What is megger and how does it work?

Purpose: The megger tests the integrity of the insulation between conductors that run side by side and do not physically meet or connect. Meggers or Mega-ohm testers also are typically used to test the dielectric in coaxial cable. Meggers are used to test the insulation of buried cables by placing a lead to earth ground and one lead to the outer conductor of a coax cable or any or all conductors of multiple (more than one) buried wires. Method: introduce a high enough voltage to the conductors eventually the current will travel betwen the conductors. Read the indicator to see the amount of resistence to current flow on the meter indicator. the reading will generally be in millions of Ohms (megohms)