Amperage measurements can be measured on insulated and bare conductors.An accurate current measurement does not require any direct contact with the line. However, Amperage cannot be measured when the conductor is shielded.
Hot-line Voltage measurements require bare conductors for readings. To take and accurate reading, the volt meter must make direct contact with the bare conductor. Measurements taken on conductors with insulation or shielding will not be able to take a reading.
POWER FACTOR MEASUREMENTS
To take an accurate power factor measurement, the meter's contactor must make direct contact with the bare conductor. Accurate power factor cannot be measured on any type of insulated or shielded conductors.
DIRECTION OF CURRENT FLOW
The direction of current flow can be measured on insulated and bare conductors. Direction of current flow cannot be determined on a shielded conductor or wire.
Micro-ohm measurements require direct contact of both the meter and contactor to a bare conductor. Measurement sets cannot be taken on any type of covered conductor.
TOTAL HARMONIC DISTORTION (THD) MEASUREMENTS
An accurate THD measurement does not require any direct contact with the line and may be taken on both insulated and bare conductors. THD measurements taken on shielded conductor will not take a reading.