Title of Invention	A NOVEL RADIALLY VENTED INTERRUPTER FOR GAS CIRCUIT BREAKER APPLICATION
Abstract	This invention relates to a radially vented interrupter for high voltage high power gas circuit breaker, comprising; a compression volume (01) which allows storage of cold gas for compression including collection of fresh gas during closing operation; an expansion volume (02) which allows a direct exposure of the available gas during the arcing; an intermediate volume (03) where stored gas is allowed to be compressed by the gas from the expansion volume (02) thereby raising the gas pressure during the arcing period due to compression by the gas from the expansion volume (02) including mixing of the gasses, the compression volume (01), the expansion volume (02), and the intermediate volume (03) being strategically coupled to each other; a main chamber (05) receiving beyond a particular point of time the gas flow from the expansion volume (02) via multiple control outlets (06,07,08). A radial outlet (09) for shortening the length of the exit channel of one (07) of the multiple control outlets (6,7,8) which optimizes the electrical circuit and the flow passages for the arcing products to achieve an improved total venting rate at interruption.

Title of Invention

A NOVEL RADIALLY VENTED INTERRUPTER FOR GAS CIRCUIT BREAKER APPLICATION

Abstract

This invention relates to a radially vented interrupter for high voltage high power gas circuit breaker, comprising; a compression volume (01) which allows storage of cold gas for compression including collection of fresh gas during closing operation; an expansion volume (02) which allows a direct exposure of the available gas during the arcing; an intermediate volume (03) where stored gas is allowed to be compressed by the gas from the expansion volume (02) thereby raising the gas pressure during the arcing period due to compression by the gas from the expansion volume (02) including mixing of the gasses, the compression volume (01), the expansion volume (02), and the intermediate volume (03) being strategically coupled to each other; a main chamber (05) receiving beyond a particular point of time the gas flow from the expansion volume (02) via multiple control outlets (06,07,08). A radial outlet (09) for shortening the length of the exit channel of one (07) of the multiple control outlets (6,7,8) which optimizes the electrical circuit and the flow passages for the arcing products to achieve an improved total venting rate at interruption.

