Smis Instrumentation We are Temperature Humidity Transmitter Suppliers & Manufacturers Suppliers.
What is a Humidity?
A humidity sensor (or hygrometer) senses, measures and reports the relative humidity in the air. It therefore measures both moisture and air temperature. Relative humidity is the ratio of actual moisture in the air to the highest amount of moisture that can be held at that air temperature. The warmer the air temperature is, the more moisture it can hold. Humidity / dew sensors use capacitive measurement, which relies on electrical capacitance. Electrical capacity is the ability of two nearby electrical conductors to create an electrical field between them. The sensor is composed of two metal plates and contains a non-conductive polymer film between them. This film collects moisture from the air, which causes the voltage between the two plates to change. These voltage changes are converted into digital readings showing the level of moisture in the air.
Types of Humidity / Dew Sensors
There are many different kinds of humidity / dew sensors and at Smis Instrumentation we stock many of the most common types categorized by accuracy, operating temperature range, humidity range, supply voltage, packaging type and supply current. The parametric filters on our website can help refine your search results depending on the required specifications.
The most common sizes for supply voltage are 3 to 5.5 V and 4.75 to 5.25 V. We also carry humidity / dew sensors with supply voltage as high as 15 V. Supply current can be between 100 µA and 15 mA, with the most common humidity / dew sensor chips using a supply current of 100 µA, 500 µA and 2.8 to 4 mA.
You can get a relative humidity transmitter in a variety of styles and formats. A relative humidity transmitter can come in wall-mount, duct-mount and with a remote probe. The wall mount transmitters feature either an internal sensor or an integral sensor to measure temperature and humidity measurements. Duct-mount transmitters feature an extended probe that is inserted into an HVAC system or small places. These transmitters are mounted externally, while the sensor is within the area being measured. A remote relative humidity transmitter features a remote probe can be used in applications where the transmitter is mounted in one spot while the probe is taking measurements in a different part of the room. Davis Instruments features transmitters for constant humidity, temperature, and dew point monitoring that range from basic-use to intrinsically safe from trusted brands like Valsala, GE Sensing and Testo. If you have questions about purchasing a relative humidity transmitter contact a Davis Application Specialist today.