In this mode, the fridge level should be maintained above the 'Heat Exchanger Bottom' (see the Purple curve on the top-left graph of the screenshot below), and the separator is kept at cold with 20slm return flow. IMPORTANT: If you see the Heat-Ex Top resistance (purple curve) starts increasing, then reduce the number of turns on the fridge run-valve using the "Fridge Valve Panel" VI on the CCP
Configuration / Things to maintain
| Sub-system | Status |
|---|---|
| Microwaves | ON |
| NMR | Taking Data |
| Fridge | All roots pumps are running Adjust fridge RUN/Bypass valve to keep the fridge LHe level |
| Magnet | Ensure the magnet has enough LHe. Discuss with the Target Expert when to implement Switching from Production Mode to Hold Mode Ensure Magnet LN2 level is above 50%, if not refill it. |
| QT System | Ensure the purifier LN2 level is above 50%, if not refill it. |
Outlet FlowsOutlet Flows (nominal)
| Outlet Flow (in slm) | Run Valve / Bypass Valve | How to check and control | |
|---|---|---|---|
| Fridge | Nominal 45slm (can be higher (depends on the microwave power + beam) | Fridge Run valve → 1 turn Bypass valve → CLOSED | How to control the Fridge Return flow |
| Separator | 20 | N/A | How to control the Separator Return flow |
| Magnet | ~7 (on pressure PID at 0.9 psi) | N/A | (link to a page) |
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