FORM 2
THE PATENT ACT 1970
&
THE PATENTS RULES, 2003 COMPLETE SPECIFICATION
(See section 10 and rule 13)
1. TITLE OF THE INVENTION:
"Insulated Barrier for Vertical bus bars in Motor Control Center"
2. APPLICANT:
(a) NAME: Larsen & Toubro Limited
(b) NATIONALITY: Indian Company registered under the
provisions of the Companies Act-1956.
(c) ADDRESS: Larsen & Toubro Limited
L&T House, Ballard Estate,
P.O Box No. 278, Mumbai 400001, INDIA.
3. PREAMBLE TO THE DESCRIPTION:
COMPLETE
The following specification
particularly describes the invention and the manner in which it is to be performed.

Insulated Barrier for Vertical bus bars in Motor Control Center
Field of invention
The present invention relates to motor control centers, and more particularly to an insulated barrier for vertical bus bar of a motor control center.
Background of the invention
Low voltage switchgear and control gear assemblies having input system voltage greater than 1000V for AC systems and 1500V for DC systems are particularly divided into Power Control Centre (PCC, hereinafter) in the upstream and Motor Control Centre (MCC, hereinafter) in the downstream.
There are certain critical parameters that are followed while designing and selecting switchboards for a particular application such as for example type of application , Current rating of bus bars, Circuit breaker rating, number of outgoing feeders, Short circuit breaking, making and withstand capacities, Thermal performance, Internal arc withstand capability and the like.
Generally, the MCC is a multi-compartment steel enclosure that performs various protection, monitoring and control functions in industrial environment. In such MCCs, three-phase or three-phase plus neutral electric power is fed from main conductors. Within the motor control center enclosure, internal electric power is fed from mains to the horizontal and vertical bus conductors called bus bars. In MCC various switchgear, control devices, protective circuit devices, programmable logic controllers, motor drives and the like are housed in a large enclosure that may be sub-divided into compartments. These compartments are generally draw-out units, typically known as feeders or modules or drawers or buckets. The modules contain electrical components such as one or more circuit

breakers, starters, overload protectors, indicating lamps, auxiliary devices. The vertical bus bars distribute power to these compartments.
The vertical bus bars are often mounted on insulated housing to prevent accidental personnel contact. The vertical bus bars of the motor control centers in particular are likely to create inadvertent electrical contact by a technician in plurality of operational instances such as installation, operation, withdrawal or removal of MCC units / modules / feeders / buckets from the enclosure. The prior art insulating barriers fail to prevent complete access to the vertical bus bars. The prior art vertical bus bar supporting systems have limited encapsulation that fail to prevent face to face contact of the bus bars. There are few attempts seen in the art for providing complete encapsulation of the bus bars. However, these encapsulation means fail to facilitate sufficient creepage distance between the phases."
Accordingly, there exists a need of an insulated barrier assembly for vertical bus bars in motor control center that overcomes all the drawbacks of the prior art.
Objects of the invention
An object of the present invention is to provide an insulated barrier assembly that facilitates complete insulation to a plurality of vertical bus bars of a motor control center
Summary of the invention
Accordingly, the present invention provides an insulated barrier assembly that provides complete insulation of a plurality of vertical bus bars of a motor control center. The insulated barrier assembly comprises a plurality of bus bar supports providing support to the vertical bus bars by providing entire encapsulation thereof. The insulated barrier assembly includes a bus cover having a plurality of

knock outs, a plurality of louvers, a plurality of holes, a plurality of ridges, a plurality of ribs and at least one hexagonal platform. Each of the knock outs is having a bridge formed by a slit located around an entire periphery thereof. The knock outs after being broken form a window therein. The window facilitates positioning of a plurality of bus bar fixed contacts therein. The ridge acts as a locator for fixing the bus cover onto the bus bar support. The louvers facilitate natural ventilation of heat from the vertical bus bars thereby reducing temperature thereof. The hexagonal platform is positioned in proximity to the bus bar fixed contacts for adding rigidness to the bus cover. The bus bar supports are made through a plurality of electrically non-conductive support members. The ridge assists in complete encapsulation of the vertical bus bar thereby increasing a creepage distance between successive phases thereof. The ribs add mechanical integrity to the bus cover. The bus cover includes a roof that assists in complete encapsulation of the vertical bus bars. The hexagonal platform adds strength to the bus cover for bearing a pressure that is exerted in making a contact with a draw-out assembly. The plurality of holes assists in direct fixing of the bus cover on the bus bar supports through a respective plurality of self-tapping screws.
Brief description of the drawings
FIG. 1 is a front view of an insulated barrier assembly within a motor control center constructed in accordance with the present invention;
FIG. 2 is a perspective view of the insulated barrier assembly of FIG. 1;
FIG. 3 is a left hand side perspective view of the insulated barrier assembly of FIG. 1;
FIG. 4 is a right hand side perspective view of the insulated barrier assembly of FIG. 1;

