How Truecharge+ Works - Xantrex Truecharge TC20+ Owner's Manual

Introduction

How Truecharge+ Works

Truecharge+ changes the alternating current (AC) supply from the utility
to the controlled low-voltage, direct current (DC) required to charge the
battery by using high-frequency, switched-mode power conversion
circuits. The high-frequency power conversion method is similar to that
used in power supplies for computers and other electronic equipment. It
results in a significantly smaller and lighter charger than other power
conversion methods allow.
The controlled DC output is fed to three isolations diodes, one for each
battery bank. These diodes isolate the batteries from each other and
prevent current flow from one battery to the others.
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