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Copyrights 2000 – 2012, Analog Technologies, Inc. All Rights Reserved. Updated on 11/22/2012
4
Analog Technologies
VC480C
Multimeter
Principles
1. Refer to the following illustrations. There is a testing current going through the range from “I+” to “I
-
”.
2. This current is going through a resistor Rx (resistance value not know)
3. The voltage Vx can be measured on terminal Rx1/Rx2: Vx=Rx x Is, hence Rx=Vx/Is
4. The unknown resistance value can be calculated via Vx value, and will be displayed on the LCD.
5. To have an accurate resistance value, please make zero calibration before measurement.
Accurate Impedance Measurement:
1. Input the two connectors of the red test lead into the two red connectors of the instrument on the right side, and the two
connectors of the black test lead to the two black connectors of the instrument on the left side.
2. Tune the switch to a suitable range.
3. Clamp the two test clips on the 0 ohm circuit terminals, and adjust the zero knob to make the reading as 0.
4. Once a new range is selected, always do the zero calibration before measurement.
5. To measure an unknown resistor Rx, follow the following method as illustrated below:
6. To measure a resistor on a PCB, follow the following method as illustrated below:
7. The tested result will be displayed on the LCD.
Caution
1. If the tested resistance is over 2k
Ω
or there is open circuit, the LCD displays “1”.
2. When testing a live resistor, to ensure safety, do not proceed testing until the tested circuit is completely powered off and
all capacitors are fully discharged.
3. If testing results have considerable, it may be caused by other live components of the same circuit or by electric potential
on the two ends of the resistor.
4. Do not input voltage to the resistance range!
DATA HOLD
Press the “HOLD” button, the current data will be held on the LCD. Press the “HOLD” button again to cancel data hold.
Note:
There is no data hold function during insulation resistance measurement.
BACKLIT DISPLAY
Pressing “*” button, the LCD backlight turns on. Pressing “*” button again, the LCD backlight turns off.
SAFETY INSTRUCTIONS AND MAINTENANCE