FORM 2
The Patents Act 1970
(39 of 1970)
&
The Patent Rules 2003
COMPLETE SPECIFICATION
(See Section 10 and rule 13)
TITLE OF THE INVENTION: SHROUD FOR TERMINALS OF CIRCUIT BREAKERS
APPLICANT:
LARSEN & TOUBRO LIMITED
L&T House, Ballard Estate, P.O. Box No. 278,
Mumbai, 400 001, Maharashtra,
INDIA.
PREAMBLE OF THE DESCRIPTION:
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED

A) TECHNICAL FIELD
[0001] The present invention generally relates to circuit breakers and particularly relates to Molded case circuit breakers (MCCB). The invention more particularly relates to shrouding the terminals of the MCCB.
B) BACK GROUND OF THE INVENTION
[0002] Circuit breakers are the mechanical switching devices capable of making, carrying and breaking currents under normal circuit conditions and also making, carrying for a specified time and breaking currents under specified abnormal circuit conditions. A circuit breaker basically consists of a pair of separable contacts and an interrupting medium. The function of the contacts is to conduct the electrical current, when the breaker is closed and withstand the arcs while interrupting. By making the moving contact to touch the stationary contact, an electric current flows and the breaker is closed. By driving the moving contact away from the stationary contact, an electric arc develops. The current flow stops and the breaker is opened when the arc is quenched.
[0003] In the existing technique, the shroud of MCCB is slide-fitted with the housings of the MCCB firmly. When the MCCB is used at higher voltage breaking, then the severity of arc is very high leading to flashover between the terminal holes of the MCCB and the top surface of the enclosure. The requirement of having higher creepage distance below the terminals and at the same time inspection of cables during and after cabling work is difficult to achieve in the existing technique.
[0004] Thus there is a need for shrouding the terminal holes of the MCCB for providing flexibility and safety to the users during inspection.

[0005] The above mentioned shortcomings, disadvantages and problems are addressed herein and which will be understood by reading and studying the following specification.
C) OBJECT OF THE PRESENT INVENTION
[0006] The primary object of the present invention is to provide an improved shrouding for the terminals of molded case circuit breakers,
[0007] Another object of the present invention is to provide an improved shroud with a lower part including one or more phase barriers.
[0008] Another object of the present invention is to provide an improved shroud which allows the user the flexibility of using normal phase barriers.
[0009] Yet another object of the present invention is to provide an improved shroud which allows the user the flexibility of using top phase barrier along with normal phase barriers.
[0010] Yet another object of the present invention is that the higher level of safety is provided due to shrouding of terminals.
[0011] Yet another object of the present invention is to provide an improved shroud that permits terminal inspection at any point of time.
D) SUMMARY OF THE INVENTION
[0012] The various embodiments of the present invention provide a shroud assembly for MCCB. A shroud for terminals of circuit breakers comprising a lower part, a plurality

