Measurement principles – GW Instek GLC-9000 User Manual User Manual
Page 15

OVERVIEW
15
5. Patient
Leakage
Current III
Refers to the current that flows through a human
body that is directly connected to a device that
malfunctions.
(Medical Equipment)
6. Patient
Auxiliary
Current
Refers to the current that flows through a human
and a device during normal operation. This is not
intended to be perceptive. (Medical Equipment)
Measurement Principles
Background
Leakage current can be categorized into 3 types:
Electric current that flows through the body of
someone who touches the equipment, the current that
flows through a protective grounding wire to earth and
the current that flows through a human body
connected to an applied part. When testing the
leakage current of an EUT (equipment under test),
testing must be performed under normal and single
fault conditions.
As shown below, a number of relays are used to
simulate different fault conditions. Power to the EUT
is normally open and thus turning off the power
disconnects one wire on the power line.