Geometrics Memory-Mag G-856AX, Руководство по эксплуатации

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Geometrics, Inc
.
G-856AX Operation Manual
5
Magnetometer Set-up
The standard G-856AX system is used as a mobile instrument for measurement of the
magnetic field intensity sequentially at discrete locations. With the appropriate
accessories the standard system can be configured for measurement of the differential
magnetic field (gradient) over the survey area or the magnetometer can be set up to
record the temporal changes in the magnetic field intensity at a fixed point to acquire
base station measurements.
Sensor fluids
The sensor contains coils of insulated wire and for optimum operation these coils must be
submerged in a hydrogen-rich fluid. The following section provides information about
this fluid and the correct procedure for filling the sensor with fluid.
It is important that you DO NOT operate the sensor for an extended period without
fluid as this can damage the sensor.
The sensor should be filled so that the fluid level is
about 1cm below the fill port. There is a fill port tube inside the sensor that provides for
an air gap when the sensor is filled. Correct fluid level can be checked approximately by
shaking the sensor and judging the fluid level by the degree of sloshing. A more accurate
level check requires removal of the sensor’s fill plug and visual inspection of the
contents. If the sensor is empty or needs filling proceed as follows:
A. Place the sensor on a flat, level surface.
B. Remove the blue cap plug on the sensor. Observe that the fill-port is a threaded
tube extending into the sensor vessel. This design provides a 1cm air gap that
allows for thermal expansion of the sensor fluid.
C. Fill with acceptable sensor fluid to within 1 cm. from the top. Acceptable fluids
for proton-precession magnetometers include:

Shell SOL-71 (Shell Oil Co. product).

Charcoal Lighter Fluid (Kingsford, Wizard, etc.)

n-Decane (chemical supply houses, oil refineries)

ISOPAR-1 (Exxon Oil Co. product)

Odorless Mineral Spirits (also known as Naptha)

Kerosene
D.
Pour only clear fluid into the sensor. If fluid is dirty use a paper coffee filter or
fine screen to eliminate particles.
E. Slowly pour fluid into sensor until it is full. The sensor is full when the fluid just reaches
the bottom of the fill-port as described above.
F.
Place Teflon

tape around the fill plug then screw it into the fill-port and tighten. Note:
the fill plug and fill-port have tapered threads designed to form a tight seal. Tighten the
plug just enough to prevent leakage - over tightening may crack or damage the sensor
housing.
G.
Sensor is now ready for use.