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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


If the system is currently on Hold Mode, then you can follow the steps for Transitioning from the Hold mode to the Production Mode


Configuration / Things to maintain

MicrowavesON. (link a page with instructions how to adjust/control specifically for this mode)
NMRTaking Data
FridgeAll roots pumps are running
Adjust fridge RUN/Bypass valve to keep the fridge LHe level
MagnetEnsure 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 SystemEnsure the purifier LN2 level is above 50%, if not refill it.
Ensure both liquefiers are producing LHe with the rate of ~ 4 L/ hr.



Outlet Flows


Outlet Flow (in slm)Run Valve / Bypass ValveHow to check and control
Fridge       Nominal 45slm
(depends on the microwave power + beam)		Fridge Run valve → 0.5 turns
Bypass valve → CLOSED		How to control the Fridge Return flow
Separator       20 N/AHow to control the Separator Return flow
Magnet     ~7 (on pressure PID at 0.9 psi)N/A(link to a page)

Transitioning from the Production Mode to the Hold Mode

Conditions:

  1. Fridge parameters & valve positions when the fridge is in Production Mode
  2. QT system conditions when the fridge is in Production Mode
  3. Magnet conditions when the fridge is in Production Mode
  4. Cryo-control (CCP) parameters / conditions when the fridge is in Production Mode
  5. Microwave parameters / conditions when the fridge is in Production Mode
  6. Target Lifter conditions when the fridge is in Production Mode
  7. UVA-NMR conditions when the fridge is in Production Mode 
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