SAM-III Construction Manual
See last page for document and copyright information, File: SAM-III Magnetometer Construction.doc, Page 66
Ferromagnetic objects within the vicinity of the sensor generally do not cause problems if their location
is permanent and they do not become magnetized.
Bury the fixture in a shady area to prevent direct sunlight on the soil surface above the sensors. Do not
disturb foliage surrounding the sensor area and, if no foliage is present, consider planting shrubs and
bushes to shield the soil surface above the sensors from direct sunlight.
It is important to remember that the magnetic sensor will pick up any variation in the local magnetic
field including automobiles, trucks and trains moving in the area, ferromagnetic tools brought nearby
and other manmade magnetic disturbances.
Any movement of the sensor or movement of ferromagnetic materials in its vicinity will cause a
variation in the magnetic field measurements. Therefore, after any movement it usually is necessary to
re-zero the SAM processor by pressing the F3 function key (Reset). Alternately, let the magnetometer
run and it will re-zero itself within 24 hours.
Field Use
The SAM-III sensors have proven to be very robust in the field and have survived incorrect signal and
power connections and shock from being dropped. However, they should never be routinely treated
that way. The sensor is encapsulated in an epoxy-like compound, which can be cracked and broken.
Also, the pins are fairly fragile and if bent back and forth will break. Broken pins are not repairable.
