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3.7 INRUSH function
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Description
This function is used to follow quick changes in the current,
such as a damped sinusoidal quantity, by measuring the
successive rms values calculated on ½, 1, 2½, 5 and 10
periods from the largest rms value computed and updated
on ½ period.
The applications are:
- Measurement of motor start-up currents
- Correct definition of fuses and circuit breakers (signal
amplitude-time relationship)
- Stress on components by current overload
The field of application is limited to industrial frequencies
(15 Hz... 70 Hz)
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Implementation
This function is accessible in AC or AC + DC current
measurement, after selection of the MIN/MAX mode.
Action
Display
Comments
Press
0.5 P then the value
the key
for rms
Enter the function
yellow
corresponding
out F
Signal frequency
< 15 Hz or > 70 Hz
Press on
1P-2,5P-5P-10P-0,5P
HOLD key
↑
Consultation of values
then press
with each time
rms (computed on
successively
the rms value
of consecutive periods )
the yellow
corresponding
key
alternately
Short pressure Return to values
Exit from the function
on the
MIN, MAX or PEAK
return to MIN/MAX mode
MIN/MAX key
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Characteristics
- Accuracy: 5% +0.5 A
- Capture time: 10 periods of the signal frequency (200 ms
at 50 Hz)
- Range for use:
≥
5 A peak for the first period of the signal
3.8 Frequency measurements (Hz)
This function is active only for the A and V functions in AC
(AC or AC + DC ) mode.
1. Perform a short pressing on the Hz key, the display shows
the frequency of the measured signal.
2. Pressing again returns to the previously displayed
measurement.
