The ground wire must be a three-phase short-circuit ground wire, not three-phase separate ground or single-phase ground.
After the line is verified but no voltage, the ground wire should be installed immediately and three-phase short circuit. The work shift work lot ends and the possibility of sending power to the outage line branch line (including the user) should be tested, hanging grounding wire. Hanging and removing the grounding wire should be carried out under supervision. With the blackout line can be installed only in the workplace near a grounding wire.