Installation guide

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Cisco IGX 8400 Series Installation Guide, Release 9.3.3 and Later Releases
OL-1165-06
Chapter 3 Installing the IGX
Attaching Peripherals
Figure 3-22 Connecting Modems to an IGX Node
Connecting the Power Supply Monitor
The power supply monitor (PSM) is a connector with outputs that signal an AC power supply alarm.
Cisco provides no equipment that connects to the PSM connector, so user-supplied equipment is
necessary. Refer to the Cisco IGX 8400 Series Provisioning Guide for a description of the PSM outputs.
Using the Power Supply Monitor Connector
The Power Supply Monitor (PSM) is an RJ-45 connector with the following pinout:
• Pin 1 = Digital Ground
• Pin 2 = AACFAIL*_OUT
• Pin 3 = BACFAIL*_OUT
Each AC power supply provides an open collector output that goes low if an AC power failure occurs.
The inactive state of the status signals is high on the SCM. The signals go into an ALS244 driver, the
outputs of which are connected directly to the RJ-45 connector as well as circuitry that communicates
the status to the control card. To use the PSM connector, you need a device that responds with a fail
condition when a “0” TTL logic level is present on pin 2 or pin 3.
SCM
External
clock
(DB-15)
Control
terminal
(DB-25)
Auxiliary
port
(DB-25)
LAN AUI
(DB-15)
Fail (red)
Active (green)
PSM
H8361
RS-232
Auto-answer
modem
Auto-dial
modem
RS-232