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2.2 Current Measurement
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NOTE
When 0 is displayed after zero adjustment, the
measurement can be performed without the
interference of the count remaining immediately after
the power is turned on.
4. If the counter fails to become zero under no input,
press
HOLD
button and then press
0ADJ/RESET
button to perform a zero-cancel correction.
5. Open the top ends of the clamp core and clamp the
measured conductor so that it passes through the
center of the clamp core.
Just after suspension of input, or when modes are
switched under no input, the counter would not
become zero for about 10 seconds. This is normal
and simply reflects the workings of the internal
circuit. But you can measure with guaranteed
accuracy before the counter becomes zero.
Depending on ambient temperatures, the counter
would not become zero under no input. If this
happens, preform a zero-cancel correction (See
3.1.2: Zero-Cancel Correction Function).
The polarity of the input is not displayed, even if
DC current is measured in this mode. If the clamp
sensor is reoriented, the measured values may
change, but the values are within the guaranteed
accuracy. (In case that you would like to measure a
DC current which doesn't have AC components, you
should make the measurement in DC A mode.)
During a f.s. input, the measurement response speed
is about 250 ms during rise (0% to 90%) and about
500 ms (100% to 10%) during fall (See 2.2.2
Measuring AC Current (AC A), Figs. 1 and 2).
The 200 A range will display up to 250 A, however,
only the range from 10 A to 200 A can be displayed
with guaranteed accuracy.
Summary of Contents for 3285-20
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