Novel Control System for the LHCb Scintillating Fibre Tracker Detector Infrastructure

During the Long Shutdown 2 of the LHC at CERN, the LHCb detector is upgraded to cope with higher instantaneous luminosities. The largest of the new trackers is based on the scintillating fibres (SciFi) read out by SIlicon PhotoMultipliers (SiPMs). The SiPMs will be cooled down to -40°C to minimize noise. For performance and space reasons, the cooling lines are vacuum insulated. Ionizing radiation requires detaching and displace the readout electronics from Pirani gauges to a lower radiation area. To avoid condensation inside the SiPM boxes, the atmosphere inside must have a dew point of at most -45°C. The low dew point will be achieved by flushing a dry gas through the box. 576 flowmeters devices will be installed to monitor the gas flow continuously. A Condensation Prevention System (CPS) has been introduced as condensation was observed. The CPS powers heating wires installed around the SiPM boxes and the vacuum bellows isolating the cooling lines. The CPS also includes 672 temperature sensors to monitor that all parts are warmer than the cavern dew point. The temperature readout systems are based on multiplexing technology at the in the front-end and a PLC in the back-end.