GB2532767A

GB2532767A - Fire proofed enclosures for consumer units

Info

Publication number: GB2532767A
Application number: GB1421063.7A
Authority: GB
Inventors: Alfred Ward Derek
Original assignee: Intumescent Systems Ltd
Current assignee: Intumescent Systems Ltd
Priority date: 2014-11-27
Filing date: 2014-11-27
Publication date: 2016-06-01
Anticipated expiration: 2034-11-27
Also published as: GB201421063D0; GB2532767B

Abstract

An enclosure 10 for a consumer unit, which is capable of being secured to a wall or other surface over the consumer unit to cover the same, comprises side walls 12 which, in use, project from the surface to which the consumer unit is secured to lie alongside side walls of the consumer unit. A lid 14 is hinged to the side walls of the enclosure to provide access to the enclosure and a lining of a fire-proofed material is applied to the inner surfaces of the side walls and the lid. An opening 30 is formed in one or more side walls of the enclosure through which electrical cabling leading to and from the consumer unit can pass and a sheet 32 of fire-proofed material is positioned over the or each such opening. Each sheet is shaped or is capable of being shaped to enable the cabling to pass to or from the enclosure interior.

Description

FIRE PROOFED ENCLOSURES FOR CONSUMER UNITS

This invention relates to fire-proofed enclosures for consumer units which connect external mains electricity to fused electrical circuits of a house or other building. Furthermore, the invention relates to methods of fireproofing such consumer units.

BACKGROUND TO THE INVENTION

Consumer units (also referred to as distribution boards) to which the invention relates comprise a species of distribution boards used principally in domestic premises which function to control the input of mains electricity to the premises and to distribute this electricity to circuits within the premises. Such units incorporate manually operable means for double-pole isolation of incoming circuit(s) and an assembly of fuses or circuit breakers for isolating individual electrical circuits operating within the premises.

Many consumer units comprise plastics housings which provide limited protection to fuses and wiring present in the unit in the event of a fire. One consequence of this is that all electrical power within a premises is often lost within a relatively short period of time in the event of a fire.

In recognition of the need to fire-proof consumer units, legislation is to be enacted in January 2015 which will require that all consumer units are produced from or comprise non-combustible materials. This legislation will effectively mean that all plastics consumer units will either need to be replaced with ones produced from a noncombustible material such as metal, or be effectively fire-proofed.

To replace existing consumer units produced from plastics or other combustible materials would be both costly and time consuming. To do so would require involving the appropriate authority to switch off the mains electricity supply to the building in question and then, once the existing unit has been removed, installing and rewiring the replacement unit before once more involving the appropriate authority to reconnect the mains supply to the building.

The present invention provides a less costly and more convenient way of meeting the aforementioned legislation by providing enclosures which effectively fire-proof consumer units produced from combustible materials. Such enclosures will ensure that lighting and other electrically powered services present in a house are maintained for a period in excess of one hour in the event of a fire. Maintenance of lighting could, in particular, be crucial in assisting the escape of residents trapped in the building in the event of a fire.

SUMMARY OF THE INVENTION

In one aspect the invention provides an enclosure for a consumer unit which is capable of being secured to a wall 30 or other surface over the consumer unit to cover the same, the enclosure comprising side walls which, in use, project from the surface to which the consumer unit is secured to lie alongside the side walls of the consumer unit, a lid hinged to the side walls of the enclosure to provide access to the enclosure, a lining cf a fireproofing material applied to the inner surfaces of the side walls and the lid, an opening formed in one or more side walls of the enclosure through which electrical cabling leading to and from the consumer unit can pass and a sheet of fire-proofed material positioned over the or each such opening, each said sheet being shaped or capable of being shaped to enable said cabling to pass to or from the enclosure interior.

The enclosure is preferably produced from steel, preferably a steel powder coated with a non-combustible coating.

Flanges may project outwardly from the side walls of the enclosure for connecting the enclosure to a wall or other surface to which the consumer unit is secured.

Preferably, the enclosure dimensions are such that the enclosure walls are spaced approximately 20mm from the consumer unit to be covered and the enclosure lid is spaced approximately 25mm from the upper surface of the consumer unit to be covered.

Catches preferably project upwardly from the rim of one side wall and co-operate with complementary openings formed in the lid to locate the lid firmly in place when the enclosure is to be closed.

The lid may be provided with a foiled edge which extends around the front and side edges of the lid.

The side walls of the enclosure preferably include slots through which cabling can pass to and from a consumer unit located within the enclosure. The slots are preferably covered by sheets which intumesce in the presence of fire.

The internal surfaces of the side walls and the lid may be 5 lined with one or more heat resistant sheets which contain an intumescent material.

In another aspect there is provided a method for fireproofing a wall mounted consumer unit which comprises the steps pf enclosing a wall-mounted consumer unit within an enclosure comprising side walls and a lid, the inner walls of the enclosure being lined with fire proofing material and openings being formed in at least one side wall through which electric cables connected to the consumer unit can pass.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described by way of example only with reference to the accompanying drawings in which:-Figure 1 is a perspective view from one side of an enclosure in accordance with the invention with the lid of 25 the enclosure raised; Figure 2 is a perspective view of the enclosure illustrated in Figure 1 from the opposite side; Figure 3 is a perspective view of the enclosure illustrated in Figures 1 and 2 when closed; and Figure 4 shows a catch of the illustrated enclosure.

