Replacing The Low-Speed Switch (Ls1A-D1) Unit - Fujitsu FLM 150 ADM Maintenance And Trouble Clearing

Maintenance and Trouble Clearing
FJTU-320-515-480
4.8

Replacing the Low-Speed Switch (LS1A-D1) Unit

4.8.1 Overview
This procedure lists the steps required to replace a failed LS1A-D1 Low-Speed
Switch unit.
Refer to Section 2, Plug-In Unit Front-Panel Devices, in this practice for
descriptions of LEDs associated with each plug-in unit, and other front-panel
devices.
Note: LS1A units are not required for middle-speed groups using DS3, STS-1, or OC-3
cards, or in groups not requiring protect units in the low-speed section of the FLM 150 ADM.
WARNING:
During unit replacement, seat all plug-in units with a slow, but firm motion. Do not
push them quickly into the slot. Many critical units have longer power connector pins
to minimize power surges during unit replacement. A slow insertion method will
ensure that plug-in units are not damaged.
WARNING:
Wear an electrostatic discharge wrist strap with a minimum resistance of 1 megohm
when handling FLM units to prevent damage to the units. Before using the wrist strap,
check for opens, shorts and minimum resistance value. If the strap does not pass
these checks, do not use it.
Issue 9, May 1999
4.8: Replacing the Low-Speed Switch (LS1A-D1)
FNC and FNC Customer Use Only
Unit
Vol. ll, Page 480.4-34