CWS220A

The CWS220A is a wireless version of our SI-111 infrared radiometer. It measures the surface temperature of an object without physical contact. This radiometer has an internal 922 MHz spread-spectrum radio that transmits data to a CWB100A Wireless Base Station or to another wireless sensor. The 922 MHz frequency is used in Australia, Israel, and other countries worldwide.

The CWS220A includes a thermopile, which measures surface temperature, and a thermistor, which measures sensor body temperature. The two temperature sensors are housed in a rugged body that contains a germanium window. It is battery powered using either alkaline batteries or a rechargeable battery and a solar cell.

The CWS220A can route its transmissions through up to three other wireless sensors. A data logger is connected to the CWB100A base station for processing and storing its data. The CWS220A interfaces with a PC for configuration via the A205 CWS Sensor to PC Interface.

The calibration coefficients used for determining the target temperature by means of the Stefan-Boltzman equation are stored in the CWS220A at the time of calibration.

Why Wireless?

There are situations when it is desirable to make measurements in locations where the use of cabled sensors is problematic. Protecting cables by running them through conduit or burying them in trenches is time consuming, labor intensive, and sometimes not possible. Local fire codes may preclude the use of certain types of sensor cabling inside of buildings. In some applications measurements need to be made at distances where long cables decrease the quality of the measurement or are too expensive. There are also times when it is important to increase the number of measurements being made but the data logger does not have enough available channels left for attaching additional sensor cables.