© Copyright 1995, Best Power Technology, Inc.
RESTRICTED
UTY-0618B
UTY 618
November 1995
Replacing the Internal Batteries in
UNITY
/I™
Models UT3K, UT4K, UT5K, and UT8K
This publication describes how to change the internal batteries in
UNITY
/I models UT3K, UT4K,
UT5K, and UT8K. This procedure is for units with the fuse board mounted below the front panel of
the unit. If the fuse board is inside the chassis, see BEST publication UTY 619. A qualified service
technician must perform this procedure.
If you have any questions or problems while performing this procedure, call BEST Power Worldwide
Service at 1-608-565-2100, or 1-800-356-5737 (U.S.A. and Canada), or call your local BEST office.
Replace batteries with the same series and type battery.
Tools Required (use insulated tools):
DC voltmeter
7/16" nut driver
½" heat shrink tubing or electrical tape
Phillips screwdriver
Diagonal cutters
UNITY
/I User Manual
7/16" box wrench
1/4" nut driver
Personal safety equipment required by local codes (also see the caution on pp. 2 - 3).
Contents
Important Safety Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Section 100: Before Replacing the Batteries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Section 101: Powering Down the UPS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Section 102: Using Battery Maintenance Mode . . . . . . . . . . . . . . . . . . . . . . . 5
Section 200: Removing the Batteries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Section 300: Replacing the Batteries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10