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f) Measuring resistance
Make sure that all objects that you wish to measure (including circuit components, circuits and
component parts) are disconnected and discharged.
Follow the steps below to measure the resistance:
•
Turn on the DMM and select the “Ω” measurement mode.
•
Plug the red lead into the Ω terminal (K) and the black lead into the COM
terminal (I).
• 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 (inherent resistance of the test leads).
• For low-impedance measurements (<400 Ohm), press the “REL” button to
discount the inherent impedance of the test leads in the subsequent resist-
ance measurement. “REL” will appear on the display and the main display
will show 0 Ohm. Automatic range selection (AUTO) is now disabled. For
all other measurements, the inherent resistance of the test leads is negligi-
ble. Press the “REL” button again to disable the reference value function.
Automatic range selection is now enabled.
• 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 stabilises. This may take a few seconds for resistances greater
than 1 MΩ.
• “OL” (overload) indicates that the measuring range has been exceeded or
that the circuit is broken.
• 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 measur-
ing prods are free from dirt, oil, solder and other impurities. These substances may distort the measure-
ment.
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