Bartington Grad601, Руководство по эксплуатации

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BARTINGTON INSTRUMENTS
Page 28 of 61 OM1800/26
the controls are too far out of adjustment, the controls will be re-set automatically and the
procedure will be re-started, with the full-scale range set to 1000nT and the fields displayed with
a resolution of 1nT.
After completing the procedure with the range set to 1000nT, the instrument should be within the
normal starting range for the set-up procedure. The program will set the range back to 100nT
and re-start the procedure from the beginning.
If the program resets the controls and sets the range to 1000nT for a coarse adjustment, the
operator will see a
Please Wait
message in the upper line of the display and a series of dots
appearing in the lower line of the display. During this short time, no measurements are made
and the orientation of the gradiometer is unimportant. The operator will be aware that the
fields are displayed to a resolution of 1nT during the coarse setting. The coarse adjustment will
end with the operator facing north, and the new fine adjustment sequence will begin with the
operator facing north again.
A coarse adjustment may be required after attempting to set up the instrument in a high gradient
area. If the coarse adjustment is called a second time, a fault is indicated and the set-up routine
will end with the message
Coarse Error Sensor followed by the sensor number, 1 or 2.
Note:
If the set-up is attempted in a relatively high gradient or when some magnetic
interference is present, possibly from a poor set-up area or an operator wearing magnetic
material, the fine control may still reach the end of its adjustment. The set-up will continue
and the result may be acceptable but a warning message,
Fine control limit
, together with
the relevant sensor number will be displayed at the end.
Note:
Always check the set-up by selecting the
Scan
mode (see Scan Mode (Grid Mode) ) and
noting the field readings as the gradiometer is rotated so that the arrows on the sensors
point north, south, east and west over the set-up area. The results should all be close to
zero, within a range of
± 1nT. However, the result will depend on the gradients within the
setting up area.
Each gradiometer holds the adjustment settings in internal non-volatile memory. Adjustments
made during the above operations will be maintained until the next set-up operation.
16. Scan Mode (Grid Mode) / Run Mode (NMEA Mode)
In the Scan or Run mode, the gradiometer readings are continuously displayed but not saved to
memory. The operation is determined from the values shown in the
Set parameters
menu.
If the Audio option has been set to On , the audio output will vary with changes in magnetic
gradient. The audio
Volume
can be set to high or low.