CAT Chat Minutes

November 10, 2000


Information and Follow-up Items

1. What was the outcome with last weeks horizontal instability?

An adjustment was made to RF system #2 on the klystron input, which eliminated the problem.

2.  On Friday, November 3, the beam came up with gaps fully closed. What happened?

At the beginning of every new run, we close the gaps fully to check the orbit and subsequent to shutter permit the gaps are fully opened. However at the beginning of this run the gaps were opened using global open from user mode prior to shutter permit. The fully closed values were stored as the value to return to next time. When the beam dump happened on Friday for unknown reasons, the global open was not automatic. The operators have to open it manually. However when doing so the device was already in Operator mode and so the last gap value was not stored. Upon completion of injection the devices were told to close and they returned to values, which were stored from a previous global open. We are currently looking at how to avoid such mistakes in the future. One possibility is not to close the device at all and expect the beamlines to act on it. We strongly urge the CATS to start addressing the issue of checking the undulator gaps prior to start of every fill.  

3.  With regards to the undulator, how do I set a minimum limit on the gap?

The beamline operations limit process variable (IDxx:DeviceLimit.VAL) is meant for such use. The process variable is set by a floor coordinator at the request of the beamline staff as a protection for beamline equipment.

4.  Two fire alarms took place last week, one on Friday and the others this past Sunday. What were the causes? Also, when the alarm goes off, can we stay in the LOM instead of going outside?

A failure of the EMW power supply was the cause for the fire alarm on Friday. Sundays incident turned out to be another power supply problem.  If a fire alarm occurs in the experiment hall, staying in the LOM area is fine. Fire zones separate the buildings and firebreaks separate each zone. The wall between the LOM and the experiment floor is a firebreak. This is the reason that the doors to the labs should remain closed when not in use.

Glen Decker reported last weeks percentage of availability at about 97%. Eight beam losses occurred with six associated with injection.

A 48-hour studies period will begin on Monday, November 13.

General Information

The operating beam parameters are now displayed on our TV system. The PVs have been changed from the last run. Once finalized new names will be provided. A 24-hour history plot is still available on the web.

A workshop on "Multiple Beamlines from a Single Insertion Point" will take place on Friday, November 17, 2000 from 8:30 a.m. to 4:00 pm in Rooms E1100/E1200 in Building 402. If youre interested in attending this workshop, please e-mail Susan Strasser at: