ABB UniGear ZS3.2 User Manual

SWITCHGEAR PANEL STRUCTURE AND EQUIPMENT INSTALLED 11
3.5.2 Instrument transformers
Current transformers
The current transformers are of the type insulated
in resin and are used to supply the measurement
devices and protection instruments. These
transformers have a wound core with one or
more cores, with performances and accuracy
classes suitable for the installation requirements.
Voltage transformers
The voltage transformers are of the type insulated
in resin and are used to supply measurement
and protection devices. They are available for
fixed assembly or for installation on removable
and withdrawable trucks.
When they are installed on removable or
withdrawable trucks they are fitted with medium
voltage protection fuses. The withdrawable
trucks also allow replacement of the fuses with
the switchgear in service. Truck racking-out with
the door closed automatically operates closure
of a metallic segregation shutter between the
live parts of the switchgear and the instrument
compartment.
3.5.3 Surge arrester
Protection of medium voltage AC networks
against both, multiple atmospheric and switching
overvoltages as well as Very Fast Transients
(VFT). Suitable for instance for the protection
of transformers, cables, motors and other
medium voltage equipment.
3.5.4 Eearthing switch
Earthing switches of Series EK6 are determined
for indoor installation and fitted with snap-action
operating mechanisms for positive high-speed
closing and sufficiently dimensioned to conduct
the rated short-circuit making current when
closed under load. The speed of the snap-action
closing operation is independent controls. The
earthing swithes are supplied as kits with a
pre-assembled active part and corresponding
earthing contacts supplied lose. Correct
installation of these parts in a switchgear panel
results in a functioning earthing earth.
—
3/3 MWK
—
3/4 EK6-4008-280
—
3/3
—
3/4
Advantages
Low residual voltage
• Long protection distance
• High energy input capacity
• Stable U-I characteristics even after
multiple strokes
• Proof against ageing
• Explosion and shatter-resistant design
• Pollution resistant and UV-stable
• Housing resistant to rough handling
• Maintenance free
• Stable against shock and vibration
• High mechanical resistance

ABB UniGear ZS3.2 Specifications

General

Brand	ABB
Model	UniGear ZS3.2
Category	Industrial Electrical
Language	English