Measurement Computing CIO-DAC04/12 - Manual (Page 13)

5. CALIBRATION AND TEST
Every board was fully tested and calibrated before leaving the factory. For normal environments, a calibration interval of 6 months to
one year is recommended. If frequent variations in temperature or humidity are common, recalibrate at least once every three months.
It requires less than 10 minutes to calibrate the CIO-DAC04/12-HS.
5.1 REQUIRED EQUIPMENT
You will need a 4½ digit digital voltmeter and a few pieces of wire.
You do not need an extender card to calibrate the board but you will need to have the cover off your computer with the power on, so
trim pots can be adjusted during calibration. A plastic screwdriver is supplied with your board. In the event that the screwdriver is
dropped into the PC, no damage will result from short circuits.
5.2 CALIBRATING THE D/A CONVERTERS
The D/A's are calibrated by writing a code to the D/A, measuring the analog output voltage and then adjusting potentiometers so that
the output voltage is correct. The entire procedure is described in the InstaCal, calibration routine.
Calibrate each channel for the range you intend to use. When the range is changed, a there may be a slight variation in zero and full
scale gain.
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