Note to target operators

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User name jpchen

Log entry time 17:51:38 on November 4,2009

Entry number 297395

keyword=Note to target operators

Notice to Target Operator:

Loop 1 has LD2 target operating at 22K and 25 psi.
Due to the very high cooling power requirement, we are using 4K coolant directly from CHL, Deuterium has a frozen point of 19K.
There is a potential of freezing the target if the high power heater not function properly or goes to zero during ioc reboot.
1) When you see the temperature drops significantly, it probably is an indication that we do not have enough heating power (either from beam or high power heater), which probably indicates that the PID control of high power heater is not working properly. In this case, you should use the local heater poper supply in the middle room (top one is for loop 1) to keep temperature drop too much.
If the local heat power supply also fails, you should reduce the coolant supply by closing down the J-T valve (at a rate of 2% per minute). Always be gentle when adjust J-T valve, too fast could cause cryo-crashing.
2) When reboot ioc, make sure you use the local heater power supply in the middel room (top one) before starting ioc reboot.

Also please respect the alarm. If there is an alarm and you don't know how to deal with it, please call the target-on-call.