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C U B I C L E
S W I T C H B O A R D S
Cubicle switchboards are of standardised modular construction giving a
great degree of flexibility and good technical performance with
cost effectiveness.
Eaton MEM specialises in producing equipment to the customer’s precise
needs. Thus metering, locking devices, power factor correction equipment,
alternative paint finishes or other non-standard requirements may
be specified.
Designed on a modular concept the Memform switchboard can be
modified or extended in an infinite variety of ways with standard
components - a factor which greatly reduces delivery times.
Both the front and rear access designs are fully cable segregated and
suitable for top and bottom cable entry - with busduct and removable
cable entry plates being provided where appropriate.
Cabling operations are simplified by the provision, as standard, of
removable crossrails etc., thus enabling the ‘laying-in’ of cable tails.
Cable gland location within the fully segregated wiring chamber is
readily adjustable on site, both vertically and fore-and-aft, to suit
specific requirements.
■ Form 4 individual metal compartments as standard
Combinations of the following earthing facilities are available:
A FULL WIDTH EARTH BAR
B GLAND RAIL/GLAND PLATE BONDING
C SUPPLEMENTARY INTERNAL BONDING
D STAR POINT EARTH/NEUTRAL LINK
■ Complies fully with BSEN60 439-1 and IEC60439-1
■ Busbar ratings from 1000A to 10000A
REAR ACCESS SWITCHBOARDS
■ Naturally ventilated
A unit generally more suited to heavy current applications which provides
unobstructed access at the rear for cabling and both front and rear access
for maintenance.
■ Totally enclosed busbars, risers and inter-connections
in sheet steel compartments
■ IP31 as standard
■ Compact modular design to conserve space
■ Front or rear access, with protective devices removable
from the front
■ Vertical/horizontal busbars are ASTA/KEMA Certified
for short circuit performance:
1000A - 50kA for 1 second
1250A - 4000A - 50kA for 3 seconds
1600A - 4000A - 80kA for 1 second
2000A - 10000A - 100kA for 1 second
■ Switchboards can incorporate: ACBs, MCCBs,
fuse-switches, contactors, fuseboards, MCB
boards and other ancillary equipment to
customer specifications
■ A full range of integral power factor
correction equipment, TVSS and controls
■ Wide range of control options includes PLC’s
and BMS interfacing
■ A comprehensive range of metering
■ Locking options include Castell/Fortress door,
shaft and handle locking
■ Versatile enclosure system allows for
future extension of switchboard
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FRONT ACCESS SWITCHBOARDS
Designed for those applications where depth rather than length is
a critical factor in the switchroom. This unit can be installed directly
against a wall and is wholly accessible from the front for cabling
and maintenance.
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CUBICLE CONSTRUCTION
The Memform Form 4 system is designed so that combinations of fuseswitches, MCCBs, ACBs, MCBs, contactors, fuseboard assemblies, power
factor correction, CTs, anti-condensation heaters and other ancillary
equipment can be arranged in vertical stacks, complete with busbars,
risers and interconnections - all enclosed with separation of the busbar
system from functional units, and separation of all functional units from
one another. Incoming and outgoing terminals are also separated from the
busbars and from each other.
A complete switchboard layout can be quickly and easily determined for
combinations of fuse-switches and/or moulded case circuit breakers.
Standard switchboard dimensions are shown below, however arrangements
of switchboards can be accommodated to meet the customers
own specifications.
The basic design includes corner sections for both Rear and Front Access
types, providing facilities for ‘L’ or ‘U’ shaped assemblies.
■ We can provide a complete system design and
application service from our specialist technical
team, based in Birmingham, who are always
available to help and advise on any project.
COMPLIANCE WITH STANDARDS
The Memform Form 4 cubicle switchboard in its standard form complies
fully with BSEN60439-1 and IEC60439-1.
STANDARD STACK DIMENSIONS (NOMINAL)
FOR UP TO 80kA
FRONT ACCESS
REAR ACCESS
Depth
Depth
600mm
Height* 2000mm
or
2300mm
1000mm
Height* 2000mm
or
2300mm
FOR 100kA
REAR ACCESS ONLY
Depth
1200 to 1800mm to meet system requirements
Height* 2300mm
*Not including ventilation cowls
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C U B I C L E
S W I T C H B O A R D S
Choice of
Protective
Device
Individual
Circuit
Monitoring
MCCB Rotary Handle Mechanism
MCB
Distribution
Boards
HRC Fuse
Distribution
Boards
CT
Arrangements
Castell, Handle and
Shaft Locking
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Power
Factor
Control
Contactors
Contractor ‘Friendly’ Connections
Cable tray fitted as standard
MCCB Distribution Boards
Typical Metering
Choice of Incoming Device
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P A C K A G E D
C U B I C L E
S W I T C H B O A R D S
S U B S T A T I O N S
A typical indoor packaged substation comprises a power transformer to
BS171 (IEC176) rated up to 4 MVA and a low voltage switchboard,
assembled together to form a complete unit.
The transformer, generally of Class C air insulated design or resin
encapsulated, is air cooled (AN) and housed in a ventilated sheet steel
enclosure designed to match the front appearance of a MEMFORM
Switchboard. Transformer ratings can be enhanced by the additions of fans
and ratings up to 4MVA (AN) force cooled are available.
A fully supported copper busbar system connects between the transformer
LV secondary terminals and the LV switchboard main incomer, which is
usually an air circuit breaker.
Provision is generally made for MV cable termination into an appropriate
cable box mounted at the rear or side of the transformer housing. It is
possible however, to engineer the incoming MV circuit breaker, isolator or
ring main unit (RMU) as part of a packaged substation installation.
A full inter-tripping facility between MV and LV circuit breakers as well
as interlocking between transformer housing and MV breaker is available
to meet specific requirements.
Standard forms of instrumentation, measuring and protective circuitry
can be provided, the latter including alarm indication and trip relay
protection for the transformer windings.
Impulse voltage requirements for the supply system can readily be met by
the provision of surge diverters at the MV terminals of the transformer.
Due to the number of variations possible when putting together a
composite package each substation is the subject of an individual design
exercise, aimed at producing the optimum arrangement for the particular
installation under consideration.
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