F.W. Bell 8000 series, Инструкция по эксплуатации

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F.W. BELL 8000 Series Gauss/Tesla Meter Instruction Manual
Section 6 – Flux Density Measurement 6-13
Hold Function
In some applications it may be desirable to “hold” a reading that is either
greater than (MAX hold) or less than (MIN hold) all previous readings. Also,
it may be necessary to capture the high (, Hold) and low (VALLEY Hold)
extremes of rapidly changing pulses. The hold functions will hold their
readings until reset by the user.
MIN and MAX HOLD General Description
The MIN and MAX hold functions are useful in determining the maximum or
minimum value of magnetic readings that occur over a period of time. The
MIN and MAX use readings that are arithmetically averaged by the meter for
slow changing signals.
The MAX hold function holds any reading that is arithmetically greater than
all previous readings. For instance, a reading of +125.0 is greater than
+99.0 or –150.0.
The MIN hold function holds any reading that is arithmetically less than all
previous readings. For instance, a reading of -125.0 is less than -99.0 or
+150.0.
PEAK and VALLEY HOLD General Description
PEAK and VALLEY hold modes are used to track rapid events such as
magnetizing pulses. Unlike MIN and MAX, PEAK and VALLEY are not
arithmetically averaged by the meter. They represent the instantaneous
extremes of a flux density waveform as they have been captured, within the
bandwidth of the meter.
In AC mode the analog filter selection will also affect the peak and valley
hold operation such that lowering the bandwidth and by extension the
sampling rate, will limit the meters ability to capture rapidly changing
signals. For transient or burst type signals which prevent the meter from
determining a fundamental frequency, selecting No Corrections in the AC
Freq Setup menu may provide better results.
Numerically, The PEAK hold function holds its reading the same as the
MAX hold function. The PEAK hold function holds the reading greater than
all previous readings, within the response time of the instrument. For
instance, a reading of +125.0 is greater than +99.0 or –150.0.
Numerically, The VALLEY hold function holds its reading the same as the
MIN hold function. The VALLEY hold function holds the reading that is
lower than all previous readings, within the response time of the instrument.
For instance, a reading of -125.0 is less than -99.0 or +150.0.
Note: Peak and Valley Hold functions are not available for the Vector Sum
display. (8030 Only)