Intelligent sensing

SGX Sensortech

AN intelligent air quality sensing module from SGX Sensortech is intended to remove the hassle from monitoring air quality in the car, the home, the workplace or the environment.
A significant contributor to poor air quality is a group of low boiling-point gases known as volatile organic compounds (VOCs). These gases occur naturally, are produced by human metabolism and industrial or combustion processes.
There is growing evidence that VOCs contribute to the incidence of respiratory disease and associated healthcare costs. In the workplace, it is believed they impact absenteeism and productivity as a result of what is known as sick building syndrome. Even if harmless to humans, many VOCs are highly odorous and contribute to unpleasant smells.
The new VZ-87 air quality module from SGX Sensortech makes the process of detecting VOCs simple, says the company. Using innovative metal oxide semiconductor
chemistry supported by a micro-electromechanical structure (MEMS), the core sensing technology provides a swift response to changes in the levels of a wide range of VOCs and hence air quality. The technology, which has been produced in high volumes and to rigorous quality control by SGX for more than 10 years, is already well established in the automotive sphere where it is linked with car HVAC systems to control air intakes. The low power module incorporates an advanced signal processing algorithm to produce a range of outputs including analogue, digital and pulse-width modulated.
In addition, the proprietary algorithm automatically compensates for small changes in sensor output over time and provides calibration-free operation. Not only does the sensor produce an effective means of monitoring the level of VOCs in the air, it also provides an equivalency signal for the concentration of carbon dioxide present; CO2 is commonly used as a proxy for air quality.

Where it can be used
The sensing module is said to be ideal for applications like occupancy detection, to reduce energy costs by the intelligent control of heating, ventilation and air conditioning systems. Other applications include vehicle cabin air quality; bathroom and kitchen fan control; and air cleaners and purifiers.
The VZ-87 is just the first in a new series of air quality modules; future versions will be customised to specific applications or customer specification, signal processing requirements and volume demands and will include other air quality parameters such as temperature and humidity.