2
ALL THE INSTALLATION, PuTTING INTO
SERVICE, RuNNING AND MAINTENANCE
OPERATIONS MuST bE CARRIED OuT by
SkILLED PERSONNEL wITH IN-DEPTH
kNOwLEDGE OF THE APPARATuS.
CAUTION
1.Foreword
1.1. Introdution
This publication contains the information needed to install
medium voltage Vmax/w and Vmax circuit-breakers and put
them into service.
For correct use of the product, please read it carefully.
Like all the apparatus we manufacture, the Vmax/w and
Vmax circuit-breakers are designed for different installation
configurations.
However, they do allow further technical and construction
modifications (at the customer’s request) to adapt to special
installation requirements.
For this reason, the information given below may sometimes
not contain instructions concerning special configurations.
Apart from this manual, it is therefore always necessary to
consult the latest technical documentation (circuit and wiring
diagrams, assembly and installation drawings, any protection
coordination studies, etc.), especially regarding any variants
requested in relation to the standardised configurations.
For example, the racking and interlock sections do not apply
to the fixed mount breaker styles. All information in this
booklet was current at the time of printing. unless otherwise
noted, all references in this booklet are determined by viewing
the circuit-breaker from the front.
Only use original spare parts for maintenance operations.
For further information, please also see the technical
catalogue of the circuit-breaker.
1.2. Environmental protection
programme
The Vmax/w and Vmax circuit-breakers are manufactured
in accordance with the ISO 14000 Standards (Guidelines for
environmental management).
The production processes are carried out in compliance
with the Standards for environmental protection in terms of
reduction in energy consumption as well as in raw materials
and production of waste materials. All this is thanks to
the medium voltage apparatus manufacturing facility
environmental management system.
1.3. Vacuum interrupter quenching
principle
Due to the extremely low static interrupter chamber pressure
of 10-4 to 10-8 mbar, only a relatively small contact gap is
required to achieve a high dielectric strength. The vacuum
arc is extinguished on one of the first natural current zeros.
Due to the small contact gap, high conductivity of the metal
vapour plasma, and short arcing time, the associated arc
energy is extremely low, which has advantageous effects
on the life of the contacts and thus on that of the vacuum
interrupters.
