Calibration, 1. pitfalls, 1a. dimensional standard – Kaman KD-5100 User Manual
Page 20: 1b. recalibration, 1c. thermal equilibrium
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until the system output reads 0Vdc (ideally, 0.000 volts). This output means the sensor is
positioned correctly.
11-5. Repeat steps 11-3 and 11-4 for sensor S4 and S2.
11-6. The system is now ready to use.
12. CALIBRATION
12-a. These systems are shipped from the factory pre-calibrated for a user specified
measuring range, sensitivity, and target material. They do not normally require
calibration or re-calibration. Yet some applications dictate the availability of this option.
12-b. The calibration procedure is very simple. The problems arise in finding an
accurate enough dimensional standard and a stable environment.
Therefore, there are some pitfalls…
12-1. Pitfalls:
12-1a. Dimensional Standard:
To calibrate, you need some dimensional standard (a micrometer, laser interferometer, a
weight to provide a known deflection, etc.). This should be a standard that you believe in
and know to be accurate and repeatable. Whether you are measuring in mils, microns,
micro-radians, or whatever, you must have a means of accurately positioning the target,
using the dimensional standard, to the desired measurement units.
Kaman Instrumentation uses a laser interferometer as a primary dimensional standard for
calibration.
12-1b. Recalibration
Recalibration to a sensitivity and/or measuring range significantly different from the
factory calibration may not be possible. For example, if you purchased a standard system
calibrated 0 to 9 volts over a 9 mil measuring range (1V/mil) and attempted to recalibrate
for 9 volts over a 3 mil measuring range (3V/mil) there may not be sufficient gain
adjustment to do this. These units are built with component values selected for each
application. Therefore, changes in measuring range, sensitivity, or target material may
not be possible and will require reconfiguration by Kaman Instrumentation.
12-1c. Thermal Equilibrium
The mounting/cover plate helps maintain thermal equilibrium inside the module and acts
as a heat sink for the hybrid circuit. The hybrid has two watts of power to it and needs