The present disclosure relates to the field of ring main unit (RMU).
More particularly the present disclosure related to a test bushing for the RMU.
BACKGROUND
[0002] Background description includes information that may be useful in
understanding the present invention. It is not an admission that any of the
information provided herein is prior art or relevant to the presently claimed
invention, or that any publication specifically or implicitly referenced is prior art.
[0003] Ring main units are used for power distribution and transmission.
Ring main units are very much used for reducing down time and can be connected in densely populated area through underground cables. In case there is any fault in the underground cables, then a test bushing is used to identify location of the fault and then the cable can be dug at the identified location and can be rectified. The conventional test bushing includes straight conductors for facilitating test inputs to the underground cables. The test bushings occupies a considerable space inside the RMU and are difficult to effectively stack, in lesser space, with elements inside the RMU since the test bushing are not made according to element's orientation inside the RMU.
[0004] There is, therefore, a need of an improved test bushing design that
can be area efficient when configured inside the RMU and is compact in size.
OBJECTS OF THE PRESENT DISCLOSURE
[0005] Some of the objects of the present disclosure, which at least one
embodiment herein satisfies are as listed herein below.
[0006] It is an object of the present disclosure to provide a test bushing
that is compact.
[0007] It is an object of the present disclosure to provide a test bushing
that is economical.
[0008] It is an object of the present disclosure to provide a test bushing
that is designed according to element's orientation inside the RMU.

[0009] It is an object of the present disclosure to provide a test bushing
that can be effectively stacked inside the RMU.
[0010] It is an object of the present disclosure to provide a test bushing
that can be easy to handle & assemble.
SUMMARY
[0011] The present disclosure relates to the field of ring main unit (RMU).
More particularly the present disclosure related to a test bushing for the RMU.
[0012] An aspect of the present disclosure pertains to a bushing adapted to
be configured with a ring main unit (RMU). The bushing includes a housing having a front portion which remain outside the tank, and a rear portion that remain inside the tank and configured at an end of the front portion. A longitudinal axis of the front portion is configured at a pre-defined angle with a longitudinal axis of the rear portion. An input port configured inside the front portion; and an output port configured inside the rear portion, and the output port is electrically configured with the input port through one or more conductors, wherein the one or more conductors comprises one or more bends facilitating compact size of the bushing.
[0013] In an aspect, the one or more bends may be positioned to ensure a
minimum distance between adjacent conductors of the one or more conductors.
The bushing may be mounted along with O-ring by placing the bushing inside an
SF6 tank of the RMU. The bushing may be configured to test and locate fault in
underground cables electrically connected to the RMU. Bushing may be adapted
to be configured on an outer surface of the RMU. The input port may include one
or more first ends of the one or more conductors, and the one or more ends are
covered with epoxy facilitating formation of a cone like structure over the one or
more first ends for insulator boot mounting. The output port may comprise one or
more second ends of the one or more conductors, and the one or more second ends
may be configured to input the test input supply to the underground cables.
[0014] Various objects, features, aspects and advantages of the inventive
subject matter will become more apparent from the following detailed description

