SAM-III Construction Manual
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X: -82000/_____0Hz
Y: -82000/_____0Hz
Z: -82000/_____0Hz
When the sensors are connected and power is applied to the processor module, the display will show
magnetic field induction values (in nT) after a moment and will look similar to below. The actual values
are not important and will depend on the local environment and orientation of the sensors. For testing
purposes, it is only necessary that the sensors display a value other than the default –82,000 nT. If one
or two sensors are connected, only those fields will show magnetic induction values. The fields for
sensors that are not connected will show –82,000 nT.
X: -12345/-21nT
Y: 54321/5nT
Z: 12332/43nT
If all three sensors are connected, placing the processor module in Calibration Mode by pressing F2 will
result in a display similar to below. The actual values are not important and will depend on the local
environment and orientation of the sensors. For testing purposes, it is only necessary that the sensors
display a value other than –82,000 nT/0 Hz. If one or two sensors are connected, only those fields will
show magnetic induction and frequency. The fields for sensors that are not connected will show –82,000
nT/0 Hz. Press F2 to exit Calibration mode.
X: 24324nT/46847Hz
Y: 8013nT/55531Hz
Z: 10013nT/45745Hz
If a frequency counter is connected to the output of each sensor, the counter should show a frequency
close to the frequency on the SAM-III display when the processor module is in Calibration mode (the
tolerance is not specified). Note: The sensor output is a logic level squarewave, and it is possible the
frequency counter will measure an odd harmonic. A lowpass filter can be used to reduce harmonic
levels.
The sensors have a normal operating range of approximately ±50,000 nT, which corresponds to a
frequency range of approximately 125 kHz at –50,000 nT to 50 kHz at +50,000 nT. A magnetic induction
of 0 nT corresponds to the frequency of about 70 kHz. These above values are given for reference and
troubleshooting. They are not guaranteed in any way and users should expect variations.
It has been our experience that, if a magnetic induction value and frequency are shown in the
appropriate sensor field of the display when the SAM-III is in Calibration mode, the sensors are
connected and working properly. No additional testing or validation is required.