Fuse Cannisters
Load-break
Dead-break
Fuse Cannisters
TPL 44-837, May 2000, Page 1 of 4
Current Limiting Fuse Cannisters, Load-break
and Dead-break Designs
General Information and Ratings
ABB Power T&D Company Inc.
ABB
General Description
Dead-break Cannister
Lower Contact Assembly
The Drywell Current Limiting Fuse Cannister is a removable
fuse assembly for use in single and three phase pad-mounted
transformers. The fuse well assembly accepts general purpose
current limiting fuses and is available in both load-break and
dead-break designs. The combination of the drywell current
limiting fuse cannister and the general purpose current limiting
fuse provides a reliable, versatile and easily serviced current
limiting protection system for transformers.
Features and Advantages
Test Proven Quality and Reliability
The ABB Fuse Cannister has passed a series of design tests
which offer verification of the design reliability. The tests are
covered in TD 44-817 and are listed below:
1. Switching Test
2. Fault Close Test
3. Dielectric Test
4. Short Time Current Test
5. Temperature Thermocycle Test
6. Safe Transit Test
In addition to the design testing, the following production tests
are done:
1: Audit - Dimension check to verify critical dimensions.
2. 100% - Seal test to verify sealing integrity.
Current Limiting Capability
The Drywell Current Limiting Fuse Cannister will accept general
purpose current limiting fuses of the CX/NX, ELX and GP
variety. The current limiting fuse provides instantaneous
Load-break Cannister
Lower Contact Assembly
protection for the system and transformer from faults within
the interrupting rating of the fuse. Current limiting fuses offer
faster response times and higher interrupting ratings than
expulsion type fuses.
Load-break Design
The Load-break Current Limiting Fuse Cannister has an arc
quenching device inside the cannister to permit load-break
switching operations. The load make/load break capability
of the fuse cannister provides the additional versatility and
economy of load switching at the fuse itself without the need
for additional switches.
Dead-break Design
The dead-break design does not have arc stretching and
quenching capability. If a transformer already has a high
voltage switch, the dead-break design offers an economical
method of providing current limiting fuse protection. The deadbreak design offers all the features of the load-break design
except for the loadmake/loadbreak and fault close capability.
Drawout Assembly
The current limiting fuse is removed from the cannister at the
front of the transformer using a standard hot stick. Once
removed, the fuse can be inspected and/or replaced as
necessary without disturbing the seal integrity of the
transformer.
Straight or Slant Mounting
The ABB fuse cannister is available in both straight and slant
mounting designs. The slant mounting is especially suited
to single phase pad-mount transformer where the slanted
design permits for shorter tank depth and a lower profile design.
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Rugged Fuse Assembly
The cannister is made up of two basic parts: the fuse cannister
body assembly and the draw out assembly. All of the
insulating parts are glass reinforced thermoset materials
which are both arc and track resistant.
The cannister body is assembled from glass wound epoxy
tubing and a molded thermoset epoxy housing with brass
electrical contacts. The upper draw out assembly is made
from molded thermoset polyester and stainless steel hook
eye and end cap.
High Strength Contact Structure
The fuse cannister contacts are brass to copper at the bushing
lead connection and copper to brass at the cannister to
winding connection. The combination of brass and copper
provides the necessary conductivity and high strength for the
internal lead connections. A spiral spring contact made of a
silver plated copper alloy is used at the winding connection
contact to insure consistent contact surface and balanced
contact pressure. The contact to cannister interface is
uniquely designed to provide transformer access to the
contacts and yet maintain the seal integrity of the cannister.
High Current Withstand
Both the load-break and dead-break fuse cannisters are
designed to withstand a 10 cycle, 60Hz current of 10,000
amperes without damage to the cannister or contact structure.
This design ensures that both the cannister and contact
structure will withstand high current surges without impairing
the cannister’s ability to meet its functional requirements.
Accessories
End Cap Cover
The end cap cover (451B806G02) is used to insulate the lower
lead clamp and end cap assembly of the fuse cannister. The
end cap cover is made from a black thermo-plastic polyester,
and is designed to fit over the cannister end cap and lead
clamp assembly. The end cap is supplied as standard
equipment on load-break fuse cannisters. The end cap is not
provided with dead-break fuse cannisters and must be ordered
separately.
Mounting Flange
The mounting flange comes in two configurations; straight
(5995A52G01), and slant.(5995A53G01). Both flanges are
made from zinc plated steel with a yellow chromate sealer.
On standard fuse cannisters, the mounting flange is supplied
with the cannister as part of the mounting hardware.
Page 3 of 4
Load-break Cannister
Cutaway View
To Order - Specify Style N umber
C anni ster
Fuse
Type
Type
kV
Mounti ng
BIL (kV) C onti nuous Short Ti me
Arrangement
C urrent
(Amperes)
60 Hz
#
Style
C urrent
Wi thstand
Load-make/
Number
(1.3
Voltage
Load-break
asymmetry
(kV)
Operati ons
Factor i n
at 200
Amperes)
Amperes
D ead-break
C X/NX
8.3
Strai ght
95
200
10,000
34
N/A
608C 617G22
D ead-break
C X/NX
8.3
Slant
95
200
10,000
34
N/A
608C 617G24
D ead-break
C X/NX
15
Strai ght
125
200
10,000
40
N/A
608C 617G51
D ead-break
C X/NX
15
Slant
125
200
10,000
40
N/A
608C 617G53
D ead-break
C X/NX
23
Strai ght
150
200
10,000
50
N/A
608C 617G35
D ead-break
C X/NX
23
Slant
150
200
10,000
50
N/A
608C 617G36
Load-break
C X/NX
8.3
Strai ght
95
200
10,000
34
10
608C 433G11
Load-break
C X/NX
8.3
Slant
95
200
10,000
34
10
608C 433G12
Load-break
C X/NX
15
Strai ght
125
200
10,000
40
10
608C 433G43
Load-break
C X/NX
15
Slant
125
200
10,000
40
10
608C 433G44
Tank Gasket
Two different tank gaskets are available depending upon the
type of cannister installation. Both the straight (5994A60H01)
and slant (5994A60H02) mounting gasket are made from
Nitrile®. The tank gasket is supplied with the hardware kit
on all standard fuse cannisters.
Garter Spring
The contact garter springs (51D0562H07) are designed to
provide electrical conductivity between the upper corona shield
and the upper lead contact assembly and as a field shaper
between the upper corona shield and tank wall. The spring
is made from stainless steel and is provided as standard
equipment on the fuse cannisters listed above. See DS 44887 page 14 for garter spring installation instructions.
Lead Clamp & Hardware
The upper and lower contact clamps are identical. They are
made from tin plated steel to resist corrosion during transport
and storage before assembly in the transformer. All standard
fuse cannisters are provided with two lead clamp assemblies
and the necessary mounting nuts, bolts, and washers. See
DS 44-887 pg. 12 (straight) or pg. 13 (slant) for ordering
information.
ABB
ABB Power T&D Company Inc.
1128 Highway 412 S.
Alamo, TN 38001-3813
TPL 44-837
May 2000
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