Chapter 9 – Maintenance
TestEquity 101H Temperature/Humidity Chamber
Page 77
How to Verify the Temperature Calibration
!
CAUTION:
TestEquity does not recommend performing the controller calibration
procedures unless you have verified that the controller is actually out of
calibration.
TestEquity recommends verifying the calibration before attempting to actually perform a
calibration. The microprocessor-based instrumentation used in TestEquity chambers seldom goes
out of calibration. If you try to calibrate the instrumentation before determining that calibration is
necessary, you may make it worse if done incorrectly.
Variations in temperature throughout the chamber interior are NOT a measurement of controller
accuracy. These variations, called “gradients”, are a function of the physical design of the
chamber and its airflow, the characteristics of the test sample, and how it is oriented in the
chamber. You cannot “calibrate” to improve gradients. The correct way to adjust what the
temperature controller “displays” compared to what is measured at some point other than the
controller’s sensor, is with the “Calibration Offset” parameter.
The easiest way to verify the instrumentation accuracy is with an independent calibrated
temperature sensor and display. Place the sensor near the chamber’s sensors, which are located
near the conditioner fan grille. If the readings agree within the specified limits above, then no
calibration adjustments are necessary.
If adjustment of the F4T Temperature Controller is necessary, refer to the section for “F4T
Controller Calibration”.
