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The MOLE™ and HYCRAB™
The most popular of the engineered connec-
tors developed specifically for underground
manholes and transformer vaults are the
MOLE™ and the HYCRAB™ that provide for
multiple connections at a single junction
point of main, feeder, and service cables.
Pre-insulated to eliminate extensive taping,
these connectors are essentially bus bars
with several cable outlets: mechanical instal-
lation in the MOLE™, and compression
installation in the HYCRAB™.
Limiters and Fuses
To prevent “roasting” of cable insulation,
resulting from fault current, BURNDY
®
has
developed cable limiters that are inserted in
each secondary cable at all junction points.
Network protector fuses have been designed
to back up the protector breaker in the event
of a malfunction during a transformer or pri-
mary cable fault. By coordinating the time cur-
rent characteristics of the fuse with those of
the cable limiters, the possibility of limiter
blowing on primary faults is eliminated, which
in turn reduces the fault finding task. Also, lim-
iter, fuse, and cable insulation characteristics
must be carefully coordinated to assure isolat-
ing a fault on the secondary before it can
cause extensive damage or interrupt service
in other sections of the secondary system.
High Capacity Limiter 200,000 Amperes
at 600 Volts
The BURNDY
®
High Capacity Limiter is
designed to economically protect electrical
distribution systems from the destructive
effect of high energy faults. The increasing
number of 600 volt secondary network instal-
lations for industrial and commercial applica-
tions demand a cable limiter that can safely
interrupt 200,000 amperes (symmetrical
available) and one that will also completely
coordinate with the higher voltage nework
protector fuses.
Available fault currents as high as 200,000
amperes rms at 600 volts across the fusible
elements have been interrupted during tests
on the BURNDY
®
High Capacity Limiter.
The power factor during these tests was
less than 15%, thereby imposing the most
difficult clearing conditions. No external dis-
trubance is experienced upon clearing fault
currents from the “float” value to 200,000
amperes. The quartz filler absorbs the
intense energy generated by interrupting
the fault current. The quartz fuses into tubu-
lar fulgurites, with a high dielectric strength,
and forms an insulating barrier between the
melted link sections. This action prevents
restrike of the internal arc. The rugged glass
melamine housing provides a vessel that
completely contains the developed energy.
The carefully developed time-current charac-
teristics and rigid manufacturing tolerances
assure proper coordination with the network
protector fuses and the insulation damage
characteristics of 4/0, 250, 350, 500 and 750
kcmil cable.
The High Capacity Limiter is available in four
variations to accommodate a variety of
installation practices. The Type HYS has
cable sockets at both ends, which allow for
indenting to the cable ends with a hydraulic
BURNDY
®
HYPRESS™. The HYAO has an
offset lug on one end which permits back-to-
back mounting on bus bar.
For those installations where BURNDY
®
MOLEs™ are used for manhole junctions or
transformer vault buses, the Type HYM per-
mits a replaceable connection of the limiter
directly to the MOLE outlet at one end and
a compression cable connection at the
other.
Modern electrical distribution systems
require low cost protection to safeguard
costly equipment and quickly isolate faults,
so that the undamaged portions of the sys-
tem may function normally. BURNDY
®
High
Capacity Limiters assure positive, economi-
cal protection when installed in properly
designed systems.
Compression Connectors
BURNDY
®
HYDENT™ compression type
connectors, and installation tools, have been
designed for splicing and terminating copper
as well as aluminum underground cables, in
both primary and secondary circuits.
BURNDY
®
tools and dies are custom
designed to produce sound electrical, and
mechanical joints on BURNDY
®
connectors.
The use of BURNDY’s matched tools and
connectors assures optimum results.
Residential Underground
The trend toward improvement in neighbor-
hood appearances, and the elimination of
storm outages, tree trimming, etc., has creat-
ed the need for residential underground
distribution. To meet these needs, BURNDY
®
offers: Mechanical type pre-insulated multi-
conductor terminal connectors for sub-
mersible transformer locations; and compact
multiconductor connectors for above ground
transformer and enclosures. For service
taps, BURNDY
®
offers: Pre-insulated, multi-
conductor compression and mechanical
connectors; and a range taking compression
connector for below grade service. Power
pedestals for direct burial, above ground
application, and conduit systems are offered.
Residential Underground Fuse Block assem-
bly with replaceable fuse for each service
cable is also available.
TYPES OF BURNDY
®
UNDERGROUND CONNECTORS
AND ACCESSORIES
K-4
Blue highlighted items are industry standard and most frequently ordered.
Canada: 1-800-387-6487
www.burndy.com
US: 1-800-346-4175
Underground
BURNDY
®