GB2059188A

GB2059188A - Junction box for a central heating system and method of use

Info

Publication number: GB2059188A
Application number: GB8029415A
Authority: GB
Original assignee: Guerrati F A
Current assignee: Guerrati F A
Priority date: 1979-09-11
Filing date: 1980-09-11
Publication date: 1981-04-15

Abstract

A junction box for a central heating system, comprises terminals 24 for respective connection to terminals of the components of the system. The junction box terminals are appropriately designated and are interconnected by a pre-connected circuit board 23 on which the terminals are mounted. The method of connection in accordance with the invention requires simply the wiring of the component terminals to the appropriate junction box terminals. <IMAGE>

Description

SPECIFICATION Junction box for a central heating system and method of use The invention relates to a junction box for a central heating system, typically a domestic system, and a method employing such a junction box.

A domestic central heating system may have, typically, a boiler with an electrically actuated fuel valve; a water pump; a hot-water cylinder; an electrically operated diverting valve or one or more straight through valves; a room thermostat; a hot-water cylinder thermostat; and a time clocki programmer. All of these components require electrical interconnection and connection to the mains supply. The practice hitherto has been to provide the necessary connections by means of a terminal block.

However, the connections are complex and require a high degree of skill.

An object of the invention is to provide a junction box and method of use which simplifies the interconnection procedure.

According to one aspect of the invention there is provided a junction box for a central heating system, the junction box being provided with a set of terminals for connection to specific terminals of the components of the system; the junction box having markings which designate the junction box terminals with respect to the component terminals to which they should be connected; and a circuit board pre-connected to interconnect the junction box terminals in the required manner.

Preferably the junction box terminals are screw terminals mounted directly on the circuit board. The terminals may be mounted on the face of the board opposite to that carrying the interconnections so that the terminal face may carry the terminal designations. Preferably the board is a printed-circuit board and at least some of the interconnections are printed-circuit connections. The terminal designations themselves may be made by printed-circuit techniques.

Preferably the junction box includes a mains fuse and an on/off switch. It is envisaged that the junction box may further incorporate the programmer.

According to another aspect of the invention there is provided a method of connecting a central heating system having a number of electrical components including temperature and time control units, the method consisting in taking a junction box as hereinbefore described wherein the terminal designations correspond to terminals of the components of the system, and connecting the junction box terminals to the component terminals as designated.

The invention will be further described with reference to the accompanying drawings, of which Figure 1 is a wiring diagram for a typical domestic central heating system, Figure2 is an elevation of a junction box in accordance with the invention for use with the system of Figure land, Figure 3 is an elevation showing the markings on the terminal face of the printed-circuit board of Figure 2.

Referring to Figure 1 there is shown the diagram of a domestic central heating system which comprises a boiler 10 with an electrically actuated fuel valve and a water pump 11. A hot-water cylinder is provided with a thermostat 12 designated L 6190 B and there is a room thermostat 13 designated T 6060 B. A motor-driven diverting valve 14 is designated V 4073 A and is effective to control the flow of hot water which heats the radiators and the hot-water cylinder. A time clockiprogrammer 15 is connected to the mains supply 16 and is effective to supply electrical power to the system at pre-determined times.

The interconnections between the components of the system are made by means of a terminal block 17 having interconnected pairs ofterminals to which wires from the terminals of the system components are appropriately connected.

Referring to Figure 2 there is shown a terminal box in accordance with the invention. The box has a body 20 with fixing holes 21 for screw-mounting the box to a wall. The box has a lid 22. A printed-circuit board 23 is mounted in the body of the box and has a block of screw terminals 24 mounted thereon. On the terminal face of board 23 there are terminal designations (shown in Figure 3) to indicate the individual wires which should be connected to the respective terminals. Cables from the system components are led into the box and the wires in the cables are connected to the respective terminals.The cable from the programmer is shown at 15a; that from the cylinder thermostat at 12a; that from the diverting valve at 14a; that from the room thermostat at 13a; that from the pump at 1 lea; and that from the boiler at 10a. The A.C. mains cable is shown at 1 6a and is connected to a fuse 26 and an on/off switch 27 mounted in the lid.

It will be seen that each incoming wire is connected to a clearly designated respective terminal.

The terminals are appropriately interconnected by copper strips printed on the reverse side of the board 23. Also, there are some soldered wire links on the rear of the board to provide the necessary crossover connections between appropriate parts of the printed-circuit. Alternatively the printed-circuit interconnections may be carried on both sides of a double-sided board with plated-through holes, the terminal designations then being carried on part of the front face unused for circuit connections.

Figure 3 shows the terminal designations on the front face of the board. These are produced in copper foil on the face of the board by a printedcircuit technique.

The circuit interconnections on the board correspond electrically with the circuit diagram of Figure 1.

It will be seen that with the arrangement described above, the procedure of connecting the central heating system is reduced, in accordance with the invention, to wiring the terminals of the central heating system components to the junction box terminals as designated in the junction box. It will be noted that there is provided a respective junction box terminal for each component terminal so that a simple one-to-one wiring is all that is necessary.

The invention is not restricted to the details of the embodiment described above with reference to the drawings. For example, the invention is applicable to other central heating systems. The board may be a printed-circuit board specifically designed for a particular system or may be of the "bread-board" kind which has parallel copper-foil strips which may be selectively broken and interconnected with wire to effect the pre-connection of the junction box terminals. Other kinds of proprietary "bread-boards" may equally well be used. The terminal designations may be painted or printed on the board or on a label stuck to the board or terminal block.

Claims

1. Ajunction boxfora central heating system, the junction box being provided with a set of terminals for connection to specific terminals of the components of the system; the junction box having markings which designate the junction box terminals with respect to the component terminals to which they should be connected; and a circuit board pre-connected to interconnect the junction boxterminals in the required manner.

2. Ajunction box as claimed in claim 1 wherein the circuit board is a printed-circuit board and at least some of the interconnections are printed-circuit connections.

3. Ajunction box as claimed in claim 1 or claim 2 wherein the junction box terminals are screw terminals mounted directly on the circuit board.

4. Ajunction box as claimed in any of the preceding claims wherein the junction box terminals are mounted on a front face of the board and the inter-connections are on the rear face, the said terminal designations being carried on the front face.

5. A junction box as claimed in claim 4 wherein the said terminal designations are made in copper foil by printed-circuit techniques.

6. A junction box substantially as hereinbefore described with reference to Figures 2 and 3 of the accompanying drawings.

7. A method of connecting a central heating system having a number of electrical components including temperature and time control units, the method consisting in taking a junction box as claimed in any of the preceding claims, wherein the terminal designations correspond to terminals of the components of the system, and connecting the junction box to the component terminals as designated.