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12.6 Measuring resistance
Make sure that all objects that you wish to measure (including circuit
components, circuits and component parts) are disconnected and dis-
charged.
Follow the steps below to measure the resist-
ance
1. Set the function dial to
Ω
.
Æ
“Ω” will show on the display.
2. Plug the red lead into the
Ω
terminal and
the black lead into the
COM
terminal.
3. Check the measuring leads for continuity
by connecting both measuring probes to
one another. The multimeter should show
a resistance value of approx 0–0.5 Ω (in
-
herent resistance of the test leads).
Æ
For low-impedance measurements of <600 Ω, hold down the
REL
button for
approximately one second when the measuring probes are short circuited.
This ensures that the inherent resistance of the test leads does not affect the
resistance measurement. The display should show 0 Ω.
4. Connect the measuring probes to the object that you want to measure. The
measurement will be indicated on the display (provided that the object you are
measuring is not highly resistive or disconnected). Wait until the display stabi-
lises. This may take a few seconds for resistances greater than 1 MΩ.
Æ
“OL” (overload) indicates that the measuring range has been exceeded or
that the circuit is broken.
5. After taking a measurement, remove the leads from the measured object and
switch off the DMM.
When taking a resistance measurement, make sure that the points that
come into contact with the measuring prods are free from dirt, oil, solder
and other impurities. These substances may distort the measurement.
The
REL
button only works when a measured value is displayed. It can-
not be used when “OL” is displayed.
R
