Hioki CHT3548, User Manual, Page: 77 / 81

Hope Electronics Technology Manual
Edition
V1.0 77
Appx. 3 on DC mode and AC mode
There are two resistance measurement (or impedance measurement) types:
DC and AC.
l
DC type
Resistance meters CHT3540
，
CHT3548.
Common digital multimeters.
Common insulation testers.
l
AC type
Battery Testers CHT3560
，
CHT3563
，
CHT3554.
Common LCR meters.
DC resistance meters are widely used for measurement of general-purpose
resistors, winding resistance, contact resistance, insulation resistance, etc. The
DC type consists of an DC power supply and DC voltmeter. While its simple
circuitry makes it easier to increase accuracy, it is prone to measurement errors
due to electromotive force that may be present in the measurement path.
The AC type is used where measurement with direct current is not possible,
including measurement of inductors, capacitors, and battery impedance.
Essentially, an AC resistance meter is not affected by DC electromotive force,
because it consists of an AC power supply and AC voltmeter. However, it is
important to note that an AC resistance meter may indicate a different
measurement value from a DC one, for example, due to an iron loss included in
the series equivalent resistance of a coil.