Kaman KD-2300 - Manual (Page 33)

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Part IV: Calibration KD-2300 Instruction Manual
6. Repeat Steps 3 through 5 as many times as necessary until you reach the
desired output voltage at each point. No further adjustment of the
Zero, Gain and Linearity controls will be needed when proper
calibration is attained.
Alternate Bipolar Output Calibration
You may not be able to achieve maximum sensitivity using this
technique. This method may be preferred if the maximum voltage does
not exceed the op-amp saturation voltage (5.5 V for 8 volt internal
regulation.)
1. Use the Full-Scale procedure in this section to calibrate the system
initially from 0 Vdc to the desired maximum.
2. Position the target at mid-scale and adjust the Zero control
counterclockwise until output reads 0 Vdc.
3. Check the two ends, the points closest and farthest from the sensor, to
see that they equal minus and plus one half of the original full-scale
output voltage. For example, if your original full-scale voltage was 0-4
Vdc, it should now be -2 to +2.
In theory, adjusting the Zero control in this technique should not affect
sensitivity or linearity. In practice, however, you may see a very slight
change indicated by voltage readings other than minus and plus one-half
full scale. You may then choose to use the primary bipolar technique to
fine-tune the calibration.