DESCRIPTION OF THE INVENTION According to the invention, there is provided a telephone line testing and protection device, which includes 10 a first connector for connection to a telephone line ; a second connector for connection to a PABX line ; a lightning protection unit interconnected between the first and second connector, characterised thereby that the device further includes a first switch between the first connector and the lightning protection unit for disconnecting the lightning protection unit from the first connector.

It will be appreciated that the device is engageable, in use, with a rack that has complementary connectors.

20 The device may have a second switch between the second connector and the lightning protection unit for disconnecting the lightning protection unit from the second connector.

The device may include a socket to which telephone testing equipment may be connected, the socket being connected to the first switch, to be connectable to the first connector when the lightning protection unit is disconnected therefrom. Instead, or in addition, the device may have a socket that is connected to the second switch to be connectable to the second connector when the lightning protection unit is disconnected therefrom.

The device may also include a line tester that is connectable to the first connector via a third switch. The third switch may be connected directly to the first 10 connector or via the first switch.

In a preferred embodiment, the first and second switches may be operable in unison, and the device then has a pair of sockets, one connected to the first switch and the other connected to the second switch.

The switches may be spring loaded or bistable.

Those skilled in the art will appreciate that the device may have a pair of first connectors and a pair of second connectors, and the or each switch will then have two 2 0 contactors that are switched in unison.

A plug may also be provided, for use with the embodiment that has a pair of sockets, whereby the lightning protection unit may be bridged out.

The device may include a plurality of modules, each module having a first and second connector, a first and second switch and a lightning protection unit, and may have one pair of sockets, a first socket of the pair being connected to all the first switches and a second socket of the pair being connected to all the second switches.

Such a multi module device may further include a line testing device connected to all the first switches by means of the third switch.

10 The device may have a housing, in which the or each lightning protection unit and the or each switch is housed, the or each switch having an operating member that is externally accessible and with the first and second connectors being external thereto.

BRIEF DESCRIPTION OF THE ACCOMPANYING ILLUSTRATIONS The invention will now be described, with reference to the accompanying drawings, in which Figure 1 shows a circuit diagram of a first embodiment of a device in 2 0 accordance with the invention; Figure 2 shows a circuit diagram of a second embodiment of the invention, illustrating its connection, in use, to a telephone exchange and to a PABX; Figure 3 shows schematically a multi-module version of the second

embodiment; and Figure 4 shows a schematic three dimensional view of the device of Figure 3.

Referring to Figure 1, shown therein is a first embodiment of a device in accordance with the invention, for testing a telephone line and protecting equipment connected to it, which is designated generally by reference numeral 10.

The device 10 has a lightning protection unit ("LPU") 12, a first connector 14, a second connector 16, a first normally closed push button switch 18, a second normally closed push button switch 20, and a socket 22. The first switch 18 is connected between the LPU 12 and the first connector 14 and the second switch 20 is connected between the LPU 12 and the second connector 16. The socket 22 is connected to both the normally open terminals of the switches 18 and 20. In use, the first connector 14 is connected, via a complementary connector (not shown) to a telephone line and the second connector 16, via a further complementary connector (also not shown) to a line leading to a PABX. Conventional telephone testing equipment (not shown) is connectable to the socket 22. Thus, if there is a fault and a technician suspects that the telephone line is faulty, he connects his testing equipment to the socket 22 and closes the first switch 18. If the equipment detects that the telephone line is faulty, then the technician knows that the telephone line is the problem and attends thereto. If the telephone line is not faulty, then the technician tests the LPU 12, by releasing the first switch 18 and closing the second switch 20. If the equipment again does not detect a fault, then the technician knows that the fault is not in the telephone network or the LPU and must be in the PABX. Clearly if the equipment detects a fault then the LPU is faulty and the device 10 is replaced.

Referring to Figure 2, a second embodiment of a telephone line testing and protection device is referred to generally by reference numeral 22. In the drawing, a two wire system is shown, rather than the schematic single wire depiction in Figure 1.

This device 22 has an LPU 12, a first set of connectors 14, a second set of connectors 16, a first double pole ON/OFF normally closed switch 24, a second double pole ON/OFF normally closed switch 26, a first socket 28, a second socket 30, a third 10 double pole, normally open push button switch 32 and a line tester 34. The first and second switches 24 and 26 are operated in unison, by a single operating member, which is not shown in Figure 2.

As shown, the first switch 24 is connected between the first set of connectors 14 and the LPU 12 and to the first socket 28 and the third switch 32. The second switch 26 is connected between the LPU 12 and the second set of connectors 16 and to the second socket 30. The third switch 32 is also connected to the line tester 34.

Also shown in Figure 2 is a telephone exchange 36 that is connected to a set of 20 connectors 38, by telephone lines 40, that are complementary to the set of connectors 14 and which engage one another, in use; and a PABX 42 connected to a set of connectors 44, by PABX lines 46, the connectors 16 and 44 being complementary and engageable, in use.

In use, to test the telephone line 40 and the LPU 12, the switches 24 and 26 are operated, to connect the connectors 14 to the socket 28 and the connectors 16 to the socket 30. The testing equipment is plugged into the socket 28 and if a fault is detected, then the telephone line 40 is faulty. If there is no fault, the equipment is plugged into the socket 30. If a fault is then detected, then the PABX line 46, or the PABX, is faulty. If no fault is detected, then the LPU 12 is faulty and the device 22 is replaced. As a temporary measure, if the LPU 12 is faulty, then a bridging plug 48 is plugged into the sockets 28 and 30 and the switches 24 and 26 are left ON, until such 10 time as the device 22 is replaced. Instead of using the testing equipment, the switch 32 could be closed, whilst the switches 24 and 26 are ON, to connect the line tester 34 to the telephone lines 40 and test them.

Referring now to Figure 3, a multi module device 50 is shown. This device 50 has a number of LPU's 12.1 to 12. n, each with its own switches 24 and 26, such that there are the same number of switches 24.1 to 24. n and 26.1 to 26. n as there are LPU's. Correspondingly, the device 50 has a number of first connectors 14.1 to 14. n and second connectors 16.1 to 16. n that are respectively connected to the switches 24 and 26. It will be noted that there is only one socket 28 and one socket 30, that are 20 respectively connected to all the switches 24.1 to 24. n and 26.1 to 26. n. Similarly, there is only one switch 32 and line tester 34. With this multi module embodiment, the line and LPU to be tested are selected by operating the appropriate switches 24 and 26.

A three dimensional representation of a ten module device 50 is shown in Figure 4. As shown, the device has a housing 54 in which the various components are housed, with spade connectors 14 and 16 being located on an external strip 56.

Operating members 58.1 to 58.10 for the switches 24 and 26 protrude through openings in a face of the housing 54, as well as a reset button 60 for resetting the switches 24 and 26. The face of the housing 54 also has an aperture 62 through. which the sockets 28 and 30 are accessible and a lamp 64 (which is not shown in Figures 2 and 3). Finally, a button 66 for the switch 32 protrudes through a side wall of 10 the housing 54.