11 Calibration Procedure
11 Calibration Procedure
11.1Calibration Procedure
Calibration of this instrument should be performed at regularly scheduled inter- vals by qualified authorized personnel in accordance with your company’s pol- icy. Following is the recommended procedure for calibrating this instrument.
11.1.1Calibration Equipment
Calibration requires a standard thermometer that is adequately accurate and fits properly into one of the reference holes in the block. Recommended equipment includes a laboratory grade PRT with a length of 30 to 300 mm (9 to 12 inches) and a diameter of 4.76 or 6.35 mm (3/16 or 1/4 inches). The combined accu- racy of the PRT and the readout which used to display the temperature should be 0.025°C or better.
11.1.2Calibration
The accuracy of the instrument over the full range is determined by the values of the calibration parameters R0, ALPHA, DELTA, and BETA. The calibration procedure involves measuring the error between the instrument and the refer- ence thermometer at several temperature throughout the range and adjusting the calibration parameters as necessary to reduce the errors to within acceptable limits. The stated accuracy of the instrument can be found in the specification table in Section 3.1. Because of the way the calibration parameters affect the temperature the simplest way to proceed is to measure the errors at 0°C, 100°C, 50°C, and
•Set the
•Set the
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