Kaman digiVIT - Manual (Page 15)

www.kamansensors.com PART NO: 860525-001
Last Revised 9/16/2013
- 15 -
PART 6 - CALIBRATION EXAMPLES
6.1 General Information
There are some rules of thumb when using the digiVIT:
1) The standard range is 1/3 the diameter of the sensor against a non-ferrous target, such
as aluminum.
2) The offset (closest point to sensor face) should be set at 10% of the standard sensor
range.
3) The range against non-magnetic targets can typically be extended to 150% of the
standard range with reduced linearity and thermal sensitivity.
4) Magnetic targets will have a range about 20% of the diameter of the sensor but
performance can vary significantly depending on the material and it's processing.
5) Larger sensor diameters (>35mm) are not as affected by the target material as smaller
diameter sensors and will typically work better with the magnetic targets.
6) When using magnetic targets that are moving laterally to the sensor face (i.e. rotating
targets) the temperature compensation option should not be used (regardless of sensor
diameter). This is due to a 'generator effect' caused by fluctuations in permeability over
the surface of the target influencing the temperature measurement of the sensor.
7) For most ranges, the 6 point calibration will typically yield good to very good results while
the 21 point calibration will give excellent results.
8) When the calibrated range is less than 10% of the standard range a 2 point calibration
will usually yield good results. At ranges less than 5% of the standard range, a 2 point
calibration is recommended.
9) All calibrations can be performed through the front panel or via a UDP command over
the Ethernet interface.
10) For all calibrations, the front panel interface assumes a certain calibration order in the
data points. For calibrations via the UDP interface, data can be taken in any order with
the 'Done command' (C2, C6, CD, or CAM depending on the calibration type) issued
when the calibration is complete.
11) Calibrations can be performed from MIN to MAX range or MAX to MIN range provided
the calibration steps precede sequentially.
Calibration records for 2 point, 6 point, and 21 point calibrations can be downloaded from the
Kaman website:
www.kamansensors.com .