LN2 filling system 1.Filling the buffer tank 2.Filling the collector tube 3.Filling the detectors 4.Venting the collector tube 5.Monitoring then go to 1 or 2

1. Filling the buffer tank Automatic? Alarm on the buffer tank to alert operators?

2. Filling the collector tube Logic sequence: – Open VP – Open VIN – While FP wait for TP to get to LN2 value – Close VP

3. Filling the detectors Logic sequence: – (VIN already open, VP closed) – Open VDi – Wait until TVi is at LN2 temp – Close VDi

4. Venting the collector tube Logic sequence: – Close VIN – Open VP

5. Monitoring Logic sequence: – Check P,V against alarm threshold ->Step 1: Fill the buffer – Check Tdi against limit value ->Step 2: Fill all the detectors – Check time since last fill ->Step 2: Fill all the detectors

Implementation – collector VIN 24V NI 9476 VP 24V NI 9476 NI 9217NI – 40 V DC NI 9217 Collector Safety Valve(s) NI /column NI /column NI V AC1 +1/column VDC1/column

Implementation - detector VDi 24V NI 9476 NI 9217 Collector Safety Valve(s) NI 94761/detector NI V AC1 /detector Dewar TDi

Implementation – monitoring V Collector P NI 9217 NI 9425? NI 9217 NI 9425? Dewar Crystal NI 9217

Custom modules To NI 9217 PTi From NI V Power On/Off Open / Close Opened / Closed Powered Y/N To NI 9425 Read PT100 Distribute valve signal Command one valve V DC Read flux sensors M1 M2 M3 M4 12V

M3 working principle 12 V Power On/Off Open / Close Opened / Closed Powered Y/N M3 12V NI 9476 Valve 12 V

Connection diagram Compact Rio Crate (6 x NI 9217, 1 x NI 9476, 1 x NI 9425) PT100 Prox M1 12V Prox M2 M3 Valve 12V? M4