Lake Shore 475, Руководство пользователя

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Lake Shore Model 475 Gaussmeter User’s Manual
Operation Peak Operation 4-21
4.8.2 Peak Operation Periodic/Pulse Setup
The Peak measurement mode can be configured to measure pulsed fields or the maximum amplitude of periodic fields.
In periodic mode, the instrument follows the peak amplitude of the periodic signal. This may be useful in determining
additional information about AC fields, such as crest factor. Pulsed fields with a minimum pulse width of 20 µs can be
captured using the pulse measurement mode. Once captured, these readings will only change if a larger peak is
measured, or if the
Reset key is pressed.
To setup the periodic or pulse feature,
press and hold the Peak key for approximately 4 seconds. The Peak configuration
screen appears as a prompt for selecting Periodic or Pulse measurements.
Sel ec t Wi t h ° ®
Pe a k Pe r i o d i c
Use the
s
or
t
key to select from Periodic or Pulse. Press Enter to accept the new selection and continue to the next
setting screen. Press Escape to cancel the new selection and return to the normal display.
4.8.3 Peak Operation Display Setting
Typically the positive peak reading (PK+) is displayed on the top line when in Peak measurement mode. Sometimes it
may be beneficial to display the negative peak reading (PK–) on the top line instead of the maximum. The user may also
display both peak readings, with the positive reading on the top line and the negative reading on the bottom line.
Displaying both will override the two line display configuration when Peak is active (refer to Paragraph 4.4.1).
To configure the Peak display setting, continue from the Periodic/Pulse selection screen or
press and hold Peak and then
press Enter until the following screen appears as a prompt for Peak display setup.
Sel ec t Wi t h ° ®
Pe a k Di s p PK+
Use the
s or t key to select PK+, PK-, or Both. Press Enter to accept the new selection and return to the normal
display. Press Escape to cancel the new selection and return to the normal display.
4.8.4 Peak Operation Reset
In Peak Measurement mode, the Reset key is used to clear any captured pulsed readings.
4.8.5 Peak Operation Frequency Measurement
In Peak measurement, the frequency is only measurable in Periodic mode. The frequency is calculated using a zero-
crossing counter. The frequency measurement is only valid for robust fields with a single, dominant frequency. Refer to
Paragraph 4.4.1 to configure the display for frequency.