Gas and safety control systems for drift and He chambers in FINUDA

In modern high energy and nuclear physics experiments, the complexity of gas detectors and their operation in areas not accessible during the data taking periods require dedicated gas and safety systems running automatically and controlled by PC. In the FINUDA experiment, to control the gas systems of the drift and He chambers and to monitor the relevant parameters, as helium atmosphere purity and gas mixture composition, affecting the experimental performances, three programs were written in National Instruments (NI) Lab VIEW and datalogging and supervisory control environment. Two safety systems work continuously to check the hydrocarbon leakages, inside and outside the He chamber: pre-alarm and alarm signals feed a NI field point, where a real time program sends, via Ethernet, the FINUDA safety status to all detectors