| 1310 | Perform mixture throughput test at MC = 300 K using above procedure with 3He pump on. Let G1 rise to 550 mbar before Step 3, then it falls to 40 mbar and starts to rise. Throughput = 5.9 mbar/min. |
| 1135 | With 1K Pot speedivalve and needle valve closed, pump on Main bath with scroll pump.
Once P2 < 100 mbar, open 1K pot speedivalve and needle valve (5 turns) to pump out 1K pot volume to < 1 mbar on P2. |
| 1145 | Close off scroll pump, then pressurize bath and 1K Pot (both sides) to about 0.5 bar with helium. Then pump it out again with scroll pump to < 1 mbar. |
| 1150 | Close off scroll pump, then pressurize bath and 1K Pot (both sides) to about 0.5 bar with helium. Then pump it out again with scroll pump to < 1 mbar. |
| 1155 | Pressurize main bath and 1K Pot (both sides) with helium to 370 mbar +1atm on G3, then close 1K Pot speedivalve and needle valve. |
| 1200 | Turbo on IVC = 10 nbar. With turbo valved out for two minutes, IVC = 250 nbar. |
| 1200 | Let 5.4 mbar He exchange gas into IVC. |
| 1210 | As on 2020 Oct 6, we will flow mixture through the fridge during LN2 cooldown. Let mixture from dump through cold LN2 Trap 2 to fridge, both sides. Then we'll isolate the sides and circulate with V6 open partially and mix open to dump. V9, V13b, V12b+speedi, V1, Condenser speedi, Still gate valves open, 3He pump on. Now open V6 to 11.8%. (adjusted this later, see below) |
| 1215 | P1 falls to 0.10 mbar. |
| 1215 | Try closing V12b speedivalve. G1 falls as it should, showing we have throughput. Falls at 10.5 mbar/min . Open V12b speedivalve again. |
| 1220 | P1 went as low as 0.085 mbar, lower than usual. So I adjusted V6: closed it completely, then opened it to 11.6%. P1 settles to 0.28 mbar. |
| 1230 | Trouble starting Omni_Logger vi because Fridge Computer no longer recognizes the external link to Linux. Instead sending logged data to c:\K100\K100log. |
| 1235 | MC(Cernox) = 296.6 K, Sorb = >249 K (max), IVC = 5.4 mbar, G2/G1/P1 (circulation) = 665/745/0.40 mbar, Level resistor = 0.968 kΩ |
| 1300 | Begin LN2 transfer. |
| | Setup at top of fridge during LN2 transfer. Hose is supported by hoist hook. Level resistor in 3rd port. Bath recovery outlet is open to air.
 |
| | LN2 Dewar pressure seems kinda low, this may be a slow transfer. It was just filled. Tried tilting the Dewar a couple times, that seemed to help a little. We can try pressurizing it through the vent like we've done before but the N2 cylinder is empty, we'd need to use helium. |
| 1305 | Start pressurizing LN2 Dewar through the vent with helium. LN2 Dewar gauge → 8 PSI.
 |
| 1305 | MC(Cernox) = 296.7 K, Sorb = >249 K (max), IVC = 5.4 mbar, G2/G1/P1 (circulation) = 668/745/0.70 mbar, Level resistor = 0.970 kΩ |
| 1315 | MC(Cernox) = 295.1 K, Sorb = >249 K (max), IVC = 4.6 mbar, G2/G1/P1 (circulation) = 669/745/0.80 mbar, Level resistor = 0.976 kΩ |
| 1330 | MC(Cernox) = 285.0 K, Sorb = >249 K (max), IVC = 4.6 mbar, G2/G1/P1 (circulation) = 670/745/1.00 mbar, Level resistor = 0.988 kΩ |
| 1330 | Close V12b speedivalve for 2 minutes to assess throughput. (Condenser pressure G1 should fall.) G1 falls at 11.9 mbar/min. Open V12b speedivalve again. |
| 1345 | MC(Cernox) = 261.4 K, Sorb = >249 K (max), IVC = 3.4 mbar, G2/G1/P1 (circulation) = 672/745/1.50 mbar, Level resistor = 0.998 kΩ |
| 1400 | MC(Cernox) = 238.7 K, Sorb = >249 K (max), IVC = 3.0 mbar, G2/G1/P1 (circulation) = 672/745/2.20 mbar, Level resistor = 1.016 kΩ |
| 1400 | Close V12b speedivalve for 2 minutes to assess throughput. (Condenser pressure G1 should fall.) G1 falls at 14.8 mbar/min. Open V12b speedivalve again. |
| 1415 | MC(Cernox) = 211.7 K, Sorb = >249 K (max), IVC = 2.5 mbar, G2/G1/P1 (circulation) = 672/744/3.20 mbar, Level resistor = 1.054 kΩ |
| 1430 | MC(Cernox) = 188.1 K, Sorb = >249 K (max), IVC = 2.5 mbar, G2/G1/P1 (circulation) = 672/744/4.00 mbar, Level resistor = 1.087 kΩ |
| 1430 | Close V12b speedivalve for 2 minutes to assess throughput. (Condenser pressure G1 should fall.) G1 falls at 22.0 mbar/min. Open V12b speedivalve again. |
| 1445 | MC(Cernox) = 161.2 K, Sorb = >249 K (max), IVC = 2.2 mbar, G2/G1/P1 (circulation) = 672/743/6.50 mbar, Level resistor = 1.149 kΩ |
| 1505 | MC(Cernox) = 137.5 K, Sorb = 238 K, IVC = 1.9 mbar, G2/G1/P1 (circulation) = 672/743/19.0 mbar, Level resistor = 1.215 kΩ |
| 1505 | Close V12b speedivalve for 2 minutes to assess throughput. (Condenser pressure G1 should fall.) G1 falls at 38.2 mbar/min. Open V12b speedivalve again. |
| 1515 | MC(Cernox) = 126.0 K, Sorb = 202 K, IVC = 1.9 mbar, G2/G1/P1 (circulation) = 671/742/34.0 mbar, Level resistor = 1.243 kΩ |
| 1530 | MC(Cernox) = 117.9 K, Sorb = 178 K, IVC = 1.9 mbar, G2/G1/P1 (circulation) = 671/741/65.0 mbar, Level resistor = 1.259 kΩ |
| 1530 | Close V12b speedivalve for 2 minutes to assess throughput. (Condenser pressure G1 should fall.) G1 falls at 48.6 mbar/min. Open V12b speedivalve again. |
| | It seems like the transfer is nearly finished. Level resistor is not as high as usual, but we are using a different multimeter, maybe that's why. |
| 1545 | MC(Cernox) = 109.6 K, Sorb = 158 K, IVC = 1.6 mbar, G2/G1/P1 (circulation) = 670/741/400.0 mbar, Level resistor = 1.275 kΩ |
| 1545 | Stop LN2 transfer. Pull out Level Resistor and put ping-pong ball on MB exhaust port. |
| 1555 | Matt exits lab |
| 1645 | MC(Cernox) = 89.7 K, Sorb = 137.4 K, G2/G1/P1 (circulation) = 670/740/max mbar |
| | Setup after end of LN2 transfer.
 |
| 1645 | Matt Fritts body temperature 96.9 °F |
| 1650 | Close V6 and stop circulation pump. |