Chapter 1: About Arc Guard System; Introduction - ABB Arc Guard System TVOC-2 Installation And Maintenance Manual

Chapter 1: About Arc Guard System

Introduction

Arc Guard System™ TVOC-2 quickly detects an arc and trips the incoming
circuit-breaker. Using light as the main condition, Arc Guard System™ trips
instantaneously. Thanks to this key functional advantage, it overrides all other
protections and delays, which is crucial when reaction times need to be
mesured in milliseconds. The Arc Guard System consists of the Arc Monitor
and optical sensor used for detection of the arc. For some special applica-
tions, an additional current sensing unit can be added. This a measure to
prevent unintentional tripping from strong light, for example, the sun.
The basic function acts in three phases:
• Detection is light passing through an optical sensor.
• Recognition is the Arc Monitor determining the intensity of light.
• Action is the trip contact closing.
About Arc Guard System
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