MTS Clip-On Gages - Manual (Page 22)

Calibration 22
adjustment procedures in this manual use 80% full scale as the reference
value.
Delta K
Delta K is a feature of DC conditioners manufactured by MTS Systems
Corporation. Delta K compensates for differences in symmetry between
the positive and negative outputs of the transducer. Gain is usually
adjusted to calibrate the compression half of the transducer range. Use
Delta K to calibrate the tension half of the transducer range.
Symmetrical versus Asymmetrical Clip-On Gages
Some clip-on gages can have only positive output (tension only), some
transducers can have both positive and negative output (tension and
compression). It is also possible that the clip-on gage has asymmetrical
travel (such as +3 mm and -1 mm). It is important that you determine
the full scale travel range of the clip-on gage before proceeding.
For example
Suppose you have a transducer with an asymmetrical travel of +3 mm
and -1 mm. It is desired to adjust the conditioner to have a full-scale
output equal to the full travel range of the clip-on gage. In this case +3
mm would approximately equal +10 V, and -1 mm would have an
output of -3.3 volts. Gain would be adjusted so that -0.6 mm would
yield -2 volts, and delta k would be adjusted so that +2.4 mm would
yield +8 volts while adjustments to zero are made to keep the null
position of the clip-on gage at zero.
In all cases, the actual displacement should be used to determine the
calculated output.
Note It might be difficult to obtain a displacement value of exactly
80% full scale. In those cases, find a displacement that you can
achieve and calculate new conditioner output value for the
displacement. For example, suppose the calibration block is set
for 7.94 mm. Then your desired output would be 7.94 V.
Actual Displacement
Full-Scale Range
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⎝ ⎠
⎛ ⎞ 10 V
× Calculated Output =