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2015/01/12

0925 G1: 2mbar, P1: 17ubar, G2: 0mbar. External pressure sensor attached to He3 pump exhaust lines reads 4.0mbar.
0948 Fill LN2 cold trap full.
1005 Fill He gas through vent valve, V7, V11a, V12a till G1 reads 935mbar. P1: 16ubar. Open V1.
1022 G1: 839mbar, P1: 32ubar.
1032 G1: 849mbar, P1: 90ubar. Close LN2 cold trap 1 speedivalve because of rising G1 pressure.
1037 G1: 847mbar, P1: 150ubar.
1041 G1: 844mbar, P1: 190ubar. Add more He gas until G1 reads 999mbar. Open V1.
1051 G1: 876mbar, P1: 300ubar.
1056 G1: 871mbar, P1: 380ubar. Open V6.
1108 G1: 860mbar, P1: 500ubar.
1118 G1: 851mbar, P1: 400ubar.
1126 G1: 844mbar, P1: 380ubar. Open V2, V3 to aid in pumping out fridge lines.
1145 Isolate all valves on IGH. Open V7, V12a, cold trap 1 speedivalve, V13a, V3. G1: 732mbar.
1155 Test fails, pump out. G1: 608mbar, drops to a steady 47mbar. Does not rise, indicating no flow.
1320 G1: 637mbar drops and stabilizes at 45mbar indicating no flow. Pump out He gas.
1520 Add gas for “non-traditional” throughput test. G1: 561mbar, P1: 65ubar. Open V1, G1 drops to 43mbar.
1535 G1: 42mbar, P1: 75ubar.
1607 G1: 41mbar, P1: 90ubar. Pump out. Kill turbopump (only connection between pump and fridge lines passes through cold LN2 cold trap, which hopefully helps). Commence pumping out with rough pump.
1745 G1: 2mbar, P1: 60ubar. Add He gas to G1 through vent valve and LN2 cold trap 1 until G1 reaches 999mbar. Time to see if there's a new blockage in the fridge or if the behavior's the same. Open V1.
1802 G1: 910mbar, P1: 90ubar. Open V6 to see if pumping out through fridge is possible.
1814 G1: 900mbar, P1: 65ubar.
1820 G1: 894mbar, P1: 50ubar. Open V2 and V3 to aid in pumping.
1847 G1: 1.7mbar, P1: .40mbar. Isolate fridge lines. Lower dewar.