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The MV1 valve which is a red box in the back of HR3 will start blinking and close the main recovery path and then it forces helium gas through REG4 (making the horn sound). Closing this valve increases the pressure in the recovery manifold so that PC1 with a spike (usually just to 2 psi or so but less than 4 psi). Building pressure in this space pushes helium to the buffer tank through REG4 and REG3.
Functionality of the cycles in HR3
1. VM1 (red-box valve):
* Controls inlet gHe to the Kaeser Compressor
* Closes if there is no pressure rise of '1 psi' (can be changed on the HR3 PLC Screen) in the buffer tank between the sample time period (there are two parameters: sample time period (mins), sample spacing (mins))
2.
Recursive cycles in fault mode:
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