2. Nikolaos TRIKOUPIS on behalf of TE-CRG-CI CRG-TM for LS2 preparation Preliminary activities of the CI section 25/09/2017
22 Sep 2015
TE/CRG-CI

3. Contents List of activities requiring coordination with other groups.
List of activities requiring coordination within the CRG.
List of activities to be handled by CI with limited external coordination.

4. Activities requiring external support/coordination HV channels: Upgrade of cables and connectors
There are cabling and connectors which are non-conforming to the HV requirements but pass the ELQA tests.
CI proposal to upgrade the long cables (signal cables) and DFB Sub-D connectors of the 600A B/Y which do not satisfy the requirements.
TE/MPE cannot perform such an upgrade on the D-sub connectors for LS2; (they internally validate close to kV).
TE/MPE could consider upgrading only the cabling for LS2 and updating the connectors in the future (is it beneficial?)
Strategy to be discussed and be finalized between TE-CRG, TE-MPE, EN-EL for LS2 or later…

5. Activities requiring external support/coordination
Tasks that require opening the interconnects:
Repair of 11 faulty BS inlet thermometers (TT843/TT847), no redundant.
Repair of 3 faulty BS outlet thermometers (TT843/TT847), currently operating on redundant.
Repair of heater LQATH_20L2_EH847 with fault to ground.
Study: Widespread differences on thermocouple protections on BS heaters
Suspected bad heater/heatsink contacts.
Apply thermal grease?
Possible repair on some very sensitive heaters ~10 units or list from OA.
List of BS TT channels
LBRSB_05R4_TT847 <= might be difficult
LQOAG_22L2_TT847
LBALB_18R8_TT843
LQOBA_26L4_TT847
LBALB_27L4_TT843
LBARB_16R1_TT843
LBARB_17L8_TT843
LBALB_27L5_TT843
LBARB_30R5_TT843
LBARB_27L6_TT843
LBALB_29L3_TT843
QRLAB_19L2_TT943
QRLAA_29R1_TT947
QRLAB_15L1_TT947
Test performed at the LBALB_32L4_EH843 (was not possible to provide more than 36W:
When at cold, directly maximum power 150W-200W was given and the heater could maintain this power.
When ramping down observation of region with increasing ThC reading.

6. Activities to be handled by CRG
Tasks requiring coordination within the CRG group:
Repair of 7 non-functional pressure sensors of QRL Line D PT991.
Checking leak tightness of PT sensor manifolds.
Opportunistic repair of >10 faulty TTs in QRL and DFBs.
Repair of T.B.D. by OA list of 10 out of 42 broken QRL heaters 500W.
Repair of 3 faulty LTs (LQASD_27R8_LT811, DFBAL_05R6_LT830, DFBAN_07R7_LT861).
List of damaged QRL & DFB TT channels
DFBMM_04R6_TT830
DFBAD_07R2_TT846
QRLAA_13L5_TT971
QRLBA_09R3_TT971
QRLBA_09L1_TT971
LQTFB_06R7_TT830A
LQYCH_04R1_TT830A
LBRCA_04L5_TT831
QRLAA_13L2_TT961
QRLDG_07L3_TT961
List of damaged 500W RM EH channels
QRLID_03L1_EH990
QRLGC_03R1_EH971A
QRLGC_03R1_EH971B
QRLIB_03R1_EH970B
QRLGE_03R2_EH971B
QRLGD_03L5_EH971B
QRLIA_03R5_EH970B
QRLCD_05L6_EH971A
QRLCC_07L7_EH971B
QRLIA_06R7_EH990

7. Activities to be handled internally by CI
Accuracy measurements on all HV TT channel for detection of partial faulty cards (due to past HV tests).
Accuracy measurements on selected PT sensors.
Possible replacement of aging components on electronic cards.
Preventive maintenance: Identification of faulty cabling/cold solder joints and repair.
Lifetime tests on On/Off mechanical switches
Lifetime tests on power card capacitors (repeat of similar tests performed in 2015).
Install missing backpanel protection cover of crates (multiple cases in RR13, RR53, UA47, USC55, RR77, UA83, …).
Automatic crate recovery after a power-on? example after AUG tests. This requires many changes and currently small benefit; Better to not perform only if OA requires for selected families/locations?
Details on Install missing backpanel protection covers:
RR77.QYC01
RR13.QYC02
RR53.QYC01
USC55.QYC01
Short-circuit while pulling a spare EH cable
damaged all 5 TTs on top level.