Mini SWER & Pole Tester Hazards & Risks

Power LIne TreeWhen using the unit on power lines where lower voltages e.g. 415 volts lines are below higher voltage power lines, an affect will occur where a null or dead zone may appear.

Solution: To overcome this move out from under the line parallel or adjacent until a signal is heard and repeat procedures 1 to 16.

Power line tree interferanceElectric fields from power lines can be disturbed and redirected by objects that are grounded. A tree near a power line will lower the strength of an electric field which causes you to change the setting on your tester. Other influences such as weather, water (humidity) will change the electric field strength.

Pole mounted transformers cause null effects when stepping down voltage shown here 11kV to 415 volts the surface area is greater therefore a stronger signal is generated.Pole mounted Transformer

Solution: By moving around the pole at a distance of 10 metres a clear and free signal can be gained.


The Modiewark tester is not designed to operate where mains cable are armoured, enclosed in metal conduit, underground or any situation where the AC field is negated by metal shielding.
The unit will not detect DC voltages and must be used by trained personnel around train tracks and railway control boxes and signals.