The earthing switch is used to interconnect and earth the phase and neutral conductors of an electrical installation to ensure the safety of personnel during servicing.

To achieve this function,it is recommended to have locking in earthed position by 3 padlocks ,and this can be achieved when:
1-the Earthing Switch must be in "connected" position in a chassis equipped with an earthing kit
2-the Earthing Switch must be in “ON” position.

Under these conditions, the installation is earthed.

So,When the Earthing Switch is locked in earthed position:
1-it cannot be moved to "disconnected" position (a shutter prevents insertion
of the racking handle)
2-it cannot be turned "OFF" (a shutter prevents access to the "OFF" pushbutton).

Released for:Schneider Electric South Africa