of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.
BRIEF DESCRIPTION OF DRAWINGS
[0015] The accompanying drawings are included to provide a further
understanding of the present disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure. The diagrams are for illustration only, which thus is not a limitation of the present disclosure.
[0016] In the figures, similar components and/or features may have the
same reference label. Further, various components of the same type may be distinguished by following the reference label with a second label that distinguishes among the similar components. If only the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label.
[0017] FIG. 1 illustrates an exemplary representation of a test bushing, in
accordance with an embodiment of the present disclosure.
[0018] FIG. 2 illustrates an exemplary representation of conductors inside
the test bushing, in accordance with an embodiment of the present disclosure.
[0019] FIG. 3 illustrates an exemplary representation of the test bushing
when configured with RMU, in accordance with an embodiment of the present disclosure.
[0020] FIG. 4A illustrates an exemplary representation of inner
arrangement of the housing for the test bushing, and FIG. 4B illustrates an exemplary representation of the front portion and the rear portion of the housing for the test bushing, in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION
[0021] The following is a detailed description of embodiments of the
disclosure depicted in the accompanying drawings. The embodiments are in such
detail as to clearly communicate the disclosure. However, the amount of detail
offered is not intended to limit the anticipated variations of embodiments; on the
contrary, the intention is to cover all modifications, equivalents, and alternatives
falling within the scope of the present disclosure as defined by the appended
claims.
[0022] In the following description, numerous specific details are set forth
in order to provide a thorough understanding of embodiments of the present
invention. It will be apparent to one skilled in the art that embodiments of the
present invention may be practiced without some of these specific details.
[0023] The present disclosure relates to the field of ring main unit (RMU).
More particularly the present disclosure related to a test bushing for the RMU.
[0024] The present disclosure elaborates upon a bushing (also referred as
test bushing, herein) adapted to be configured with a ring main unit (RMU). The
bushing includes a housing having a front portion, and a rear portion configured at
an end of the rear portion. A longitudinal axis of the front portion is configured at
a pre-defined angle with a longitudinal axis of the rear portion. An input port
configured inside the front portion; and an output port configured inside the rear
portion, and the output port is electrically configured with the input port through
one or more conductors, wherein the one or more conductors comprises one or
more bends facilitating compact size of the bushing.
[0025] In an embodiment, the one or more bends can be positioned to
ensure a minimum distance between adjacent conductors of the one or more
conductors.
[0026] In an embodiment, the bushing can be mounted along with O-ring
by placing the bushing inside an SF6 tank of the RMU.
[0027] In an embodiment, the bushing can be configured to test and locate
fault in underground cables electrically connected to the RMU.

[0028] In an embodiment, the bushing can be adapted to be configured on
an outer surface of the RMU.
[0029] In an embodiment, while testing the underground cables, a test
input supply can be applied to the underground cables through the input port of
the bushing.
[0030] In an embodiment, the input port can include one or more first ends
of the one or more conductors, and the one or more ends are covered with epoxy
facilitating formation of a cone like structure over the one or more first ends for
insulator boot mounting.
[0031] In an embodiment, the output port can comprise one or more
second ends of the one or more conductors, and the one or more second ends can
be configured to input the test input supply to the underground cables.
[0032] FIG. 1 illustrates an exemplary representation of a test bushing, in
accordance with an embodiment of the present disclosure.
[0033] FIG. 2 illustrates an exemplary representation of conductors inside
the test bushing, in accordance with an embodiment of the present disclosure.
[0034] FIG. 3 illustrates an exemplary representation of the test bushing
when configured with RMU, in accordance with an embodiment of the present
disclosure.
[0035] FIG. 4A illustrates an exemplary representation of inner
arrangement of the housing for the test bushing, and FIG. 4B illustrates an
exemplary representation of the front portion and the rear portion of the housing
for the test bushing, in accordance with an embodiment of the present disclosure.
[0036] A test bushing 100 can include a housing 120 that can be hollow
from inside. The housing 120 can include a front portion 102, and a rear portion
104. The rear portion 104 can be configured at an end 114 of the rear portion 104.
The front portion 102 is configured to remain outside of a tank of a ring main unit
112 and the rear portion 104 is configured to remain outside the tank of the ring
main unit 112. A longitudinal axis of the front portion 102 can be configured at a
pre-defined angle with a longitudinal axis of the rear portion 104. The predefined
angle can be but without limiting to 90 degrees. The pre-defined angle can be

chosen according to elements orientation inside the RMU. An input port 106 can be configured inside the front portion 102. The input port 106 can include one or more terminals for one or more phases.
[0037] In an embodiment, an output port 108 can be configured inside the
rear portion 104. The output port 108 can include one or more terminals for the
one or more phases. The output port 108 can be electrically configured with the
input port 106 through one or more conductors 110. The one or more conductors
can be made of any conductive metal. The one or more conductors 110 can
include one or more bends 116 at predefined positions. The conductors (R, Y, B
phases) 110 should be at a minimum defined distance with each other and with the
earthed parts. The distance between the two phases can be around 18mm. To
achieve this distance 3d bends 116 (also referred as one or more bends, herein)
can be provided at pre-defined positions of the conductors 110.
[0038] In an embodiment, the test bushing 100 can be mounted along with
O-ring by placing the test bushing 100 inside a tank filled with sulfur hexafluoride (SF6) of the RMU 112. The O-ring (not shown) can also be known as a packing or a toric joint. The O-ring can be a mechanical gasket in the shape of a torus and are used to block a path which may otherwise allow a liquid or a gas to escape. The O-ring can be placed into a groove to secure them in place, and then compressed between two surfaces. O-ring can be made but without limiting to nitrile-butadiene rubber (NBR) and other rubber materials.
[0039] In an embodiment, the test bushing 100 can be configured to test
and locate fault in underground cables electrically connected to the RMU 112. The test bushing 100 can be adapted to be extended through an outer surface of the RMU 112. While testing the underground cables, a test input supply can be applied to the underground cables through the input port 106 of the test bushing 100. The input port 106 can include one or more first ends of the one or more conductors, and the one or more ends are covered with epoxy facilitating formation of a cone like structure 118 over the one or more first ends for insulator boot mounting. The output port 108 can comprise one or more second ends of the

