Operation Manual

GMC-I Messtechnik GmbH 49
I
PE
PELeakage Current
Application
Measurement of protective conductor current may be performed
in the case of safety class I devices for which it cannot be assured
that all components exposed to line voltage are tested by means
of insulation resistance measurement, or if insulation resistance
measurement cannot be performed for other reasons.
Definition of Differential Current
Sum of instantaneous current values which flow via the L and N
conductors at the device mains connection. Differential current is
practically identical to fault current in the event of an error. Fault
current: Current which is caused by an insulation defect, and
which flows via the defective point.
Definition of Equivalent Measurement
Equivalent leakage current is current which flows through active
conductors of the device which are connected to each other (L/N)
to the protective conductor (SC1), or to exposed, conductive
parts (SC2).
Definition of Protective Conductor Current (direct measurement)
Current which flows through the protective conductor with
housings which are isolated from ground.
Differential Current Measuring Method
The device under test is operated with mains power. The sum of
the momentary values of all currents which flow through all active
conductors (L/N) at the mains side of the device connection is
measured. The measurements must be performed with mains
plug polarity in both directions.
Equivalent Measurement Method
A high-impedance power supply is connected between the
short-circuited mains terminals and all exposed metal parts of the
housing (which are connected to one another).
Current which flows over the insulation at the device under test is
measured.
Protective Conductor Current Measuring Method (direct measurement)
The device under test is operated with mains power. Current
which flows through the PE conductor to earth at the mains side
of the device connection is measured.