After extensive testing over the last 2 weeks it was determined that the protect monitor on the T1-MK2 target had an issue with intermittent shorting between the high voltage line and ground (movement of the target ladder was causing the short to come and go).

On the May 21 maintenance day the T1-MK2 target was moved from the beamline to the hot cell (102mSv/hr @ 0.5m).  The T1-MK1 target was then moved from Storage Pit location #3 to the beam line (as in the past, alignment of the flask to the #3 position hole was challenging, and the flask had to be suspended above the alignment pins to achieve alignment with the hole - In the future this storage pit location should be avoided).

Cameras were mounted on the T1 alignment frame for remote viewing of alignment with the hole as well as flask door position and hook latch position.  The camera locations chosen provided useful views and did not interfere with the target or frame.  After procurement of additional mounting brackets the cameras will be permanently installed at these locations (already completed on the T2 frame).

The target moves were completed successfully, vacuum pump-down was normal, and electrical checks of the T1-MK1 profile monitor and protect monitor were normal.  When start-up of the cooling system was attempted problems were encountered with the control system.  Multiple channels on the digital output module were shorting, causing the power supply fuse in the PLC cabinet to blow.  This was eventually tracked down to two damaged cables (B1A:T1CS:SVSEC and B1A:T1:SVCOL) which somehow had been crushed during removal of shielding.  The cables were replaced and all cables secured as much as possible in the vertical chase leading up from T1.  After replacing the cables we discovered that the digital output for the SVSEC signal was stuck in 'drive' status.  The module was replaced and then the control system was working normally (approximately 11am on May 23rd).

The T1 cooling system was started (no change to 1ACG2 vacuum), ladder movement through all target positions was tested, and profile monitor actuation was tested.  Updated target info sheets were submitted to Ops (attached in PDF format) and XTPAGE 7L was updated.

Diagnosis and repair of the T1-MK2 target will take place in the hot cell over the coming weeks.

Cyclotron Fault #12266 was returned.