)
18
1.60 volt current monitor, internal to PEMF
19
5.15 volt / 15 amp peak
20
5.15 volt
21
5.15 volt
22
1.6 volt return (2 amp)
23
Mbus_A_H, DATA
24
Mbus_A_L, DATA