On Thursday May 11th operators attempted to move the T2 profile monitor (T2-MK2) to the IN position but were unsuccessful. The monitor would leave the OUT limit, but would not reach the IN limit. This was repeated 2 times. The air amplifier was inspected and nothing out of the ordinary was noted. The T1 profile monitor was tested and was working properly. At the time it was suspected that the monitor cassette had become dislodged as occurred earlier this running period (see E-Log #221).
Today monitor actuation was attempted again and it moved to the IN position normally, this was done a total of 3 times.. An electronic check was performed by Mike Russell who reported that it looked the same as when he last checked, meaning the monitor cassette was definitely not unplugged. The monitor was then used with beam and Eric Chapman reported that monitor was functioning normally. With the beam spot centered vertically on the profile monitor the protect monitor showed more beam on the lower plate, which is expected because the protect monitor center is 2-3mm higher than the profile monitor center (see E-Log #220).
It is unknown why it would not actuate properly last week, but seems to be fine now. Cyclotron fault #9928 has been returned. |