This Article is about how the Fluke -1507 performs an Insulation Test.
The Fluke-1507 design is to source a voltage and current between two points and measure the voltage leaking between those two points.
If the voltage level leaking is zero volts the Insulation resistance results will show 11G ohms if the voltage source is 1000V.
If there is voltage leaking between the two points the more voltage leaking between the two points the lower the resistance the Fluke-1507 will display.
The rule of thumb for an Insulation Test to show a passing level is greater than 1M ohm, the higher the resistance the lower amount of voltage leaking between the two points.