Kaman DIT-5200L - Manual (Page 8)

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Kaman Precision Products PART NO: 860522-001
www.kamansensors.com Last Revised 11/16/2012
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3.4 Optimizing Performance
There are several things to be aware of when using the DIT-5200L in order to optimize the
performance of the system.
 Insure that there are no ‘incidental targets’ – i.e. targets that the sensor may see that are
not to be measured.
 Insure that the sensor is not tilted with respect to the target as this will cause additional
non-linearity.
 Make sure that the system is set up with the proper null gap – electrical nulling of the
second sensor in a pair is best.
 Insure you are using the specified calibration material (aluminum is the standard).
 Make certain that you are using stable fixturing and mounting of the sensors.
 Ensure the target is 3 sensor diameters in size and is thick enough to prevent penetration
of the magnetic field. (reference section 3.6 on Targets)
 The system will perform the best if both sensors are in a similar thermal environment –
avoid temperature differentials between the sensor pairs.
3.5 Factors That May Degrade Performance
Unequal Loading
This refers to an unequal amount of conductive material within the field of one sensor as opposed
to the other sensor in the pair (the sensor’s field is approximately three times its diameter).
Unequal loading causes asymmetrical output from the sensors which induces non-linearity in the
system output. Ideally, no conductive material other than the target should be in the sensor’s
field. Some loading may be acceptable if it is equal and the sensors are calibrated in place. Even
then, sensor loading may cause non-linearity. If unable to calibrate, then loading is too great.
Unequal Displacement
For targets using pivot point mount, the system should “see” equal displacement: i.e., the pivot
point of the target is perfectly centered between the sensors. If the pivot point is a fraction of a
centimeter off, it can introduce non-linearity into the system.
 The pivot point must be on a common line between the centerline of a pair of sensors.
 The axis of tilt must be a perpendicular bisector of a line between the centerlines of a sensor
pair.
 The pivot point must be positioned on the target so as not to introduce a translation error.
This error, a function of angle, is caused by slight changes in the effective null gap as the
target moves about the pivot. This results in non-linearity.
 The pivot point must not move or change with time.