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5.4 CAPACITANCE(C) MEASURING PROCE DURE
(1) Press the POWER button to turn the power on
(2) Select the range switch for the maximum expected capacitance.
(3) Fully discharge any capacitors.
(4) Connect the alligator clips to the capacitor leads.
(5) Read the display. The value is direct reading in the electric al unit
(nF, uF) indicated at the selected range switch. If DISPLAY show
“1”, It indicate on Out-of-Range measurement. If the display
indicates one or more leading zeros, shift to the next lower range
scale to improve the resolution of the measurement.
NOTE:
(a)
If the capacitance value is unmarked, start from the 2nF range
and keep increasing until the over-range indication goes off and a
reading is obtained.
(b)
A shorted capacitor will read over-range on all ranges. A
capacitance with low voltage leakage will r ead over range, or a
much higher value than normal.
An open capacitor will read zero on all ranges (possible a few pF
on 2nF range, due to stray capacitance of the instrument).
(c)
Very low capacitance measurement should be performed by using
extremely short leads in order to avoid introducing any stray
inductance
(d)
When using the optioned test leads, remember that the leads
introduce a measurable capacitance to the measurement. As a
first approximation, the test capacitance did measured by opening
the leads at the trips, recording the open circuit value and
subtracting the value.
(e)
Capacitors, especially electrolytic, often have notoriously wide
tolerances. Do not be surprised if the measured value is greater
than the value marked on the capacitor, unless it is a close
tolerance type. However, value is seldom drastically below the
rated value.
