Introduction - LEGRAND 3 109 53 Installation Manual

1.1 Overview
Congratulations on your purchase of the LEGRAND maintenance bypass switch 3 109 53.
This switch (MTBS) has been specifically designed to ensure seamless operation of your critical
load during maintenance and testing or during the unlikely event of a UPS failure.
ATTENTION
It is necessary to read the whole manual carefully before doing any operation.
ATTENTION
The maintenance bypass switch 3 109 53 can only be used with the UPS Daker DK 1000 VA -
2000 VA - 3000 VA and Daker DK+ 1000 VA - 2000 VA - 3000 VA manufactured by LEGRAND.
The purpose of this manual is to provide necessary indications to install and use safely the main-
tenance bypass switch.
The reading of these instructions is essential but it cannot substitute the expertise of the technical
personnel who must have had adequate preliminary training.
The MTBS has been built for the applications specified in this manual. For no reason whatsoever
it is allowed to use it for purposes other than those for which it has been designed.
This manual must be kept in a safe, dry place and always be available for consultation. It is suggest-
ed to make a copy and to save it.
The manual is to be considered an integral part of the maintenance bypass switch and there-
fore must be kept for the equipment's useful life cycle.
The information included in this manual must not be disclosed to third parties. Any duplication,
total or partial, not authorized in writing by the Manufacturer obtained by photostatting or any
other method, even electronically, violates the copyright conditions and can be prosecuted by law.
LEGRAND reserves the property rights of this publication and forbids the total or partial
reproduction of it without prior written consent.
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1 Introduction