User Manual

ADCP-75-126 • Issue B • April 2002 • Section 2: Description
Page 2-5
© 2002, ADC Telecommunications, Inc.
2.10 Powering
The HU is powered by ± 24 or ± 48 Vdc power. The power is fed to the HU through a screw-
down type terminal strip located on the rear side of the unit. Power to the HU must be supplied
through a fuse panel such as the 20 position PowerWorx fuse panel (available separately). The
power circuit for each HU must be protected with a 3 Amp GMT fuse. An On/Off switch is
provided on the HU front panel.
2.11 Cooling
Continuous airflow for cooling is provided by dual fans mounted on the right side of the HU
housing. A minimum of 3 inches (76 mm) of clearance space must be provided on both the left
and right sides of the HU for air intake and exhaust. An alarm is provided if a high temperature
condition (>50º C/122º F) occurs. The fans may be field-replaced if either fan fails.
2.12 User Interface
The HU user interface consists of the various connectors, switches, terminals, and LEDs that are
provided on the HU front and rear panels. The HU user interface points are indicated in
Figure 2-2 and described in Table 2-1.
Figure 2-2. Host Unit User Interface
Table 2-1. Host Unit User Interface
REF
NO
USER INTERFACE
DESIGNATION
DEVICE
FUNCTIONAL
DESCRIPTION
11/0 On/Off rocker
switch
Provides DC power on/off control.
2PORT 1SC connector
(single-mode)
Connection point for the forward path optical
fiber.
(1) DC POWER 
ON/OFF SWITCH
NOTE: SHOWN WITHOUT
CABLE MANAGEMENT TRAY
(2) 
PORT 1
(3) 
PORT 2
(4) 
PORT 3
(REFERENCE 
ITEMS 5 - 11) 
LED INDICATORS
(12) SERVICE 
INTERFACE 
CONNECTOR
(13) NET IN 
CONNECTOR
(14) NET OUT 
CONNECTOR
(15) ALARM 
OUTPUT 
CONNECTOR
(16) REVERSE 
RF OUT
(17) REVERSE 2 
RF OUT
(18) FORWARD

RF IN
16800-A