FIG. 5 is a perspective view of the insulated barrier assembly of FIG. 1;
FIG. 6 is a front view of a bus bar cover of the insulated barrier, assembly of FIG.
l;
FIG. 6A is a top view of the bus bar cover of FIG. 6;
FIG. 7 is a rear perspective view of the bus bar cover of FIG. 6;
FIG. 8 is a front perspective view of the bus bar cover of FIG. 6;
FIG. 9 is a partially expanded rear perspective view of the bus bar cover of FIG. 6;
FIG. 10 is a partially expanded front perspective view of the bus bar cover of FIG. 6 showing details of a plurality of knock-outs;
FIG. 11 is a cross sectional view of the bus bar cover of FIG. 6 showing details of the plurality of knock-outs;
FIG. 12 is a front perspective view of the bus bar cover of FIG. 6 showing a window for power contacts;
FIG. 13 is a partially expanded view of the bus bar cover of FIG. 6 showing details of a plurality of louvers;
FIG. 14 is a cross sectional view of the bus bar cover of FIG. 6 showing details of the plurality of louvers; and
FIG. 15 is a partially expanded rear view of the bus bar cover of FIG. 6 showing details of a plurality of ribs and a plurality of hexagonal platforms.

Detailed description of the invention
The foregoing objects of the present invention are accomplished and the problems and shortcomings associated with the prior art, techniques and approaches are overcome by the present invention as described below in the preferred embodiments.
Referring to FIGS. 1-5, an insulated barrier assembly 100 in accordance with the present invention is shown. The insulated barrier assembly 100 includes a bus cover/ barrier 1 that is fixed on a plurality of bus bar supports 2. The bus bar supports 2 provide a support for a plurality of vertical bus-bars 3. The bus bar supports 2 include a plurality of individual support members that are electrically non-conductive. The bus bar supports 2 are preferably made of an insulating material that also provides strength to the vertical bus in case of short-circuit in addition to providing sufficient creepage distance between phases. An incoming electrical supply is fed through the vertical bus-bars 3 in this one particular embodiment. The bus bars 3 provide supply to a plurality of bus bar fixed contacts 4.
Referring to FIGS. 6, 6A and 7, the bus cover 1 has a front side 5, a rear side 6, a top side 7 and a bottom side (not shown). The bus cover 1 includes a plurality of user configured features respectively defined on the front side 5 and the rear side 6 adapted to drastically reduce fixing time needed for fixing to the structure. The front side 5 and the rear side 6 define a structure that provides dedicated 'arc-fault free' zones for the vertical bus bars 3 in this one particular embodiment. The structure of the bus cover 1 is such that complete encapsulation of the electrical contacts is achieved. The structure defined by the front side 5 and the rear side 6 is user friendly and adds substantial rigidity and mechanical integrity in assembling the bus cover 1 over the bus bar supports 2. The structure of the bus cover 1 is designed to comply with IP4X protection from solid foreign objects of size less

than 1mm in diameter. The bus cover 1 substantially'improves aesthetic look of the insulated barrier assembly 100.
Now referring to FIG. 8, the front side 5 of the bus bar cover 1 includes a plurality of specially designed knock-outs 1A. The knock outs 1A are configured to be removed from their position for positioning the bus-bar fixed contacts 4 on the assembly 100. A roof or shed IE is provided in this one embodiment for complete stacking of the barrier 1 with succeeding barrier I. The roof or shed IE is preferably located at a bottom side of the assembly 100. The roof or shed IE assists in achieving complete encapsulation in addition to achieving IP4X protection from solid foreign objects of size less than 1mm in diameter.
Referring to FIGS. 9-12, the rear side 6 includes a plurality of holes 1G that facilitate direct fixing of the bus bar cover 1 on the insulating bus bar supports 2. A plurality of self-tapping screws is used that position within the holes 1G for fixing the bus bar cover 1 on the bus bar supports 2. In this one particular embodiment, the rear side 6 includes six holes 1G. However, it is understood that the number of holes -1G may vary in other alternative embodiments of the assembly 100.
Each of the knock-outs IA consists of a small bridge or wall or protrusion 1AB for keeping the knock-outs in position. The knock-outs are adapted to be broken by pushing or breaking the wall / bridge 1AB using a hand tool. The knock-outs are provided with a slit / cut IAS around the entire periphery thereby forming only the small bridge 1AB. A window 1AW is formed after removing the knock-out. The window 1 AW facilitates assembly of the bus-baT fixed power contacts 4.
A specially designed ridge IF is provided for complete encapsulation in this one embodiment. The ridge IF helps to increase the creepage distance between successive phases of vertical bus-bars 3. The ridge 3 also acts as a locator for fixing the barrier 1 onto the bus-bar support 2 (refer Fig. 9).