Full Text	FIELD OF THE INVENTION The invention generally relates to gas circuit breakers. More particularly, the invention relates to a radially vented interrupter for high voltage, high power gas circuit breaker. BACKGROUND OF THE INVENTION A Circuit Breaker (CB) is primarily used to interrupt normal / fault / capacitive / inductive currents of high voltage installations. When the CB is in closed condition it allows conduction of electrical charge (current) through in a closed electrical system (circuit) depending on the system characteristics and conditions. When fault current is interrupted by a circuit breaker, arc is struck between the arcing contacts. The energy content of the arc depends on the current magnitude, length of the arc and similar other parameters. As the temperatures of the arc are quite high it decomposes the insulating medium and materials exposed to arc. Byproducts of the chemical reaction at elevated temperature also accumulate in the vicinity and shall be removed for sustaining the dielectric properties of the inter-electrode gap on interruption. In conventional gas circuit breakers, the arc products are vented through annular axial passages of fixed and moving parts of the interrupter. For large dimensions and operating strokes of the high voltage and high power interrupters the venting passages are long, hampering venting process. To achieve desired interrupter performance excess quantity of gas and higher differential pressures are used in conventional gas interrupters as on date. Three channels are mostly provided in conventional gas interrupters for venting the arc products: 1. Throat of top arcing contact (fixed / movable) 2. Throat of bottom / movable arcing contact and 3. Time varying annular gap between top arcing contact (fixed / movable) and nozzle. The conductance of the flow channels, being proportional to its cross-section is limited by the length of the flow channel. The high impressed voltage demand higher dielectric clearances between the live connections of an interrupter. The length of the interrupter is divided in three section of two electrodes (fixed, moving) and the inter electrode gap. While inter electrode gap is minimal most of the interrupter length is divided in two electrode assemblies. The length of flow channel, at least for the moving contact assembly, is almost half of the interrupter length. For this constraint the arc product mostly is carried by top vent in mono flow interrupters while the situation is improved in dual flow interrupters. However, for this reason, none of the interrupters utilizes full capabilities of the flow channels. OBJECTS OF THE INVENTION It is therefore an object of the invention to propose a radially vented interrupter for high voltage, high power gas circuit breaker, which eliminates the disadvantages of the prior art. Another object of the invention is to propose a radially vented interrupter for high voltage, high power gas circuit breaker, which exhibits improved current interruption capabilities. A still another object of the invention is to propose a radially vented interrupter for high voltage, high power gas circuit breaker, which achieves an efficient total venting rate at interruption. Yet another object of the invention is to propose a radially vented interrupter for high voltage, high power gas circuit breaker, which achieves an improved mass flow rate around current zero. A further object of the invention is to propose a radially vented interrupter for high voltage, high power gas circuit breaker, which ensures clearance of arc products in time. SUMMARY OF THE INVENTION Accordingly, there is provided a radially vented interrupter for high voltage high power gas circuit breaker, comprising; a compression volume which allows storage of cold gas for compression including collection of fresh gas during closing operation; an expansion volume which allows a direct exposure of the available gas during the arcing; an intermediate volume where stored gas is allowed to be compressed by the gas from the expansion volume thereby raising the gas pressure during the arcing period due to compression by the gas from the expansion volume including mixing of the gasses, the compression volume, the expansion volume, and the intermediate volume being strategically coupled to each other; a main chamber receiving beyond a particular point of time the gas flow from the expansion volume via multiple control outlets. A radial outlet for shortening the length of the exit channel of one of the multiple control outlets which optimizes the electrical circuit and the flow passages for the arcing products to achieve an improved total venting rate at interruption. Thus, the invention incorporates a radial exit close to inter-electrode gap, and optimizes the gas passage area between (a). intermediate and expansion volume (b). compression and intermediate volume for directing cold gas in either direction of inter-electrode gap as per required proportion. An optional Cushion volume for controlling the interrupting performance and damping characteristics is provided. One or multiple exits are arranged to control total conductance. An improved mass flow rate at interruption is provided to improve insulation recovery by regulating gas flow from the compression volume to inter-electrode gap by controlling various parameters such as: (a). Time instant at which the expansion volume pressure and intermediate volume pressures become equal. (b). Time instant at which the compression volume pressure exceeds intermediate volume pressure. (c). Difference of the compression and the intermediate volume pressures. The invented interrupter is of reduced size. BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS The invention is described with the help of Figures 1 to 4, where: Figure 1: Shows the conventional interrupter. Figure 2: Shows the principle concept of two-stage blast interrupter. Figure 3: Shows details of a radial outlet for the two-stage blast according to the invention. Figure 4: Shows a two-stage blast interrupter with radial exit according to the invention. DETAIL DESCRIPTION OF THE INVENTION As shown in figure 4, the inventive, two-stage blast interrupter, comprises three strategically coupled volumes. The aim of this arrangement is to achieve efficient current interruption. The first volume is the compression volume (01), where a piston-cylinder arrangement allows storage of cold gas and its compression during interruption by movement of a piston (14) conventionally coupled to the operating mechanism/drive. The fresh gas is collected and retained in the compression volume (01) during closing operation. The second one is an expansion volume (02), where the available gas is directly exposed to the arc (13) during contact separation/ arcing. The third one is an intermediate volume (03), where stored gas is compressed by the expansion volume gas (02) and gas pressure rises during arcing period due to compression, by the expansion volume (02) gas, and mixing (refer Fig. 2). Inventers