Lake Shore 475, Руководство пользователя

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Lake Shore Model 475 Gaussmeter User’s Manual
Operation DC Operation 4-7
Selecting the range this way will disable the Auto Range function. To enable the Auto Range function, press Autorange .
The autorange setup screen appears as a prompt for turning the Auto Range function on or off.
Sel ec t Wi t h ° ®
Au t o Ra n g e Of f
Use the s or t key to select from Off or On. 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.
4.6.2 DC Operation Resolution and Filtering
The firmware linear filter is an integral part of the Model 475 DC measurement. It is directly related to measurement
resolution, frequency response, and reading rate. The higher reading rates are only available over the computer interface,
but the display will update at 5 readings per second independent of filter configuration.
The resolution can be set from 3¾ to 5¾ digits. The table below shows how the resolution is related to the reading rate
and the frequency response.
Display Setting Number of Digits 3 dB Frequency Maximum Reading Rate
3 3 ¾ 100 Hz 100 – 1000 readings/second*
4 4 ¾ 10 Hz 30 readings/second
5 5 ¾ 1 Hz 10 readings/second
* Limited Feature set, Interface dependent
To configure the resolution,
press and hold the DC key for approximately 4 seconds. The following screen appears as a
prompt for DC resolution setting.
Sel ec t Wi t h ° ®
Re s o l u t i o n 3 Di g i t s
Use the s or t key to select from 3, 4, or 5 digits. 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.
4.6.3 DC Operation Zero Probe
The zero probe function cancels out the zero offset of the probe or small DC magnetic fields. It is normally used in
conjunction with the zero gauss chamber, but may also be used with an unshielded probe (registering Earth's local
magnetic field). The zero probe function should be used any time a probe is changed, when operating conditions such as
temperature change significantly, and periodically during normal use. To cancel large magnetic fields, use the Relative
function.
NOTE: For best results, allow the instrument and probe to warm up for at least 5 minutes before zeroing
the probe, and at least 30 minutes for rated accuracy. The probe and the zero gauss chamber
should be at the same temperature.