Humidity Sensor with the H14DL
The humidity sensor described is designed to provide accurate humidity readings while incorporating temperature compensation to enhance measurement precision. The sensor operates optimally when AC voltage is applied, as DC voltage can lead to irreversible damage. Therefore, it is crucial to ensure that the circuit is configured to supply AC voltage only, avoiding any direct current conditions.
Environmental conditions must be controlled to maintain sensor accuracy and longevity. Factors such as condensation, freezing temperatures, dust, mist, oil, and alcohol can adversely affect sensor performance. Proper housing or environmental shielding may be necessary to prevent exposure to these elements.
In the circuit setup, the H14DL component should be replaced with two minimum resistors: one with a value of 22 kΩ and another with a value of 51 kΩ. This modification is essential to calibrate the sensor properly. Adjusting the variable resistor (RV1) is a critical step in the setup process. By tuning RV1, the output voltage between the sensor's output and ground should be calibrated to read 1.40V on a voltmeter. This voltage level serves as a baseline for subsequent humidity measurements.
The sensor's output will correlate with humidity levels according to a predefined table, which specifies the output voltage for various humidity percentages. The accuracy of these readings is approximately ±5%, indicating that while the sensor provides reliable data, some variability may occur. Regular calibration and adherence to environmental guidelines will enhance the performance and reliability of the humidity sensor in practical applications.A humidity sensor with temperature compensation built-in. Never apply a DC voltage to the sensor, even measuring the sensor with an ohmmeter will damage the device, always ensure that an AC voltage is applied. Avoid condensation, freezing, dust, mist, oil, alcohol, etc. To set up this circuit replace the H14DL with Min Res 22Kohm and Min Res 51Kohm as shown, Acjust RV1 until a voltmeter between output and ground reads 1.40V.
The output will then be as shown in the table to an accuracy of about ~5%. 🔗 External reference
Related Circuits
Light Sensitive Switch is a simple project which operates a relay when the light falling on the LDR goes below a set point. More: Input - 12 V @ 55 mA Relay output - NC-C-NO Onboard preset to set the level Power-On...
This is a low-current temperature sensor with a single-wire output. The number of pins required to interface with a microprocessor is minimized by this design. The low-current temperature sensor operates efficiently by utilizing a single-wire communication protocol, which significantly reduces...
This device is a highly effective capacitive sensor. In North America, it is primarily utilized for detecting wooden beams behind drywall or plaster. This model is preferred over newer designs due to its reliability, as it does not frequently...
Many individuals install motion detectors in their backyards or homes to automatically turn on lights when movement is detected. Motion sensor lights have gained popularity and are increasingly utilized in various settings. Businesses frequently employ them in bathrooms, where...
This circuit responds to the presence of any conductive object, including humans. It does not detect object movement but can function as a proximity sensor. The circuit operates on the principle of capacitive sensing, utilizing a capacitor to detect changes...
It's basically a photovore with a couple tactile sensors. It's rather complex but can give neat behaviors with modifications to the circuit. At this point I don't have any plans to give more information on this circuit so your...
