Motorola Starline SG 2000 - Power Supply

2-4 Overview
SG 2000 Installation and Operation Manual
Power Supply
The SG 2000 power supply (SG2-PS2) is located in the housing lid to optimize heat transfer and to
balance the thermal load between the base and the lid. For high reliability or redundancy
applications, two power supplies can be used. An umbilical cord connects the SG2-PS2 to the lid
motherboard (LIDB).
A flexible power-distribution design enables you to power the node from any of the four RF ports.
Using fuses and shunts you can configure the node to distribute power to the remaining active ports.
You can also power the node locally through the ac only port (port 2) while a second cable-plant
power supply loops through the other two main RF ports.
The power supply includes a heavy-duty, gas discharge tube surge protector located on the amplifier
module. You can replace this surge protector with the optional FTEC surge protector. The FTEC
triggers at approximately 230 V and presents a short circuit to the line during periods of over
voltage. After the ac input voltage returns to normal, the FTEC returns to its open-circuit state. This
provides the node with a level of protection against surge currents on the ac line. The same protector
is used for both supplies unless the split ac-feed option is implemented; then, the secondary or
redundant power supply is protected by a conventional heavy-duty gas discharge tube.
The 20-ampere fuses are installed at the factory to provide power passing to additional amplifiers.
Section 3, “Bench Setup,” discusses fusing options that are also diagrammed in Figure 3-1.
Figure 3-2 illustrates the location of the fuses.
The SG 2000 optical node can be powered from either 60 Vac or 90 Vac system power supplies. The
unit is shipped from the factory set for 60 Vac powering. For systems equipped with 90 Vac
powering, the suitcase jumper on the dc power supply can be repositioned to optimize the supply
start-up voltage for the higher input range. Section 3, “Bench Setup” provides a description of this
procedure.
Figure 2-4 illustrates the SG2-PS2 power supply:
Figure 2-4
SG2-PS2 power supply
SG2-PS2
CAUTION
NO USER SERVICEABLE PARTS INSIDE ASSEMBLED IN MEXICO
SEE INSTALLATION MANUAL FOR SERVICE
VOLTAGES IN EXCESS OF
300 VOLTS AR E PRESENT
UNDER COVER AND MAY
BE PR ESENT AFTER POWER
IS REMOVED
LO HI
24V 5V
ADJ
TEST
POINT
TEST
POINT
The optional SG2-PS power supply is required to support DS-SG2-DRT-2X/A transmitters in a
redundant configuration. The SG2-PS2 and SG2-PS power supplies are interchangeable.