AN EARTHING SWITCH
FIG1 shows a schematic representation of an example of an earthing switch
FIG1 shows an example of an earthing switch 10, where optional features are shown in dashed form. The earthing switch 10 comprises a housing 20, a connector 30, a movable contact 45 and an earth terminal 40. The housing 20 is configured to form an insulating shell of the earthing switch 10. The connector 30 is configured to connect to a Medium Voltage MV cable 70. The connector 30 is configured also to enable an electrical connection 50 to a core 80 of the MV cable 70 to extend at least partially through the connector 30. The electrical connection 50 can be the core 80 of the MV cable itself or a separate conductor to which the core 80 of the MV cable 70 is connected. The connector 30 is configured also to enable an outer layer 90 of the MV cable 70 to extend at least partially over the connector 30. The earth terminal 40 extends through the housing 20, and a part of the earth terminal 40 that is external to the insulating shell is configured to electrically connect to Earth potential. When the MV cable 70 is connected to the earthing switch 10, the earthing switch 10 is configured to operate in two modes. In a first mode of operation the electrical connection 50 that extends at least partially through the connector 30 is not connected to a part of the earth terminal 40 internal to the insulating shell. This means that the earthing switch 10 is open and the core 50 of the MV cable 70 is insulated from Earth potential. In a second mode of operation the electrical connection 50 that extends at least partially through the connector 30 is connected to the part of the earth terminal 40 internal to the insulating shell. This means that the earthing switch is closed and the core 50 of the MV cable 70 is electrically connected to Earth potential. The position of the movable contact 45 inside the earthing switch defines the present mode of operation.
schematic
150
extending step
30
connector
160
extending
130
extending step
45
movable contact
20
housing
40
terminal
10
earthing switch
50
contact
140
extending step
110
forming step
60
outer layer
170
electrically connecting
120
connecting step
['15. A method (100) of providing an earthing switch, comprising: a) forming (110) an insulating shell of a housing (20) of an earthing switch (10); c) connecting (120) a Medium Voltage MV cable (70) to a connector (30) of the earthing switch; d) extending (130) an electrical connection (50) that is connected to a core (50, 80) of the MV cable at least partially through the connector; e) extending (140) an outer layer (90) of the MV cable at least partially over the connector; g) extending (150) an earthed terminal (40) through the housing,wherein a part of the earthed terminal that is external to the insulating shell is electrically connect to Earth potential; and wherein a movable contact (45) that is inside the earthing switch is electrically connected to the earthed terminal, and wherein the method of providing an earthing switch comprises two modes of operation: • in a first mode of operation the electrical connection to the core of the MV cable that extends at least partially through the connector is not connected to the movable contact internal to the insulating shell to insulate the core of the MV cable from Earth potential; and • in a second mode of operation the electrical connection to the core of the MV cable that extends at least partially through the connector is connected to the movable contact internal to the insulating shell to electrically connect the core of the MV cable to Earth potential.']