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Manual Documentation Number M3640D1598
B&B Electronics -- PO Box 1040 -- Ottawa, IL 61350
PH (815) 433-5100 -- FAX (815) 433-5104
6-4. Measuring Resistance
WARNING: NEVER CONNECT THE TEST PROBES TO A SOURCE
OF VOLTAGE WHEN YOU HAVE SELECTED THE OHMS
FUNCTION AND PLUGGED THE PROBES INTO V/
Ω
TERMINAL.
BE SURE THAT THE CIRCUIT UNDER TEST HAS ALL POWER
REMOVED AND THAT ANY ASSOCIATED CAPACITORS ARE
FULLY DISCHARGED BEFORE YOU MAKE A RESISTANCE
MEASUREMENT.
Follow these steps to measure resistance:
1. Set the rotary switch to any of 200 Ohm to 2000 Mohm with 7 steps
(for Model M-3610D/3630D/3650D) or 200 to 20 Mohm with 6 steps
(for Model M-3640D/3650D)
2. Connect the test Ieads to the device you want to measure.
Notes:
•
The resistance in the test leads can diminish accuracy on the lowest
(200-ohm) range. The error is usually 1 to 0.2 ohms for a standard pair
of test leads. To determine the error, short the test leads together and
read the resistance of the leads.
•
When measuring resistance, be sure that the contact between the probes
and the circuit is good. Dirt, oil, solder flux, or other foreign matter
seriously affect resistance.
•
If the measured resistance value exceeds the maximum value, OL
displays to indicate overload and the bar graph flashes.
•
For resistance of approximately 1 Megaohm and above, the display
might take a few seconds to stabilize. This is normal for high resistance
readings.
