ICARUS Internal Cryogenic Sensors Purpose This system provides a means of reading the temperature and liquid level sensors internal to the ICARUS cryostats. Resistance Temperature Detector (RTD) 30 locations per T300 cryostat Type Pt1000 in cryostat 1 Platinum RTD with R=1000Ω at 0°C Type Pt10k in cryostat 2 Platinum RTD with R=10kΩ at 0°C Provide interlock during initial LAr fill (Tmax−Tmin<50°C) Monitor LAr temperature during normal operation Resistive Level Meters (RLM) 4 locations per T300 cryostat (five 470Ω resistors per RLM) Resistance lowers ~25% when immersed in LAr Alert when nearing top during initial LAr fill Monitor LAr level during normal operation RTD Installation RLM Installation

ICARUS Internal Cryogenic Sensors Readout Controlled by a PLC, Beckhoff CX5120-0115 performance CPU module, located on the mezzanine Four control panels located on top of the cryostats, near the chimneys for RTDs and RLMs Uses Beckhoff EL3204- 0200, universal RTD modules (resistance range 100Ω to 240kΩ) Electrical isolation between panels for grounding DC excitation current to sensors (low noise) Connected to main cryogenic controls PLCs Data accessible through iFIX HMI and saved in historian (same as all other cryo data) OPC server makes data available over Fermilab network (i.e. can be read by EPICS) System Layout Control Panel

ICARUS Internal Cryogenic Sensors Feedthrough Flanges Using four feedthrough flanges from original installation, plus three new feedthrough flanges All feedthrough flanges installed Wiring Verification Some wiring errors found (broken or shorted wires) Wiring errors inside cryostats cannot be repaired; bad channels noted on drawing 5 RTDs in NE corner lost due to lost connector inside cryostat 1 shorted resistor on NE RLM 1 bad RTD (broken wire?) in SE corner 1 bad RTD (broken wire?) in SW corner Readout Boxes Assembled and completed safety review To be installed inside racks housing TPC power supplies Save space on top of cryostat Test conducted to ensure noise will not affect TPC power supplies Connector to Cold Side of Feedthrough Flange

ICARUS Internal Cryogenic Sensors Next Steps Install readout boxes in the top of corner racks on top of warm vessel First box expected to be installed today Expect other three in next week Route wires from boxes to flanges Part of overall cryogenic system wiring Expected over next couple weeks PLC Programming and verification of sensor reading Part of overall cryogenic system programming and commissioning Expected over next three weeks