ESS spoke CM 02 weekly meeting 20201102 Han

ESS spoke CM 02 weekly meeting 20201102 Han Li

Coupler conditioning Conditioning program> Use arc detector and e- pick up. Frequency using for off resonance conditioning at warm: 353 MHz Auto-conditioning 24/7 Criteria for FPC conditioning ready : outgassing lower than 3 E-7 mbar (vacuum baseline 1 E-7 mbar) Parameter Loop control time (s) Pulse repeat rate (Hz) Vacuum upper limit (mbar) value 1 14 5 e-6 Vacuum lower limit (mbar) Initial pulse length (µs) pulse length step 1 e-6 50 50 µs, 100µs, 250µs, 500 µs, 1 ms, 2 ms, 3. 5 ms Vacuum hardware interlock (mbar) e- pickup interlock (m. A) 1 e-5 2 Main Parameters of Spoke FPC Conditioning 2 2

Coupler conditioning conclusion FPC 1 & 2 Real time [h] Intervention Up time [h] Down time [h] Warm 120 2 89. 5 30. 5 Two FPCs are conditioned simultaneously with two pumping carts Three MP bands: 70 d. Bm (10 k. W), 74 d. Bm and 76 d. Bm (40 k. W) CM comparison: Total conditioning timing is about 4 weeks (real time), can be improved to 7 days (based on live time) or even 3 days if conditioning two couplers simultaneously 2 nd CM FPC warm conditioning last about 4 days, is consistent with prototype estimation

Investigation of downtimes Ø Major bottleneck: Stable operation of two RF stations Cause of downtime [h] cause of RF station downtime technical intervetion 2% circulator 15% LLRF; 7 RF station 83% technical intervetion RF station Esys trip ; 12 DB trip; 6 circulator Esys trip DB trip LLRF

Cool down Ø Ø Control valve for safety VB insolation vacuum LN cooldown start from Wednesday LHe cooldown to 4 K

Preliminary time plan Test item time CM installation 26 th-30 th Oct. Preparation 2 nd – 4 th Nov. Install cavity vacuum pump group /water cooling system FPC warm conditioning 5 nd-10 th Nov. 1) Simultaneously 2) Could be prolonged depended on the progressing CM cooldown to 4 K 11 th-12 th Nov. FPC cold conditioning 13 th Nov. CM cooldown to 2 K 16 th Nov. Cavity tuning 17 th Nov. CTS measurement Cavity conditioning (on resonance) 18 th -20 th Nov. Open loop Heat load/Q measurement comment Simultaneously 1)Each cavity 2) PID Long-term stability 23 rd Nov. Piezo compensation 24 th – 27 th Nov. First CM only Warm up 28 th Nov.

Shift for CM test Ø Operation related to FPC conditioning: Auto-conditioning 24/7 Ø Operation related to cavity RF test at cold : only during working hour Working group RF test LLRF High power station Cryogenic Candidate Han Li Akira Miyazaki Konrad Gajewski Kjell E. I. Fransson Tor Lofnes Rolf Wedberg Mykhailo Zhovner Preference working shift Morning shift Afternoon shift (8 a. m. to 4 p. m. ) (1 p. m. to 8 p. m. ) √ Possible for oncall? √ √ √ Tord Peterson Lars Hermansson Esat Pehlivan √