LabView PDP

Polarization Drops to Zero Inexplicably

Check the Magnetic Field Current. If the current has dropped from 121.825 to about 05.A less, this is a problem is the magnet power supply. Call the expert on call.

LabView locks up or NX window locks up

Follow correct step of PDP Restart Procedure

Cryogenics Panel

LHe Batch Fill valve readback jumps to a very large value, magnet dewar no longer fills.
In this situation the encoder will read a large (>10) value and will reset so this new value will be considered closed on the supply valve. A common indication that this has occurred is if the LHe level in the magnet dewar does not refill automatically. The dewar will not fill because the maximum encoder position on the batch fill loop is less than the new "zeroed" value. Temporary fix: This can be fixed temporarily by disabling the LHe batch fill and manually opening the valve, the new "open" position on the valve will be 2-3 turns greater than what it considers the new "zero" position. When the magnet dewar is filled the valve must manually be closed by setting the encoder position to zero (or any value less than what it considers the new "zero"). To fix this offset an access must be made to reset the encoder position.

LHe in the nose drops to below 10-15
If the LHe level in the nose drops significantly below 55-60 it is an indication that the PID loop in place to maintain the nose level cannot keep up with the heat load on the target. In this situation promptly SHUT OFF MICROWAVES AND CALL MCC TO SHUT OFF BEAM. Allow the PID loop to restore LHe to the nose and determine how the heat load on the nose can be reduced (lower beam current, have a Target Expert decrease the voltage of the microwave power supply).