Referring to FIGS. 13-15, a plurality of louvers IB is provided on the cover 1 for providing better heat flow from the vertical bus-bars 3. The louvers IB are provided in numbers sufficient enough to reduce the temperature of bus-bars 3 as well as contacts 4 preferably by efficient natural ventilation. Each of the louvers 1B has a predefined slot that complies with IP4X protection from solid foreign objects of size less than 1mm in diameter. A plurality of special ribs 1C is provided on the cover 1 to add strength to the entire structure of the cover 1. The ribs 1C have a substantially superior mechanical integrity that is achieved by the shape of the ribs 1C.
A hexagonal platform ID is provided to strengthen the barrier assembly 100 near passage of bus-bars fixed contacts 4. The hexagonal platform ID increases the rigidness of the bus bar cover 1 during the pressure exerted while making the contact with a draw-out assembly.
Advantages of the present invention are:
1. The insulating cover 1 is a relatively simple and features engineered construction.
2. The structure of the insulating cover 1 helps to a dedicated 'arc-fault free' zones for vertical bus bars 3.
3. The insulating cover 1 provides complete encapsulation of the assembly 100
4. The insulating cover 1 is having a design that is user friendly
5. The assembly 100 substantially reduces the fixing time in comparison to a flat barrier used for fixing to the structure
6". The barrier 1 is adapted to be directly on the insulating bus bar supports 2
with holes 1G using the self-tapping screws. 7. The insulating assembly 100 is highly rigid and has a mechanical integrity
that is achieved due to special structure of the bus cover 1

8. The total structure of barrier assembly 100 complies with IP4X protection from solid foreign objects of size less than 1mm in diameter.
9. The structure of the barrier assembly 100 has highly improved aesthetics
10. The knock-outs of the assembly 100 are configured to be easily broken off by pushing, breaking the wall / bridge (1AB) & with the help of the hand tool to facilitate the assembling of bus-bar fixed power contacts 4
11. The louvers advantageously facilitate better heat flow from the vertical bus-bars 3 by reducing the temperature thereof by efficient natural ventilation
12. The ribs IB advantageously strengthen the entire barrier structure and impart superior mechanical integrity that is achieved by the shape of ribs IB.
13. The hexagonal platform ID strengthens the barrier 1 near passage of busbars fixed contacts 4 to add rigidity to the barrier 1 during pressure exerted while making the contact with the draw-out assembly.
The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching.
The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, to thereby enable others skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omission and substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but such are intended to cover the application or implementation without departing from the spirit or scope of the present invention.

We Claim:
1. An insulated barrier assembly providing complete insulation of a plurality of
vertical bus bars of a motor control center, the insulated barrier assembly
comprising:
a plurality of bus bar supports facilitating support to the vertical bus bars by providing entire encapsulation thereof; and
a bus cover having a plurality of knock outs, a plurality of louvers, a plurality of holes, a plurality of ridges, a plurality of ribs and at least one hexagonal platform, the knock outs having a bridge formed by a slit located around an entire periphery thereof, the knock outs having a configuration adapted to form a window therein, the window facilitating positioning of a plurality of bus bar fixed contacts therein, the ridge acting as a locator for fixing the bus cover onto the bus bar support, the louvers facilitating natural ventilation of heat from the vertical bus bars thereby reducing temperature thereof, the hexagonal platform positioning in proximity to the bus bar fixed contacts thereby adding rigidness to the bus cover.
2. The insulated barrier assembly as claimed in claim 1, wherein the bus bar supports are made through a plurality of electrically non-conductive support members.
3. The insulated barrier assembly as claimed in claim 1, wherein the ridge assists in complete encapsulation of the vertical bus bar thereby increasing a creepage distance between successive phases thereof.
4. The insulated barrier assembly as claimed in claim 1, wherein the ribs add mechanical integrity to the bus cover.

5. The insulated barrier assembly as claimed in claim 1, wherein the bus cover includes a roof that assists in complete encapsulation of the vertical bus bars.
6. The insulated barrier assembly as claimed in claim 1, wherein the hexagonal platform adds strength to the bus cover for bearing a pressure that is exerted in making a contact with a draw-out assembly.
7. The insulated barrier assembly as claimed in claim 1, wherein the plurality of holes assists in direct fixing of the bus cover on the bus bar supports through a respective plurality of self-tapping screws.