9 Calibration
Each channel of the1529 is calibrated independently of the other channels and
has itsown set of calibration parameters. The 1529 should be calibrated at reg-
ular intervalsto ensure that it continues to measure with proper accuracy. Cali-
brationshould only be done by qualified, authorized personnel. When the 1529
is recalibrated, all four channels are calibrated each calibration cycle.The cali-
bration label indicates the calibration date and recalibration due date for the en-
tire instrument.

9.1 PRT and Thermistor Calibration

The followinginformation is for PRT and thermistor channel calibrations. The
adjustable parameters are listed in the following table.
Parameter Description
C0 PRToffset parameter
C100 PRTscale parameter
C400 PRTlinearity parameter
C0K Thermistoroffset parameter
C10K Thermistorscale parameter
C100K Ther mistor linearity parameter
DATE Recordsthedate the PRT or Thermistor channel
wasca librated
DUE Record the date the PRT or Thermistor channel cali-
brationexpires

9.1.1 PRT Calibration Parameters

Three adjustableparameters are used for calibration: C0, C100, and C400. The
C0 parameter directly affects the measurement at 0Ω. It has negligible effectat
100Ωbutsignificant affect at higher resistances. The C100 parameter directly
affectsthe measurement at 100Ω. It has negligible effect at 0Ωand proportion-
ately greater effectthe higher the resistance. The C400 parameter directly af-
fects the measurement at400. It has negligibleeffect at 0Ωand 100Ωwith
greater effectas the resistance increases. Each of the p arameters has positiveef-
fect at their primary resistances: increasing the valueo f the parameter increases
the measured resistance. The theoretically normal valuefor each is 0.
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9 Calibration
PRT and Thermistor Calibration
Table 1 3 PRT and Thermistor Calibration Parameter Description