MV12
MV12
Vacuum
Vacuum Circuit
Circuit Breaker
Breaker

UP TO 31.5KA FAULT CURRENT

UP TO 2500A CONTINUOUS
CURRENT

UP TO 75KV BIL IMPULSE
WITHSTAND LEVEL

LONG LIFE VACUUM
INTERRUPTORS

LOW MAINTENANCE MAGNETIC
ACTUATOR MECHANISM

SAFETY INTERLOCKS AND
LOCKING FACILITIES ARE
STANDARD

SUITABLE FOR AUTO-RECLOSE
DUTY

STANDARD FEEDER EARTHING
THROUGH CIRCUIT BREAKER

OPTIONAL BUSBAR EARTHING
THROUGH EARTHING TRUCK

OPTIONAL FIXED OR ISOLATABLE
FUSED, BUSBAR OR FEEDER
VOLTAGE TRANSFORMER

DESIGNED FOR MINIMUM COST
OF OWNERSHIP
FM35831
Medelec Switchgear Ltd.
Manufacturers and suppliers of Medium Voltage Switchgear,
Sub-stations and Electrical Equipment
MV12
Vacuum Circuit Breaker
The MV12 is the latest metalclad circuit breaker
switchgear from Medelec Switchgear Limited. It
has a continuous current rating of up to 2500A
and a fault level rating of 31.5kA for 3 seconds.
The fixed housing contains the busbars, current
transformers, protection and instrumentation.
Fixed or isolatable voltage transformers can be
attached to either cable connections or the
busbars to give a full range of measurement and
metering capability.
Feeder earthing is achieved by circuit breaker
transfer.
The moving portion, which is removable for
system maintenance or testing, contains the
vacuum interrupters and magnetic actuator.
The circuit breaker is isolated from the fixed
housing by horizontal movement of the truck.
Final positioning of the truck is by means of a
racking screw, which ensures easy insertion and
security in service.
PROVEN TECHNOLOGY
Vacuum interruption is established as the
predominant
technology
for
current
interruption at distribution voltages.
It
requires smaller contact movement and less
mechanical energy than other methods. This
minimises stresses on the equipment, and
therefore helps to maximise longevity and
reliability.
The equipment is designed to meet the
required impulse levels (up to 75kVp) through
sophisticated component design.
This
simplifies
assembly
and
installation,
maximising reliability.
Medelec has supplied high quality synthetic
moulded insulation components of the type
used in MV12 to industrial and power utility
users over many years.
MAGNETIC ACTUATOR AND ELECTRONIC
CONTROLLER
The vacuum interrupters are opened and
closed by means of a magnetic latched
actuator, incorporating mechanical safety
interlocks and a manual tripping mechanism.
The actuator is electronically controlled to
provide optimum opening and closing
responses. The energy for operation is stored
electrically in a capacitor.
MV12
Vacuum Circuit Breaker
BUILT-IN SAFETY
ADAPTABILITY TO USER NEEDS
Operator and equipment safety are key
features of the MV12. Mechanical interlocks
ensure that users follow the correct
procedures.
The flexibility of the MV12 design allows it to be
customised to meet the needs of individual users.
Such interlocks ensure that the circuit breaker
trucks cannot be removed or replaced with the
circuit breakers closed ensuring current is not
made or broken by truck movement.
When the moving portion is removed,
padlockable earthed metal safety shutters
automatically cover the live fixed primary
contacts to protect personnel.
The MV12 is designed with a number of
compartments, segregated by metal sheets, to
ensure that any faults that may occur are
contained.
Vacuum technology gives a very rapid interruption
of fault current and virtually instantaneous recovery
of dielectric strength. This makes the MV12 ideal for
fast auto-reclose duty and for breaking faults with
high frequency transients.
INSTALLATION SIMPLICITY
The cable box, which gives easy access to cable
termination, and the straightforward method of
connecting units ensures that installation and
extension of switchboards is as trouble free as
possible.
The low energy of mechanical shocks in operation
result in lighter foundation requirements.
With the moving portion removed, high voltage
cable testing and current injection can be carried
out using test bushings inserted into the unit
primary connections.
CIRCUIT BREAKER COMPARTMENT
CABLE COMPARTMENT
MV12
Vacuum Circuit Breaker
ASSURED QUALITY
Medelec Switchgear Ltd. follows ISO9001:2008
approved quality system. The MV12 is
manufactured to IEC 62271.
Vacuum interrupters are sealed for life, minimising
the need for manual intervention and thus the
possibility of human error. Careful selection of
materials in the operating mechanisms minimises
wear and maximises service life.
The use of specially selected zinc coated steels,
and hard, corrosion resistant polyester paint
minimises corrosion and further reduces long term
ownership costs.
MV12
Vacuum Circuit Breaker
DESIGN LAYOUT
TECHNICAL SPECIFICATIONS
Rated Current
800A
Fault Rating
Lightning
Impulse
Rated Frequency
General
1250A
2000A
(2500A with forced ventilation).
Up to 31.5 kA/3s
75kV
50Hz
Busbar Rating
1250A or 2500A
IP Rating
IP4X IEC60529
Standards
IEC 62271
Power Cables
Cable Termination
Up to 2x3-core or 6x1-core
Bottom or Top Entry
Control Cables
Fixed Portion
345kg
Circuit Breaker
17kg
Height
Width Feeder
Unit
Width Bus
Section
Depth
Up to 3x3-core or 12x1-core
Typical Unit Weights
400kg
180kg
515kg
300kg
1980mm
Dimensions
1980mm
1980mm
630mm
630mm
920mm
930mm
930mm
1380mm
1900mm
1900mm
1900mm
MV12
Vacuum Circuit Breaker
MEDELEC SWITCHGEAR LTD
Head Office:
BLB033 Bulebel Industrial Estate,
Zejtun ZTN 3000,
PO Box 20 Paola, PLA 1001,
Malta.
Tel.: (+356) 21693750, 21693753
Fax.: (+356) 21693754
e-mail: info@medelec.com.mt
http://www.medelec.com.mt
Libya Office:
Madaris El Funun W Assanaqa,
Building 82, Flat 9,
1st September Street,
Tripoli,
Libya.
Tel. & Fax.: (+218) 21 4444050
July 2010