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9.3 AC 4-terminal Measurement Method
The instrument uses AC four-terminal measurement method, so when measuring resistance,
it is not necessary to consider the internal resistance of the test line and the contact
resistance between the test line and the object under test.
The AC current (Is) flowing from the SOURCE port of the instrument flows through the
tested battery. The voltage drop (VIS) of the internal resistance of the battery is measured
by the SENSE port. At this point, since the SENSE port is connected to an internal voltmeter
with a high impedance, there is no current passing on the R2 and R3 representing the
resistance and contact resistance in the test line. Therefore, there is no voltage drop on
the resistance R2 and R3, because the voltage drop of the resistance and contact
resistance in the test line is very small, which can be ignored. In the instrument, using a
synchronous detection system, the internal resistance is divided into impedance and
reactance, showing only the actual part.
if the resistance within the test line, the contact resistance between the object under test
and the test line or the contact resistance between the test line and the instrument
increases, then the instrument will be supplied to the abnormal current of the object
under test, which will cause the test state error, showing the "------" symbol where the
resistance is tested.
INFORMATION ON WASTE DISPOSAL FOR CONSUMERS OF ELECTRICAL & ELECTRONIC EQUIPMENT.
When this product has reached the end of its life it must be treated as Waste Electrical & Electronics
Equipment (WEEE). Any WEEE marked products must not be mixed with general household waste, but
kept separate for the treatment, recovery and recycling of the materials used. Contact your local authority
for details of recycling schemes in your area.
Made in China
LS12 2QQ