CAT Chat Minutes

November 26, 2001


Information and Follow-up Items

Recently, the front-end shutters had closed unexpectedly for Sector 5. Why did this take place?

Please let us know the times of the events and we will check the data loggers to see if we can find any recorded reason for the faults. Many, but not all, of the items that can cause the shutters to close are logged and may indicate the cause.

Repeatedly, Sector 14 is losing access to the undulator controls. This problem causes the undulator to be down for 10-20 minutes and we are unable to run during that time. When will this be corrected?

The problem is due to an unanticipated interaction between new linear encoder interface hardware and the latest ID control software. A momentary "glitch" in encoder data causes the control software to latch into "System Manager" access mode (to prevent ID operation after an encoder malfunction). A work-around using the rotary encoders has been implemented. The problem will be fixed in the January shutdown.


User Operations

The storage ring had a period of ~ 75 hours of uninterrupted beamtime during this past week. Two trips occurred caused by the low level rf and a PSS trip in sector 22.

On November 27, at 2400 hours a 16-hour machine studies period will take place. During that time, shielding verification at low current is planned for HP-Cat, Sector 16. This will begin at 11:00 am until 3:00 pm.


General Information

An injury occurred at one of the CAT beamlines where a user, while working in a beamline, injured his head requiring 12 stitches. Please remind all of your personnel to exercise caution when working on or near beamline components.