Notation
- HMI means QT (Quantum Technology) Interface.
System Status
- Confirm via the "Purifier LN2 Overview" HMI page that
- Level is below 75%,
- PTA is below 3 psi, and
- VNVA is opened (green).
- Confirm via the "ODH" HMI page that
- PT-110-N is in 50-65 psi, and
- EV-102-N and EV-105-N are closed.
- Confirm at the outside LN2 tank that
- LN2 Tank is above 10 inwc (If it is below 24 inwc, then follow the steps on ... page for a refill), and
- HCV-13 is opened properly (ask the Target Expert on shift whether it was changed recently).
- Note down the start time and the initial level for the elog entry.
Procedure
Precooling Phase
- Open EV-200-N via ODH HMI page.
- Open EV-100-N via ODH HMI page.
- Monitor TE-104-N and TE-109-N, and ensure they continue to fall to below 95K. This should take 5-10 minutes.
- Look at the scaled values.
Filling Phase
You should be ready to switch the HMI pages between "Purifier LN2 Overview" and "ODH" quickly:
- When temperatures reach ~90K, Open VNFA via the purifier overview HMI page, and immediately move to the next step.
- Immediately close EV-200-N.
- Monitor purifier level A and PTA via purifier overview LN2 page on HMI.
- If PTA goes above 8 psig, close EV-100-N.
- When level A reaches 90%, close EV-100-N.
- Open EV-200-N.
- Close VNFA.
- Confirm that Level A and PTA are not increasing.
- If needing to fill LN2 shield, then transition to that procedure. If LN2 shield does not need to be filled, then leave EV-200-N opened until the transfer line warms up (check TE-104,109 after ~4hrs and then close EV-200-N).
- Note down the finish time and the final level for the elog entry.
- Post a Fermilab elog entry regarding this fill (see the past elog entries for the format).