The LUCI1 1.5/2.0 Longslit mask experienced a MOS mask failure moving from turnout to FPU.  During this failure the mask rotator failed to move and the mask stuck in an intermediate state.  This MOS error could be caused by loose screws on the mask frame, or the “OPEN” position has shifted.  Investigations are ongoing.  LUCI1 is out of service until this is resolved.

UT20220331 – The motor currents were adjusted and the unit put back in service with no restrictions