have earlier proposed a conditional gating device, a non-returnable flap valve [04], between the compression volume and intermediate volume vide the Indian patent application No. 1694/Kol/2007, which is incorporated herein by way of reference. The valve allows gas flow from the compression volume (01) to the intermediate volume (03) only when the pressure (Pc) of the compression volume (01) is greater than the pressure (Pj) of the intermediate volume (03). The gating device (a flap valve) is positioned between the intermediate (03) and compression volume (01). In the present two-stage blast interrupter, beyond a particular point of time, the movement of the nozzle (12) allow the gas to flow from the expansion volume (02) to a main chamber (05). During arcing period, in the interrupter the gas flows from the expansion (02) to the main chamber (05) through multiple controlled outlets. First one of the multiple controlled outlets is a throat fixed / movable contact (06). Second one is a throat of movable contact (07). The third one is an annular gap (08) between the fixed/movable contact (06) and the nozzle (12). According to the invention, a radial outlet (09) is introduced, shortening the length of the exit channel in the moving contact (07) of the interrupter. More clearly, the radial vent (09) opens in to the annular cavity of the moving arcing contact (07) (refer Fig. 3). This modification optimizes the electrical circuit and the flow passages for the arcing products. The aim of the arrangement is to achieve efficient total venting rate at interruption. For a particular fixed/movable contact passages, the improved flow conductance of the moving contact greatly improves the interrupter performance both in terms of short circuit capabilities and dielectric recovery. The inventive configuration allows the cold gas to be directed in either direction of inter-electrode gap in required proportion. In arcing phase, the pressure build-up in the expansion volume (02) is relatively high. The pressure difference generates proportionate mass flow which is improved for the presently proposed radially vented interrupter. Around the current zero, in the proposed interrupter, cold gas from the compression volume (01) can be transferred to sweep all ionized material in the arc column with improved window time. A Cushion volume [10] is arranged for controlling the pressure of the compression volume (01) and indirectly the interrupting capability of the device. This additional volume (10) avoids over pressure and slows down at end of stroke and over-damping. Thus, by using the invented two-stage blast interrupter with radial vent, significant improvement in mass flow rate around current zero can be achieved, which supports effective interruption of current. The mass flow rate at interruption in the proposed interrupter is further controlled by the following parameters in the invention: 1. Time instant at which the pressure of the expansion volume (02) and that of the intermediate volume (03) become equal. 2. Time instant at which the pressure of the compression volume (01) exceeds that of the intermediate volume (03). 3. Difference of pressures of the compression and intermediate volume (01, 03). The novelty of the proposed configuration is the availability of a vent close to the inter-electrode gap, ensuring clearance of arc products well in time. The shortening of the length of the exit channel helps in improving conductance and enhances discharge / discharge rate. The recovery of the medium in GCB is proportional to the pace at which the hot gas is evacuated from inter-electrode gap and fresh gas is replenished. WE CLAIM 1. A radially vented interrupter for high voltage high power gas circuit breaker, comprising: - a compression volume (01) which allows storage of cold gas for compression including collection of fresh gas during closing operation; - an expansion volume (02) which allows a direct exposure of the available gas during the arcing; - an intermediate volume (03) where stored gas is allowed to be compressed by the gas from the expansion volume (02) thereby raising the gas pressure during the arcing period due to compression by the gas from the expansion volume (02) including mixing of the gasses, the compression volume (01), the expansion volume (02), and the intermediate volume (03) being strategically coupled to each other; - a main chamber (05) receiving beyond a particular point of time the gas flow from the expansion volume (02) via multiple control outlets (06,07,08), characterized by comprising; - a radial outlet (09) for shortening the length of the exit channel of one (07) of the multiple control outlets (6,7,8) which optimizes the electrical circuit and the flow passages for the arcing products to achieve an improved total venting rate at interruption. 2. A radially vented interrupter as claimed in claim 1, wherein the multiple outlets (06,07,08) comprises a throat fixed/movable contact (06), a throat of movable contact (07), and an annular gap (08) between the fixed/movable contact and the nozzle (12). 3. A radially vented interrupter as claimed in claim 1, comprising a cushion volume (10) for controlling the pressure of the compression volume (01) 4. A radially vented interrupter as claimed in claim 1, wherein mass flow rate at the interruption is further controlled based on the parametric relationships of: - a time instant at which the pressure of the expansion volume (02) and that of the intermediate volume (03) becomes equal; - a time instant at which the pressure of the compression volume (01) exceeds that of the intermediate volume (03), and - difference in pressure of the compression and intermediate volumes (01,03) 5. A radially vented interrupter for high voltage high power gas circuit breaker, as substantially described and illustrated herein with reference to the accompanying drawings. This invention relates to a radially vented interrupter for high voltage high power gas circuit breaker, comprising; a compression volume (01) which allows storage of cold gas for compression including collection of fresh gas during closing operation; an expansion volume (02) which allows a direct exposure of the available gas during the arcing; an intermediate volume (03) where stored gas is allowed to be compressed by the gas from the expansion volume (02) thereby raising the gas pressure during the arcing period due to compression by the gas from the expansion volume (02) including mixing of the gasses, the compression volume (01), the expansion volume (02), and the intermediate volume (03) being strategically coupled to each other; a main chamber (05) receiving beyond a particular point of time the gas flow from the expansion volume (02) via multiple control outlets (06,07,08). A radial outlet (09) for shortening the length of the exit channel of one (07) of the multiple control outlets (6,7,8) which optimizes the electrical circuit and the flow passages for the arcing products to achieve an improved total venting rate at interruption.

