Alignment Trim - Bartington PA1 Operation Manual

BARTINGTON DEFENCE & SPACE

5.1.3. Alignment trim

In order to compensate for any small alignment inaccuracy in the test magnetometer, two
measurements are made, in each axis, with the magnetometer being rotated about the
measurement axis by 180 degrees and the average of the two voltages taken. When working with
an AC field, the axis alignment trim control is adjusted until the reading is the same each time
the test magnetometer is rotated about the axis being aligned.
X axis alignment trim in Y axis
Feed a signal from the signal generator into the X axis. Monitor the Y axis output of the
calibration magnetometer. Initially adjust the trim control until a minimum is obtained. Then
rotate the test magnetometer through 180° about the Y axis. If a signal is found then adjust the
trim control until the same level is observed when the magnetometer is in the normal position
and rotated position.
X axis alignment trim in Z axis
Feed a signal from the signal generator into the X axis. Monitor the Z axis output of the
calibration magnetometer. Initially adjust the trim control until a minimum is obtained. Then
rotate the test magnetometer through 180° about the Z axis. If a signal is found then adjust the
trim control until the same level is observed when the magnetometer is in the normal position
and rotated position.
Y axis alignment trim in X axis
Feed a signal from the signal generator into the Y axis. Monitor the X axis output of the
calibration magnetometer. Initially adjust the trim control until a minimum is obtained. Then
rotate the test magnetometer through 180° about the X axis. If a signal is found then adjust the
trim control until the same level is observed when the magnetometer is in the normal position
and rotated position.
Y axis alignment trim in Z axis
Feed a signal from the signal generator into the Y axis. Monitor the Z axis output of the
calibration magnetometer. Initially adjust the trim control until a minimum is obtained. Then
rotate the test magnetometer through 180° about the Z axis. If a signal is found then adjust the
trim control until the same level is observed when the magnetometer is in the normal position
and rotated position.
Z axis alignment trim in X axis
Feed a signal from the signal generator into the Z axis. Monitor the X axis output of the
calibration magnetometer. Initially adjust the trim control until a minimum is obtained. Then
rotate the test magnetometer through 180° about the X axis. If a signal is found then adjust the
trim control until the same level is observed when the magnetometer is in the normal position
and rotated position.
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