Liebert 300 user manual

Summary of the content on the page No. 1

DISCONTINUED
PRODUCT
POWER PROTECTION
OPERATOR’S
MANUAL
Series 300
Three Phase
Uninterruptible
Power System
Load Bus
Synchronization
Option
WARNING
READ BEFORE
HANDLING
OR INSTALLING.
ONLY QUALIFIED
PERSONNEL
SHOULD HANDLE
THIS EQUIPMENT.

Summary of the content on the page No. 2

Table of Contents Section 1 Introduction 1.0 System Description ................................................................................................ 1 Section 2 Theory of Operation 2.1 General Description................................................................................................ 2 2.2 Load Bus Sync Controller ..................................................................................... 2 2.3 Series 300 LBS Module Interface .....................

Summary of the content on the page No. 3

SECTION 1 INTRODUCTION 1.0 SYSTEM DESCRIPTION The Liebert Load Bus Sync™ (LBS) option keeps the output of two independent Uninterruptible Power Systems (UPSs) in sync, even when the two UPSs are operating from two different power sources. Any UPS will typically sync to its own bypass source. As long as both UPSs are tied to the same input and bypass sources, they will automatically stay in sync. However, if the UPSs are operating on batteries, or different backup generators, or asynchronous

Summary of the content on the page No. 4

SECTION 2 THEORY OF OPERATION 2.1 GENERAL DESCRIPTION The Liebert Series 300 Load Bus Sync (LBS) option works by monitoring the sync reference signals of two UPS modules, each equipped with a specially designed interface. The LBS remains dormant until the outputs of the UPS modules drift more than a predetermined amount out of sync. In the event of an out of sync condition, the LBS becomes active and brings the output of both UPS modules back in sync, and then resumes the dormant state. 2.2

Summary of the content on the page No. 5

D. Operates the flashing warning light on the front panel of the slave UPS indicating that the Main Rotary Switch should not be operated while sync is being acquired with the master UPS. 2.4 SYSTEM OPERATION The Series 300 LBS option performs the following functions: A. Continuously senses the phase relationship between the outputs of the two UPS modules that make up the system. B. If the two systems lose sync with each other for more than a predetermined period of time (adjustable from 0.1

Summary of the content on the page No. 6

SECTION 3 OPERATION 3.1 OPERATOR CONTROLS Operation of the LBS has deliberately been kept as simple possible. There are only three controls and five indicator lights on the SERIES 300 LBS Controller enclosure. Each LBS equipped UPS module has one indicator light mounted on the bezel below the front display panel. The indicators are: A. LBS Enabled. Indicates that the LBS circuitry is in the Automatic Mode. B. System Non-Sync. Indicates that the DSS is no longer in sync with the DMS. This ala

Summary of the content on the page No. 7

indicator will be off during the synchronization process and turn back on when the process is completed. When the slave system is in the process of synchronizing to the master system, the Warning Indicator on the slave system will be flashing on and off. This is to warn against operating the Main Rotary Switch. SL-24536 (5/00) Series 300 Load Bus Synchronization 5 DISCONTINUED PRODUCT