Full Text

FIELD OF THE INVENTION
The invention generally relates to gas circuit breakers. More particularly, the
invention relates to a radially vented interrupter for high voltage, high power gas
circuit breaker.
BACKGROUND OF THE INVENTION
A Circuit Breaker (CB) is primarily used to interrupt normal / fault / capacitive /
inductive currents of high voltage installations. When the CB is in closed
condition it allows conduction of electrical charge (current) through in a closed
electrical system (circuit) depending on the system characteristics and
conditions.
When fault current is interrupted by a circuit breaker, arc is struck between the
arcing contacts. The energy content of the arc depends on the current
magnitude, length of the arc and similar other parameters. As the temperatures
of the arc are quite high it decomposes the insulating medium and materials
exposed to arc. Byproducts of the chemical reaction at elevated temperature also
accumulate in the vicinity and shall be removed for sustaining the dielectric
properties of the inter-electrode gap on interruption. In conventional gas circuit
breakers, the arc products are vented through annular axial passages of fixed
and moving parts of the interrupter. For large dimensions and operating strokes

of the high voltage and high power interrupters the venting passages are long,
hampering venting process. To achieve desired interrupter performance excess
quantity of gas and higher differential pressures are used in conventional gas
interrupters as on date.
Three channels are mostly provided in conventional gas interrupters for venting
the arc products:
1. Throat of top arcing contact (fixed / movable)
2. Throat of bottom / movable arcing contact and
3. Time varying annular gap between top arcing contact (fixed / movable) and
nozzle.
The conductance of the flow channels, being proportional to its cross-section is
limited by the length of the flow channel. The high impressed voltage demand
higher dielectric clearances between the live connections of an interrupter. The
length of the interrupter is divided in three section of two electrodes (fixed,
moving) and the inter electrode gap. While inter electrode gap is minimal most
of the interrupter length is divided in two electrode assemblies. The length of
flow channel, at least for the moving contact assembly, is almost half of the
interrupter length. For this constraint the arc product mostly is carried by top
vent in mono flow interrupters while the situation is improved in dual flow
interrupters. However, for this reason, none of the interrupters utilizes full
capabilities of the flow channels.

OBJECTS OF THE INVENTION
It is therefore an object of the invention to propose a radially vented interrupter
for high voltage, high power gas circuit breaker, which eliminates the
disadvantages of the prior art.
Another object of the invention is to propose a radially vented interrupter for
high voltage, high power gas circuit breaker, which exhibits improved current
interruption capabilities.
A still another object of the invention is to propose a radially vented interrupter
for high voltage, high power gas circuit breaker, which achieves an efficient total
venting rate at interruption.
Yet another object of the invention is to propose a radially vented interrupter for
high voltage, high power gas circuit breaker, which achieves an improved mass
flow rate around current zero.
A further object of the invention is to propose a radially vented interrupter for
high voltage, high power gas circuit breaker, which ensures clearance of arc
products in time.
SUMMARY OF THE INVENTION
Accordingly, there is provided a radially vented interrupter for high voltage high
power gas circuit breaker, comprising; a compression volume which allows

storage of cold gas for compression including collection of fresh gas during
closing operation; an expansion volume which allows a direct exposure of the
available gas during the arcing; an intermediate volume where stored gas is
allowed to be compressed by the gas from the expansion volume thereby raising
the gas pressure during the arcing period due to compression by the gas from
the expansion volume including mixing of the gasses, the compression volume,
the expansion volume, and the intermediate volume being strategically coupled
to each other; a main chamber receiving beyond a particular point of time the
gas flow from the expansion volume via multiple control outlets. A radial outlet
for shortening the length of the exit channel of one of the multiple control outlets
which optimizes the electrical circuit and the flow passages for the arcing
products to achieve an improved total venting rate at interruption.
Thus, the invention incorporates a radial exit close to inter-electrode gap, and
optimizes the gas passage area between
(a). intermediate and expansion volume
(b). compression and intermediate volume
for directing cold gas in either direction of inter-electrode gap as per required
proportion.
An optional Cushion volume for controlling the interrupting performance and
damping characteristics is provided.

