GB2305007A - Consumer units - Google Patents

Abstract

A base member (10), for a consumer unit including a cover member of generally box-shape configuration to define an enclosure with the base member (10), comprises peripheral portion (12) for locating directly against a wall, and a raised portion to provide a mounting plinth (13) for locating a main switch for an incoming power supply and a plurality of protection devices for outgoing sub-circuits. The raised portion has a mounting surface (24) and side walls (26) formed with apertures (28) therein to facilitate the passage of cables beneath the mounting surface (24).

Description

ImDrovements in and Relating to Consumer Units The invention relates to electrical consumer units primarily, but not exclusively, such consumer units intended for domestic use.

Consumer units comprise an enclosure containing a switch or circuit breaker for the incoming supply, a number of outgoing sub-circuits each having its live side protected by a fuse or circuit breaker and means interconnecting the live supply with the fuses or circuit breakers and interconnecting the neutrals and grounds.

European patent EP-O 325 370 discloses an enclosure for an electrical consumer unit having a base member formed to mount a main switch and protection devices and to be located directly against a wall, in use, to enable cable entry thereto substantially coplanar with the internal surface of the base member.

A cover therefor is formed to provide, with the base member, a box-shaped enclosure and has punch-out portions in its side walls to facilitate cable entry therethrough.

Although such a consumer unit has proved extremely successful in practice, when cables enter from the top or bottom thereof and are required to be connected at the other side of the unit, they have to be located around the mounting arrangement and the unit can become cluttered with such cabling. Furthermore incoming cable ends cannot be trimmed to a single length and stripped for connection.

Furthermore with this prior arrangement the live bus bar is fully exposed when no devices are attached thereto and blanking members have to be provided for unused positions. No provision is made to enable bus bars to be split to provide isolated sections or to allow neutral bars to be fitted at optional positions.

Accordingly, it is an object of the present invention (which invention is defined in the appended claims) to overcome or mitigate at least one of the foregoing problems.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Fig. 1 is a perspective view of a base member for a consumer unit; Figs. 2 and 3 are perspective views from above and below, respectively, of a mounting module having two locating positions; Figs. 4 and 5 are perspective views from above and below, respectively, of a mounting module similar to that shown in Figs. 2 and 3 but having four locating positions; Figs. 6 is a plan view from below of the mounting module of Figs. 4 and 5 showing live and neural bus bars located thereon, and Figs. 7 and 8 are perspective views of a blanking wedge member or use with the mounting modules of Figs.

2 to 6.

Referring now to Fig. 1 of the drawings there is shown a base ember 10 for a consumer unit comprising a substantially planar, rectangular peripheral portion 12 formed from synthetic plastics electrically insulating material and a centrally located raised plinth portion 13.

Peripheral portion 12 is formed with a plurality of apertures 1 located at each corner thereof whereby it may be fixed to a wall (not shown) by means of screws (not shown) or other suitable fixing means. A plurality of locating lugs 16, 18 are disposed around the outer periphery for locating a cover member which may be of any suitable box-shape form and preferably of a form as shown in Figs. 26 to 30 of abovementioned patent specification EP-O 325 370. Cover fixing posts 20 with internal screw threads 22 are located adjacent each lateral edge of base portion 12. The lugs 16, 18 and posts 12 are also moulded integrally with base portion 12.

The raised plinth portion 13 comprises a mounting surface 24 lying coplanar with base portion 12 and side walls 26 which extend between base portion 12 and mounting surface 24. The top and bottom side walls 26 are formed with apertures 28 to allow the passage of cables therethrough beneath mounting surface 24. The mounting surface 24 is formed with location apertures 30 to receive mounting clips or protrusion of mounting modules for switches and protection devices as will hereinafter be more fully described.

Referring now to Figs. 2 to 6 of the drawings there are shown two mounting modules for mounting a main switch for an incoming power supply and protection devices for outgoing sub-circuits, Figs. 2 and 3 showing such a module 32 having two locating positions and Figs. 4, 5 and 6 showing such a module 34 having four locating positions.

Each of the mounting modules 32 and 34 comprise a generally sheet-form mounting member 36 with side walls 38 depending downwardly therefrom. The upper surface (Figs. 2 and t) of each mounting member 36 is formed, at each locating position, with a boss comprising a pair of upstanding, parallel, spaced, triangular lugs 40 having their apices interconnected by a solid, circular cross-section member 42 for accommodating an electrically insulating C-clip mounting of a circuit breaker or switch. Pairs of access apertures 44 are provided to accommodate electrically conductive C-clips for connection to a bus bar located on the lower surface of mounting member 36 as will hereinafter be more fully described.An upstanding partition 46 is located adjacent apertures 44 to separate a mounting channel portion 48 from the remainder of the upper surface for locating a terminal block (not shown) for connection of outgoing sub-circuit cabling.

