What is the difference between temperature deviation & temperature fluctuation of constant temperature and humidity chamber?

The constant temperature and humidity chamber belongs to the environmental test equipment, the temperature fluctuation and temperature deviation are clearly specified in the relevant national standards of environmental test equipment.

Temperature deviation:
For the same temperature measurement point,The deviation value between measured value (PV value) and standard value (value measured by national certified calibration laboratory); this value is affected by the sensor accuracy and instrument performance, common temperature deviation is between 0.5 degrees C to 1.2 degrees C, the smaller,the better.

Temperature fluctuation:
At the same temperature measurement point, the measured value (PV value) shows the fluctuation state around the target value (SV/SP value); the temperature fluctuation of environmental test chamber is less than 0.5 degrees Celsius,this value mainly reflects the comprehensive performance of temperature detection, system control and heating load.

In conclusion, we can know the difference between the temperature fluctuation and the temperature deviation. If you need to roughly summarize, then the temperature fluctuation is the embodiment of the overall control performance index of the equipment, and the temperature deviation is mainly the performance index of the temperature sensor and the controller.