One or multiple exits are arranged to control total conductance. An improved
mass flow rate at interruption is provided to improve insulation recovery by
regulating gas flow from the compression volume to inter-electrode gap by
controlling various parameters such as:
(a). Time instant at which the expansion volume pressure and
intermediate volume pressures become equal.
(b). Time instant at which the compression volume pressure exceeds
intermediate volume pressure.
(c). Difference of the compression and the intermediate volume
pressures.
The invented interrupter is of reduced size.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The invention is described with the help of Figures 1 to 4, where:
Figure 1: Shows the conventional interrupter.
Figure 2: Shows the principle concept of two-stage blast interrupter.

Figure 3: Shows details of a radial outlet for the two-stage blast according to the
invention.
Figure 4: Shows a two-stage blast interrupter with radial exit according to the
invention.
DETAIL DESCRIPTION OF THE INVENTION
As shown in figure 4, the inventive, two-stage blast interrupter, comprises three
strategically coupled volumes. The aim of this arrangement is to achieve efficient
current interruption. The first volume is the compression volume (01), where a
piston-cylinder arrangement allows storage of cold gas and its compression
during interruption by movement of a piston (14) conventionally coupled to the
operating mechanism/drive. The fresh gas is collected and retained in the
compression volume (01) during closing operation. The second one is an
expansion volume (02), where the available gas is directly exposed to the arc
(13) during contact separation/ arcing. The third one is an intermediate volume
(03), where stored gas is compressed by the expansion volume gas (02) and gas
pressure rises during arcing period due to compression, by the expansion volume
(02) gas, and mixing (refer Fig. 2). Inventers have earlier proposed a conditional
gating device, a non-returnable flap valve [04], between the compression volume
and intermediate volume vide the Indian patent application No. 1694/Kol/2007,
which is incorporated herein by way of reference. The valve allows gas flow from
the compression volume (01) to the intermediate volume (03) only when the
pressure (Pc) of the compression volume (01) is greater than the pressure (Pj) of

the intermediate volume (03). The gating device (a flap valve) is positioned
between the intermediate (03) and compression volume (01).
In the present two-stage blast interrupter, beyond a particular point of time, the
movement of the nozzle (12) allow the gas to flow from the expansion volume
(02) to a main chamber (05). During arcing period, in the interrupter the gas
flows from the expansion (02) to the main chamber (05) through multiple
controlled outlets. First one of the multiple controlled outlets is a throat fixed /
movable contact (06). Second one is a throat of movable contact (07). The third
one is an annular gap (08) between the fixed/movable contact (06) and the
nozzle (12).
According to the invention, a radial outlet (09) is introduced, shortening the
length of the exit channel in the moving contact (07) of the interrupter. More
clearly, the radial vent (09) opens in to the annular cavity of the moving arcing
contact (07) (refer Fig. 3). This modification optimizes the electrical circuit and
the flow passages for the arcing products. The aim of the arrangement is to
achieve efficient total venting rate at interruption. For a particular fixed/movable
contact passages, the improved flow conductance of the moving contact greatly
improves the interrupter performance both in terms of short circuit capabilities
and dielectric recovery. The inventive configuration allows the cold gas to be
directed in either direction of inter-electrode gap in required proportion. In arcing
phase, the pressure build-up in the expansion volume (02) is relatively high. The
pressure difference generates proportionate mass flow which is improved for the

presently proposed radially vented interrupter. Around the current zero, in the
proposed interrupter, cold gas from the compression volume (01) can be
transferred to sweep all ionized material in the arc column with improved window
time. A Cushion volume [10] is arranged for controlling the pressure of the
compression volume (01) and indirectly the interrupting capability of the device.
This additional volume (10) avoids over pressure and slows down at end of
stroke and over-damping. Thus, by using the invented two-stage blast
interrupter with radial vent, significant improvement in mass flow rate around
current zero can be achieved, which supports effective interruption of current.
The mass flow rate at interruption in the proposed interrupter is further
controlled by the following parameters in the invention:
1. Time instant at which the pressure of the expansion volume (02) and that
of the intermediate volume (03) become equal.
2. Time instant at which the pressure of the compression volume (01)
exceeds that of the intermediate volume (03).
3. Difference of pressures of the compression and intermediate volume (01,
03).
The novelty of the proposed configuration is the availability of a vent close to the
inter-electrode gap, ensuring clearance of arc products well in time. The

shortening of the length of the exit channel helps in improving conductance and
enhances discharge / discharge rate. The recovery of the medium in GCB is
proportional to the pace at which the hot gas is evacuated from inter-electrode
gap and fresh gas is replenished.

