33
_______________________________________________________
2.4 Frequency Measurement
_______________________________________________________
NOTE
5. Switch between the auto range and the manual range
as necessary.
6. Attach or remove the rigid insulating sleeve as
required by the measurement category.
7. Carefully contact the test leads to a circuit.
Be sure to use the test leads with the sleeves
attached when performing measurements in the CAT
III measurement category. In a CAT II environment,
if the tips of the test leads do not reach the
measurement object, remove the rigid insulating
sleeve before measuring.
At the 100 Hz and 1000 Hz ranges,
----
appears on
the counter when the frequency is lower than 10 Hz.
----
appears on the counter, if the frequency is lower
than 1 Hz.
O. L.
appears on the counter, if the frequency is
higher than 1 kHz.
If an input value is significantly lower than the
range, on accurate measurement may not be
achieved, resulting in
----
,
O. L.
or display
fluctuations.
The 10 Hz range or 100 Hz range will display up to
125% of each range, however, only the range from
10% to 100% can be displayed with guaranteed
accuracy.
The frequencies, whose waveforms are special such
as inverters, would not be measurable, when the
carrier frequencies are lower than several kHz.
Full-wave rectification indicates twice the actual
value, due to an AC coupling in the internal circuit.
It would take time to stabilize the counter,
depending on the frequency range or the input
frequency.
Summary of Contents for 3285-20
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