E-5D: How to check if Internal Sensors are calibrated correctly
The internal temperature/humidity sensors in an E-5D may display different readings than the external sensors connected to the system. Typically, internal sensors display higher temperature readings and lower humidity readings, as they are inside a metal case with little airflow. An increase in temperature without any change in the amount of water held in the air can cause relative humidity to decrease.
To see if the internal sensor is calibrated correctly, compare the dew point of the air being read by the internal sensor to the dew point of the air being read by the external sensor. Unlike humidity, dew point is not affected by a temperature increase. If the calculated dew point is the same for both sensors, the sensors are reading the same air and are calibrated correctly. If the calculated dew point is not approximately the same for both sensors when they are placed next to each other, contact technical support at 1-800-742-8324 (US & Canada) or 1-330-562-7070 (International).
To calculate dew point, you will need both temperature and relative humidity. Use an online dew point calculator to determine approximate dew point measurements. For external sensors, the E-STHSM-Ex and E-STHSB Temperature/Humidity/Dew Point Sensor can be used for continuous dew point monitoring.