of phase barriers arranged on the first lower part and an upper part. The lower part and upper part are joined in such a way that the plurality of phase barriers covers the sides and the top side of the circuit breakers,
[0013] According to another embodiment of the present invention, the MCCB-shroud assembly includes one or more terminal holes, one or more mounting holes, and a upper part of a shroud. The upper part of the shroud is fixed with a top cover of the MCCB by a click fit arrangement or the upper part of the shroud is inserted inside the mounting holes of the top cover of the MCCB by an interference fit arrangement this leads to a higher creepage distance formed below the terminals.
[0014] According to one embodiment of the present invention, the shroud includes a lower part and an upper part. The lower part of the shroud includes one or more phase barriers. The lower part of the shroud is connected to the MCCB using slide fitting arrangement.
[0015] According to one embodiment of the present invention, the portion of the upper part is connected to lower part and the connection forms a hinge arrangement. The upper part includes pips on the top part of the shroud and the pips are fitted inside the grooves of bottom part to form the hinge arrangement,
[0016] According to one embodiment of the present invention, the terminal & terminal holes are shrouded and at the same time inspection of cables are done during and after cabling.
[0017] These and other objects and advantages of the present invention will become readily apparent from the following detailed description taken in conjunction with the accompanying drawings.
E) BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The other objects, features and advantages will occur to those skilled in the art from the following description of the preferred embodiment and the accompanying drawings in which:
[0019] FIG, la-lb illustrates the perspective view of general arrangement of Lower part of shroud & Upper part of shroud with click fit arrangement , according to one embodiment of the present invention.
[0020] FIG. 2 illustrates the shroud assembly, according to one embodiment of the present invention.
[0021] FIG. 3 illustrates the Upper part of shroud with interference fit arrangement according to one embodiment of the present invention.
[0022] FIG. 4a-4b illustrates the front side perspective view of assembling the shroud on the MCCB, according to one embodiment of the present invention.
[0023] FIG.5 illustrates the perspective view of connecting the top part of the shroud to the top cover of the MCCB by click fit method, according to one embodiment of the present invention.
[0024] FIG.6 illustrates the perspective view of connecting the top part of the shroud to the top cover of the MCCB by interference fit method, according to one embodiment of the present invention.
[0025] Although the specific features of the present invention are shown in some drawings and not in others. This is done for convenience only as each feature may be combined with any or atl of the other features in accordance with the present invention.

F) DETAILED DESCRIPTION OF THE INVENTION
[0026] In the following detailed description, a reference is made to the accompanying drawings that form a part hereof, and in which the specific embodiments that may be practiced is shown by way of illustration. These embodiments are described in sufficient detail to enable those skilled in the art to practice the embodiments and it is to be understood that the logical, mechanical and other changes may be made without departing from the scope of the embodiments. The following detailed description is therefore not to be taken in a limiting sense.
[0027] The various embodiments of the present invention provide a shroud assembly for MCCB. The assembly includes one or more terminal holes, one or more mounting holes, a top part of a shroud. The top part of the shroud is fixed with a top cover of the MCCB by a click fit arrangement or the top part of the shroud is inserted inside the mounting holes of the top cover of the MCCB by an interference fit arrangement the lower part of shroud is designed such that a higher creepage distance is formed below the terminals.
[0028] The shroud includes a lower part and an upper part. The lower part of the shroud includes one or more phase barriers. The lower part of the shroud is connected to the MCCB using sliding arrangement. The portion of the upper part is connected to lower part and the connection forms a hinge arrangement. The upper part includes pips on the top part of the shroud and the pips are fitted inside the grooves of bottom part to form the hinge arrangement.
[0029] The hinged shroud assembly is mounted such that the terminal holes are shrouded and at the same time inspection of cables can be done during and after cabling. The shrouding of terminals provides a higher level of safety to the users.
[0030] FIG. la-lb illustrates Lower part of shroud & Upper part of shroud with click fit arrangement, according to one embodiment of the present invention. FIG. 2 illustrates

shroud assembly, according to one embodiment of the present invention. With respect to FIG. 1 and FIG.2, the lower and upper part fixing arrangement is shown and it shows that the upper part hinges over the lower part. The shrouding includes two components namely the lower part and the upper part. The lower part includes four phase barriers 110 that are combined to form an integral lower part. The lower part is connected to the MCCB through a sliding arrangement 102.
[0031] Further when a box clamp is provided with the MCCB, shrouding using a part 104 and a knock out arrangement 106 is provided with the shroud. When box clamp is not used, the knock out can be broken using standard tools like screw driver. The cables strands which are placed inside the box clamp are inspected from upper side of the bottom part 204.The portion of upper part 114 is connected to the bottom part 108 of the lower part.
[0032] The pips 114 present on top of the upper part are fitted inside the grooves of the bottom part 104. The connection of the upper part and the lower part forms a hinge arrangement 202. The upper part is fixed with the MCCB using the terminal holes or mounting holes through at least one of the methods like click fit method, interference method and screws.
[0033] FIG. 3 illustrates Upper part of shroud with interference fit arrangement, according to one embodiment of the present invention. The connection of the upper part and the lower part forms a hinge arrangement 202. The Upper part 314 is placed in the lower part 108 and is connected to form hinged top part arrangement the top part can be fitted with the top cover of MCCB using the part 302.
[0034] FIG. 4a-4b illustrates the front side perspective view of assembling the shroud on the MCCB, according to one embodiment of the present invention. The shroud is assembled on the MCCB through sliding arrangement 102. The sliding ribs of the bottom part are slide inside the MCCB phase barrier grooves and the cable connection is made with the bottom part fixed with the MCCB. The cable strands have inserted inside