The lower surface (Figs. 3, 5 and 6) of each mounting member 36 is formed, at each locating position, with a rectangular cross-section socket portion 50, and a downwardly projecting bracket portion 54. A downwardly projecting lip 52 and a bracket 56 are located between each adjacent pair of locating positions. A generally comb shaped bus bar 58 (Fig. 6) is located with a tooth portion inserted in each socket portion 50 and overlapping access apertures 44 to be contactable from the upper surface of the mounting member 36. Portions of the body of bus bar 58 between each tooth portion are located beneath brackets 56 and the outer edge of the body portion is retained in position by lips 52. A neutral bus bar 60 (Fig. 6) is located in one locating position with one end located in socket portion 50 and the other end retained beneath bracket 54.

The lower surface of each mounting member 36 is also formed with downwardly projecting strengthening partitions 62 and internally apertured bosses 64 for the attachment of the terminal block in the mounting channel 48 on the upper surface.

Top and bottom side walls 38 are formed with slots to allow the passage of cabling through the mounting module beneath the lower surface of mounting member 36 and are formed at their lower edges with mounting protrusion or clips 68 for engagement in the location apertures 30 in mounting surface 24 of the plinth portion 13 of base member 10 (Fig.l). The mounting surface 24 is formed with location apertures 30 such as to mount two mounting modules juxtaposed, one two locating position module 32 (Figs. 2 and 3) and one four locating position module 34 (Figs 4, 5 and 6).

The side walls 38 of each module 32 and 34 are each formed with a slot 70 so that when two or more modules are juxtaposed a single comb-shaped bus bar 58 can be utilised to span the locating positions of such modules. The edges of each slot 70 are formed as arcuate section tongue portions to be engagable in cooperating grooves formed in the outer edges of a wedge-shape blanking member 72 (Figs 7 and 8). The modules 32 are moulded so as to be braced inwardly at such slots 70 so that when a blanking member 72 is engaged in a slot 70, in an outer wall of an assembly of modules, it is retained in position without any further fixing being required.

With the arrangement shown the mounting modules provide mounting of a bus bar 58 with finger safety from the upper surface of mounting member 36 and also provide for mounting a neutral bus bar 60 at any required locating position.

Although mounting modules 32 and 34have been described for mounting on the base member 10 of Fig. 1, such modules could be mounted on a planar base member or on the base of a box-shaped container of a consumer unit. Furthermore the mounting surface 24 of plinth portion 13 of base member 10 could be integrally moulded to provide mounting for a switch and protection devices.

Claims (12)

1. A base member, for a consumer unit including a cover member of generally box-shape configuration to define an enclosure with the base member, comprising a peripheral portion in the form of a plate-form area for locating directly against a wall, in use, and a raised portion to provide a mounting plinth for locating a main switch for an incoming power supply and a plurality of protection devices for outgoing subcircuits thereon, the raised portion having a mounting surface co-planar with the peripheral portion and side walls formed with apertures therein to facilitate the passage of cables beneath the mounting surface.

2. A base member as claimed in claim 1 moulded from an electrically insulating material and wherein said mounting surface is formed integrally with mounting formations to receive and mount said main switch and protection devices.

3. A base member as claimed in claim 1 wherein said mounting surface is formed with apertures therethrough to facilitate attachment thereto of at least one mounting module formed for mounting said main switch and protection devices.

4. A base member as claimed in claim 3 in combination with a mounting module located thereon which is moulded from an electrically insulating material, comprising a generally sheet-form mounting member with side walls depending downwardly therefrom, the upper surface of the mounting member having integrally formed mounting protrusions and apertures for providing at least two locating positions, each for locating a main switch for an incoming power supply or a protection device for an outgoing sub-circuit, the lower surface of the mounting member having integrally formed mounting protrusions, located to correspond with said locating positions, for locating a bus bar transversly spanning a plurality of said locating positions or locating a neutral bus bar longitudinally at a single locating position.

5. A combination as claimed in claim 4 wherein the mounting module includes mounting protrusions formed at the lower edges of at least two of said side walls engaged in said apertures in the mounting surface of the base member.

6. A combination as claimed in claim 5 wherein the mounting module has the attachment mounting protrusions formed at the lower edges of the top and bottom side walls, relative to the longitudinal direction of the locating positions, and apertures or slots are formed in such top and bottom side walls to facilitate the passage of cables therethrough.

7. A combination as claimed in claim 6 wherein the longitudinally extending side walls of the mounting member are each formed with a slot to facilitate location of a single transverse bus bar to span the locating positions of two or more juxtaposed mounting modules.

8. A combination as claimed in claim 7 wherein each slot in each longitudinally extending side wall of the mounting member is formed to be splayed outwardly from the mounting member and the module is moulded so as to be braced inwardly at such slots whereby a wedgeshaped blanking member can be inserted and retained in a slot which is formed in an outer side wall, in use.

9. A combination as claimed in claim 8 further in combination with at least one blanking member wherein the side edges of the slot in the mounting member and blanking member are formed with cooperating arcuate cross-section tongue and groove formations.

10. A combination as claimed in any one of claims 4 to 9 inclusive wherein the lower surface of the mounting member is formed with downwardly depending support partitions between each adjacent pair of locating positions.

11. A base member for a consumer unit substantially as hereinbefore described wtih reference to Fig. 1 of the accompanying drawings.

12. A base member for a consumer unit in combination with at least one mounting module substantially as hereinbefore described with reference to the accompanying drawings.