Hioki 3290-10, Инструкция по эксплуатации

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4.3 Measuring Current
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M
easurement
P
ro
cedure
Range Selection
2.
Press the button to select the range.
For Current Measurement
For Frequency Measurement
AUTO
AUTO Ranging
When using the 9691 or 9692 : 20.00 A/ 200.0 A
When using the 9693 : 200.0 A/ 2000 A
L
L (Low) Range
When using the 9691 or 9692 : 20.00 A
When using the 9693 : 200.0 A
H
H (High) Range
When using the 9691 or 9692 : 200.0 A
When using the 9693 : 2000 A
• When measuring only current (so that no output settings are
needed), AUTO ranging can be used, but if the range is
exceeded during current integral or duty measurement, correct
measurements cannot be obtained.
• If you press the or button after AUTO ranging is
selected, the range that is active at setting time becomes the
fixed range (the L range if nothing is being measured).
• When selecting a range, both rms and peak values need to be
considered. For example, if the rms current is low but the peak
value is high, the waveform may be clipped (depending on the
range). The figure below left shows a waveform that can be
measured in the H range (200 A range). The waveform is not
clipped, so the measured value is 20 A. On the other hand, the
figure below right shows clipping at 50 A because of the 2.5
crest factor limitation (50 A in the case of the 20 A range). The
(incorrectly) measured value in this case is 10 A, and correct
measurement is not performed (crest factor is the peak value /
range rating).
Peak value
L range H range
Measured
value
Measured
value
Peak value 100 A
20 A
0 A
0 A
10 A
50 A
AUTO
AUTO Ranging
Internal ranges 10.00, 100.0 and 1000 Hz
The current range does not need to be set.
The range switches upward at 1250 counts, and downward at
100 counts.
Example: 12.50 Hz
→
12.6 Hz, 10.0 Hz
→
9.99 Hz