the box clamp and the lug connection is proper are inspected from the upper side of the bottom part 204. After the connection is done the hinged top part is connected as shown in FIG.4a. The hinged top part 402 after final inspection of the cables is fixed with the MCCB as shown in FIG.4b.
[0035] FIG.5 illustrates the perspective view of connecting the top part of the shroud to the top cover of the MCCB by click fit method, according to one embodiment of the present invention. FIG,6 illustrates the perspective view of connecting the top part of the shroud to the top cover of the MCCB by interference fit method, according to one embodiment of the present invention. While with respect to FIG.5, the top part is fixed with the top cover of the MCCB by click fit method. The click fit part 502 on the top part 112 of the shroud is click fitted inside the terminal hole of the top cover of MCCB. The part 302 of the top part is inserted inside the cover fixing holes of the top cover of the MCCB, The top cover is interference fit 602 as shown in FIG.6.
G) ADVANTAGES OF THE INVENTION
[0036] The present invention allows the user the flexibility of using the normal phase barriers or the top phase barrier along with the terminal phase barriers. Further this allows termination inspection at any point of time at the same time providing higher level of safety.
[0037] The advantages of the present inventions are that the top part of the shroud can be fitted with the top cover of the MCCB by click fit method and also through the interference fit method. The arrangement of the shroud increases the creepage distance and provides better protection to MCCB against earth faults during short circuit. The shroud suitable for both lug and box clamp type construction. Also it permits inspection of terminals during cabling and after cabling.

[0038] Although the invention is described with various specific embodiments, it will be obvious for a person skilled in the art to practice the invention with modifications. However, all such modifications are deemed to be within the scope of the claims.
[0039] It is also to be understood that the following claims are intended to cover all of the generic and specific features of the present invention described herein and all the statements of the scope of the invention which as a matter of language might be said to fall there between.

CLAIMS
What is claimed is:
1. A shroud for terminals of circuit breakers comprising:
a lower part;
a plurality of phase barriers arranged on the first lower part; and
an upper part;
wherein the lower part and upper part are joined in such a way that the plurality of
phase barriers covers the sides and the top side of the circuit breakers.
2. The shroud according to claim 1, wherein the upper part of the shroud is fixed with a top cover of a MCCB by a click fit arrangement and the upper part of the shroud is inserted inside one or more mounting holes of the top cover of the MCCB by interference fit arrangement.
3. The shroud according to claim 1, wherein the lower part is connected to the MCCB using a sliding arrangement.
4. The shroud according to claim 1, wherein a portion of the upper part is connected to lower part through a hinge arrangement.
5. The shroud according to claim 1, wherein the upper part comprises pips on the top part of the shroud.
6. The shroud according to claim 6, wherein the pips are fitted inside the grooves of the bottom part to form the hinge arrangement.
7. The shroud according to claim 1, wherein the shroud can be mounted on MCCB.

8. The shroud according to claim 1, wherein the terminal holes are shrouded and at the same time inspection of cables can be done during and after cabling.
9. The shroud according to claim 1, wherein the lower part includes a plurality of slides which slide inside the circuit breaker phase barrier grooves to assembly the shroud on the circuit breaker.
10. The shroud according to claim 1, further comprising a cable connecting the lower part to the circuit breaker.
11. The shroud according to claim 1, wherein the lower part of shroud is designed such that the termination with cable lug and box clamp is possible.
12. The shroud according to claim 1, wherein the termination of box clamp termination is possible. The knock out is provided on the box clamp in such a way that the box knock out portion can be broken when the box clamp is not used.