one or more conductors, and the one or more second ends can be configured to input the test input supply to the underground cables.
[0040] The present disclosure pertains to a test busing having front portion
102 and a rear portion 104. The front portion 102 and the rear portion 104 can be configured at a pre-defined angle according to an element's orientation inside the ring main unit 112. This can allow effective stacking of the test bushing inside the RMU 112. This can also improve securing a firm connection between the output port and connections arcs inside the RMU 112. The disclosure provides an improved design of the test bushing that can be easily integrated inside the RMU without taking much space. The designs is very much effective in optimum area coverage of the test bushing inside the RMU.
[0041] Moreover, in interpreting the specification, all terms should be
interpreted in the broadest possible manner consistent with the context. In particular, the terms "comprises" and "comprising" should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. Where the specification claims refer to at least one of something selected from the group consisting of A, B, C ....and N, the text should be interpreted as requiring only one element from the group, not A plus N, or B plus N, etc.
[0042] While the foregoing describes various embodiments of the
invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof. The scope of the invention is determined by the claims that follow. The invention is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.
ADVANTAGES OF THE INVENTION
[0043] The proposed invention provides a compact test bushing.

[0044] The proposed invention provides a test bushing that is economic.
[0045] The proposed invention provides a test bushing that is designed
according to element's orientation inside the RMU.
[0046] The proposed invention provides a test bushing that can be
effectively stacked inside the RMU.
[0047] The proposed invention provides a test bushing that can be easy to
handle & assemble.

We Claim:

1. A test bushing (100) adapted to be configured with a ring main unit
(RMU), the test bushing (100) comprises:
a housing (120) having a front portion (102), and a rear portion (104) configured at an end (114) of the front portion (102), wherein a longitudinal axis of the front portion (102) is at a pre-defined angle with a longitudinal axis of the rear portion (104);
an input port (106) configured inside the front portion (102); and an output port (108) configured inside the rear portion (104), and the output port (108) is electrically configured with the input port (106) through one or more conductors (110), wherein the one or more conductors (110) comprises one or more bends (116) facilitating compact size of the test bushing (100).
2. The test bushing (100) as claimed in claim 1, wherein the one or more bends (116) are positioned to ensure a minimum distance between adjacent conductors of the one or more conductors (110).
3. The test bushing (100) as claimed in claim 1, wherein the test bushing (100) is mounted along with O-ring by placing the test bushing (100) inside an SF6 tank of the RMU (112).
4. The test busing (100) as claimed in claim 1, wherein the test bushing (100) is configured to test and locate fault in underground cables electrically connected to the RMU (112).
5. The test bushing (100) as claimed in claim 1, wherein the input port of the test bushing (100) is adapted to be extended through an outer surface of the RMU (112).
6. The test bushing (100) as claimed in claim 1, wherein while testing the underground cables, a test input supply is applied to the underground cables through the input port (106) of the test bushing (100).
7. The test bushing (100) as claimed in the claim 6, wherein the input port (106) comprises one or more first ends of the one or more conductors, and

the one or more ends are covered with epoxy facilitating formation of a cone like structure (118) over the one or more first ends for insulator boot mounting. 8. The test bushing (100) as claimed in claim 1, wherein the output port (108) comprises one or more second ends of the one or more conductors (110), and the one or more second ends are configured to input the test input supply to the underground cables.