DETAILED DESCRIPTION OF THE INVENTION

A steel enclosure 10 in accordance with the invention is illustrated in Figures 1 to 3 of the drawings. Enclosure 10 is typically produced from 1.2mm gauge steel strip. The steel is preferably powder coated with a non-combustible coating. The enclosure comprises side walls 12 and a lid 14 connected through hinges to the upper rim 18 of one side wall. The hinges are typically steel piano hinges.

Flanges 20 formed with through holes project outwardly from the side walls 12 for securing the enclosure to the wall or other surface to which the consumer unit (not shown) to be protected is secured.

The enclosure is dimensioned to fit over the respective consumer unit with a limited clearance between the opposed sides of the unit and the sides and lid of the enclosure. Typically the enclosure walls are spaced approximately 20mm from the sides of the consumer unit to be covered and the enclosure lid is spaced approximately 25mm from the upper surface of the consumer unit to be covered. These dimensions are given by way of example only and other dimensions could readily be adopted.

Catches 22 project upwardly from the rim 24 of the side wall opposite to that on which the lid 14 is supported and co-operate with openings 26 formed in the lid to locate the lid firmly in place when the enclosure is to be closed. As is shown in Figure 4 each catch includes a rotatable member 28 which can pass through the respective opening 26 and then be turned to lock the lid in place.

The lid is provided with a foiled edge which extends around the front and side edges of the lid. This foiled edge may comprise a 25mm wide strip of Multigraf (registered trademark of the Applicant) intumescent. A 5 layer of Envirograf (registered trademark of the Applicant) 3mm felt paper may also be adhered to the internal face of the lid.

The side walls of the enclosure include slots 30 through which cabling can pass to and from the consumer unit located within the enclosure. These slots are covered by sheets 32 which intumesce in the presence of fire. Typically, the sheets 32 comprise a polyurethane cloth containing a quantity of an intumescent material. The cloth may be doubled to provide additional protection. The sheets 32 are typically pct riveted and washer fixed to the side walls of the enclosure. These sheets can readily be cut to enable cables, conduits or trunking to pass into or out of the enclosure. In the event of a fire, the sheets 32 will intumesce to completely close off the slots 30.

The internal surfaces of the side walls 12 and the lid 14 are lined with heat resistant sheets 34 which typically include an intumescent material. In a preferred arrangement, each internal surface of the enclosure is lined with two layers of Envirograf felt paper adhered to the internal surfaces of the enclosure side walls and the internal surface of the lid using an IA adhesive and a foiled Multigraf layer of intumescent material wrapped in a plastic film.

For assembly, the enclosure is simply screwed to the wall on which the existing consumer unit is located with the existing unit entirely covered by the enclosure. Electrical cabling to the unit is accommodated by the side wall slots 30, the sheets 32 being cut accordingly. If appropriate, intumescent containing sealant is provided between the rear edge of the enclosure and the wall.

When the lid 14 is closed, the consumer unit located inside the enclosure is entirely fire-proofed. In the event of a fire, the intumescent content of the enclosure rapidly expands to prevent any damage to the consumer unit thereby ensuring continuity of electricity to the building.

It will be appreciated that the foregoing is merely exemplary of fire-proofed enclosures in accordance with the invention and that modifications can readily be made thereto without departing from the scope of the invention as set out in the appended claims.

Claims

CLAIMS1. An enclosure for a consumer unit which is capable of being secured to a wall or other surface over the consumer unit to cover the same, the enclosure comprising side walls which, in use, project from the surface to which the consumer unit is secured to lie alongside the side walls of the consumer unit, a lid hinged to the side walls of the enclosure to provide access to the enclosure, a lining of a fire-proofed material applied to the inner surfaces of the side walls and the lid, an opening formed in one or more side walls of the enclosure through which electrical cabling leading to and from the consumer unit can pass and a sheet of fire-proofed material positioned over the or each such opening, each said sheet being shaped or capable of being shaped to enable said cabling to pass to or from the enclosure interior.
2. An enclosure as claimed in claim 1 produced from steel.
3. An enclosure as claimed in claim 2 wherein the steel is powder coated with a non-combustible coating.
4. An enclosure as claimed in any one of the preceding claims wherein flanges project outwardly from the side walls of the enclosure for connecting the enclosure to a wall or other surface to which the consumer unit is secured.
5. An enclosure as claimed in any one of the preceding claims wherein the enclosure dimensions are such that the enclosure walls are spaced approximately 20mm from the consumer unit to be covered and the enclosure lid is spaced approximately 25mm from the upper surface of the consumer unit to be covered.
6. An enclosure as claimed in any one of the preceding claims wherein catches project upwardly from the rim of one side wall and co-operate with complementary openings formed in the lid to locate the lid firmly in place when the enclosure is to be closed.
7. An enclosure as claimed in any one of the preceding claims wherein the lid is provided with a foiled edge which extends around the front and side edges of the lid.
8. An enclosure as claimed in any one of the preceding claims wherein the side walls of the enclosure include slots through which cabling can pass to and from a consumer unit located within the enclosure.
9. An enclosure as claimed in claim 8 where the slots are covered by sheets which intumesce in the presence of fire.
10. An enclosure as claimed in any one of the preceding claims wherein the internal surfaces of the side walls and the lid are lined with heat resistant sheets which include an intumescent material.
11. A method for fire proofing a wall mounted consumer unit comprising the steps of enclosing the wall mounted consumer unit within an enclosure comprising side walls and a lid, the inner surfaces of the side walls and the lid being lined with an intumescent containing fire proofing material and openings being formed in at least one side wall through which electric cables can pass to and from the consumer unit.
12. An enclosure for a consumer unit substantially as herein described and as described with reference to the accompanying diagrammatic drawings.