VPeN (vapour phase e-nose) is a real time water quality meter, for speditive water quality monitoring and control. In particular main idea is based on the possibility to use cheap gas sensors inserted into confined expansion chamber to detects the presence of volatile pollutants in the vapour/gas-phase (atmosphere) overlooking the aqueous-phase.
VPeN was developedstarting from the cooperation between myHermes Srl and the research laboratory AeFLAb of the Politecnico di Bari.
The VPeN system is based on a microprocessor for collect and pre-processing signals from the transducers and peristaltic pumps, to determine the pump and blower cycles and to control the water heater according the measurements parameters.
The same microprocessor (Linux based O.S.) handles communication with the HUB well as the key tasks such as local data storage, diagnosis and regular technical inspection and maintenance call.
The device integrates up to 8 gas sensors. These sensors show a certain degree of affinity towards a specific gas but are sensitive towards a wide spectrum of gas types with overlapping sensitivities. These sensors have been mounted in a stainless steel sensor chamber. Additionally air pressure, temperature and humidity sensor has been installed in the sensor chamber the compensate the sensors relative errors. Fresh air is used as cleaner gas and measures start when the sensor resistances in the presence of the cleaner gas are stabilized (zeros time). Before a new measurement, the value of the initial voltage output (Vo) is acquired and used as the mean value of the measurements