9:30

Ion pumps de-gassed by switching on and off multiple times. Large pressure increase the first time pumps were flashed, pressure recovers quickly once pumps off. Subsequent flashing of ion pumps showed a significantly smaller pressure increase, unitl little increase was seen. 

see http://web-docs.gsi.de/~lestinsk/vacplot.php

Pressure ~3E-8 mbar

10:00

Top NEG controller activated. This controller controls 6 NEG wafers connected in groups of two. NEG wafers connected in two's have the following settings which were utilised in Daresbury

Ramp Time = 45 minutes

Hold Time  = 60 minutes

Vmax =  100 V

Imax =  5A

Pmax = 400W

(See attachment 4)

Settings for the NEG wafers connected in a group of three (white tape on cable) in the moving detector chamber are the same as above but with Pmax = 600W. (See attachment 3)

Settings for the D2000's (kapton tape on cables) are the same used in Daresbury and are;

Ramp Time = 45 minutes

Hold Time  = 60 minutes

Vmax =  65 V

Imax =  3A

Pmax = 254W

Tmax = 500 C

(See attachment 1 and 2)

11:44 

Activation of first set of NEG's completed. The temperature of internal thermocouples went above 150C during activation so power to NEG elements was reduced during activation to 125W per module. NEG's fully OFF to allow internal temperatures to cool. Modules will be activated alone to try and find way of activating NEG's without high temperatures. 

Current bakeout temperature is 95C

Pressure ~ 8E-9 mbar

13:10

All NEG's off. Bakeout Temperature is 95C, internal temperature are ~102C.

Pressure  = 5.8E-10 mbar

Activating a single D2000 NEG pump as they contain in built thermocouples to gauge the effect on internal temperatures. 

14:53

Activation complete for single D2000 up to 500C. Most internal thermocouples remained <110C during activation with one going up to 140C. Temperature of internal thermocouples largely unaffected by the NEG activation untill above 400C NEG temperature. D2000 element will be maintained at 250C for activation of other elements. 

Internal temperatures fallen back to ~102C

Pressure <4E-10 mbar

Would recommend activating elements one at a time with a 20-30 minute ramp and limiting power for NEG modules to ~100W per module.