1. Provisional Hydrogen System Control Sequence TW Bradshaw Y Ivanyushenkov D Baynham MJD Courthold

2. Control logic – Fill Sequence Chiller on Set TS1_sp = TS1_initial PV2,3,5,7,14,17,18,19 closed CV4 closed PV1 open VP2 on, PV20 open Cooling System on Set TS2_sp = 15K Start Pressure Control Loop Start Vac Monitor Open PV2,3 Open CV4 TS1<TS1_sp And VG3<1mbar PG1  PG1_sp Close PV2&3 and CV4 Stop Pressure Control Loop Set TS1_sp = TS1_low Open PV5 LS1 > LS1_sp H2 System Ready Increment/Decrement TS1 Empty Sequence VG3<1mbar Vac monitor Pressure Control Yes No Yes No Yes No

3. Empty Sequence Open PV7 Close PV2,3,4 Set TS1_sp = TS1_low Set TS2_sp = 20K Stop cryocooler Start Absorber Heater Control Loop LS1<LS1_low Empty Sequence Yes No Close PV1 PG2<0.1bar AND TS3>100K H2 System Empty Yes No 1bar<PG2<1.3bar Increment/Decrement TS3 Absorber Heater Control Yes No Stop Absorber Heater Control Loop TS3>30K Yes No

4. Helium Purge Sequence VP1 On Close PV1,14,17,18,19 Open PV2,3,5,7 Open CV4 100% Close PV19 Open PV18 Open CV4 5% to control flow VG5<1mbar H2 System Purged Purge Sequence No Open PV19 Yes 1bar<PG1<1.3bar AND 1bar<PG2<1.3bar Close PV19 Open PV18 Open CV4 5% to control flow VG5<1mbar No Close PV18, Open PV19, Open CV4 100% Yes 1bar<PG1<1.3bar AND 1bar<PG2<1.3bar Close PV19 Open PV18 Open CV4 5% to control flow VG5<1mbar No Close PV18, Open PV19, Open CV4 100% Yes 1bar<PG1<1.1bar AND 1bar<PG2<1.1bar Yes No Close PV18