<< Click to Display Table of Contents >> Navigation:  Hardware Overview > Sensors and Probes > HCD-IC > Humidity and Temperature Calibration/Adjustment > Basic Recommendations > Temperature Calibration in Air

Despite its apparent simplicity, calibration in air can be tricky, primarily because of temperature gradients. In order to be able to correctly calibrate and adjust the temperature measurements provided by a probe, you must be able to meet the following requirements:

 

oBoth the probe and the reference thermometer should be ventilated by the same stream of air. Any dust filter used to protect the sensors should be carefully removed from the probe. If the probe has a protective slotted cap (no filter element), this may be left on the probe.

oAir velocity at the sensor should be within the limits of 200 to 500 feet/minute (1 to 2.5 meters/second). Any comparison between two instruments at a velocity under 200 feet/minute may not be valid. Air velocity above 500 feet/minute may damage the unprotected humidity sensor.

oThe temperature of the air stream should be practically constant.