How can I adjust the sampling time when taking air velocity measurements?
In the Q-TRAK Plus, each sensed parameter is measured internally at least once per second and is referred to as an instantaneous value. A single instantaneous value is not the best representation of an accurate IAQ parameter measurement. Rather, an average of several instantaneous values over a period of time (called a “time constant”) provides a more accurate measurement. This average is updated once per second and is therefore a moving average calculation. The Q-TRAK Plus is shipped new from the factory with a default “time constant” setting of one minute. The time constant is the window of time over which the instantaneous values are averaged. For example, with a time constant setting of 10 seconds, the current measurement is the average of all instantaneous values over the previous 10 seconds. The time constant setting is user-selectable between 2, 5, 10, 15 and 30 seconds and 1 minute. This allows the user to adjust the time dampening effect on the real-time display in the survey
