Full Product Manual

13
Test Frequency Functions
Test frequency can greatly affect the results of measurement readings,
especially when measuring inductors and capacitors. This section provides
some recommendations and suggestions to consider.
Capacitance
When measuring capacitance, selecting the right frequency is important
in obtaining the most accurate results. Generally a 1kHz test frequency is
used to measure capacitors that are 0.01μF or smaller. For capacitors that
are 10μF or larger, a lower frequency of 120Hz is used. Following this trend,
high-test frequencies are best for testing very low capacitance components.
For large capacitance components, low frequency would be optimal.
For example, if the capacitance of the component is in the mF range, then
selecting 100Hz or 120Hz for the test frequency would give more accurate
results. The results will also be obvious because if the same component
was tested with 1kHz or 10kHz, the measured readings may look erroneous
on the display. In all cases, it is best to check with the manufacturer's data
sheet in order to determine the best test frequency to use for measurement.
Inductance
Typically a 1kHz or 10kHz test frequency is used to measure inductors
that are used in audio and RF circuits because these components operate
at higher frequencies. However, a 120Hz test signal is used to measure
inductors that are used for applications such as lter chokes in power
supplies, which are typically operated at 60Hz AC (in US) with 120Hz
lter frequencies. In general, inductors below 2 mH should be measured
at 1kHz frequency while inductors above 200H should be measured at
120Hz. In all cases, it is best to check with the manufacturer's data sheet
in order to determine the best test frequency to use for measurement.
Selecting Test Frequency
The meter has ve test frequencies: 100Hz/120Hz/1kHz/10kHz/100kHz. Press
the FREQ button to scroll through the ve frequencies sequentially.
Note: The test frequency can affect the accuracy of the results depending
on what frequency is selected as well as what type and value of component
is being measured or tested.
continued...
REED Instruments
1-877-849-2127 | [e-mail] | www.reedinstruments.com