21
Measurement Techniques
Understanding Measurement Currents
Insulation resistance is defined as the dc test voltage divided
by the total current flowing in an insulator. The total current
has four components; capacitive current, absorption current,
conductance current and leakage current.
In the case of dry insulation, conductance current may be
negligible and the leakage current may be low, in which case
the absorption current will dominate the total current
measured.