WE CLAIM
1. A radially vented interrupter for high voltage high power gas circuit
breaker, comprising:
- a compression volume (01) which allows storage of cold gas for
compression including collection of fresh gas during closing
operation;
- an expansion volume (02) which allows a direct exposure of the
available gas during the arcing;
- an intermediate volume (03) where stored gas is allowed to be
compressed by the gas from the expansion volume (02) thereby
raising the gas pressure during the arcing period due to
compression by the gas from the expansion volume (02) including
mixing of the gasses, the compression volume (01), the expansion
volume (02), and the intermediate volume (03) being strategically
coupled to each other;
- a main chamber (05) receiving beyond a particular point of time
the gas flow from the expansion volume (02) via multiple control
outlets (06,07,08), characterized by comprising;

- a radial outlet (09) for shortening the length of the exit channel of
one (07) of the multiple control outlets (6,7,8) which optimizes the
electrical circuit and the flow passages for the arcing products to
achieve an improved total venting rate at interruption.
2. A radially vented interrupter as claimed in claim 1, wherein the multiple
outlets (06,07,08) comprises a throat fixed/movable contact (06), a throat
of movable contact (07), and an annular gap (08) between the
fixed/movable contact and the nozzle (12).
3. A radially vented interrupter as claimed in claim 1, comprising a cushion
volume (10) for controlling the pressure of the compression volume (01)
4. A radially vented interrupter as claimed in claim 1, wherein mass flow rate
at the interruption is further controlled based on the parametric
relationships of:
- a time instant at which the pressure of the expansion volume (02)
and that of the intermediate volume (03) becomes equal;
- a time instant at which the pressure of the compression volume
(01) exceeds that of the intermediate volume (03), and
- difference in pressure of the compression and intermediate
volumes (01,03)

5. A radially vented interrupter for high voltage high power gas circuit
breaker, as substantially described and illustrated herein with reference to
the accompanying drawings.

This invention relates to a radially vented interrupter for high voltage high power
gas circuit breaker, comprising; a compression volume (01) which allows storage of cold gas for compression including collection of fresh gas during closing operation; an expansion volume (02) which allows a direct exposure of the
available gas during the arcing; an intermediate volume (03) where stored gas is allowed to be compressed by the gas from the expansion volume (02) thereby raising the gas pressure during the arcing period due to compression by the gas
from the expansion volume (02) including mixing of the gasses, the compression volume (01), the expansion volume (02), and the intermediate volume (03) being strategically coupled to each other; a main chamber (05) receiving beyond
a particular point of time the gas flow from the expansion volume (02) via multiple control outlets (06,07,08). A radial outlet (09) for shortening the length of the exit channel of one (07) of the multiple control outlets (6,7,8) which optimizes the electrical circuit and the flow passages for the arcing products to
achieve an improved total venting rate at interruption.

Documents:

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Patent Number

268234

Indian Patent Application Number

772/KOL/2008

PG Journal Number

35/2015

Publication Date

28-Aug-2015

Grant Date

21-Aug-2015

Date of Filing

25-Apr-2008

Name of Patentee

BHARAT HEAVY ELECTRICALS LIMITED

Applicant Address

REGIONAL OPERATIONS DIVISION (ROD), PLOT NO : 9/1, DJBLOCK 3RD FLOOR, KARUNAMOYEE, SALT LAKE CITY, KOLKATA - 700091, HAVING ITS REGISTERED OFFICE AT BHEL HOUSE, SIRI FORT, NEW DELHI – 110049

Inventors:

#	Inventor's Name	Inventor's Address
1	DR. MANDAVA MOHANA RAO	NOT AVAILABLE
2	DR. HARI SHANKAR JAIN	NOT AVAILABLE

PCT International Classification Number

H01H33/80; H01H33/70

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA