1. High Voltage System outside Drawers Tilecal upgrade meeting at Stockholm (3-5 June 2013) François Vazeille on behalf of Roméo Bonnefoy, Christian Fayard, Marie-Lise Mercier, Eric Sahuc.  Summary of previous progresses  Present status  Tests and next steps 1

2. Summary of previous progresses  Several options reported since a long time HV regulation inside/outside Drawers [Tilecal meetings: February 2008, November 2009, September 2012]  Choice of the outside option 3: - Re-cycling of HV cards inside a special crate put in the electronics room. - Design of HV bus cards sharing the individual HV’s (with noise killers). - Use of multiconductor cables to supply the HV bus cards.  Clermont-Ferrand proposition to develop an outside option, but ready to provide all the information on the present ATLAS inside option. 2

3. New HV Bus boards (no active components) 12 channels. - A 4-layer printed circuit: External layers as shielding, Internal layers to distribute the HVs. - Noise killers everywhere. - New HV connectors (more robust), but 8 weeks delivery delay New HV regulation crate: ¼ of the total space (4 Modules later) HV LV’s Individual Hvout: SUBD25 connectors CANBUS Rear Front 3

4. Present status HV Bus boards ready to equip 3 trains of Mini-Drawers A cable tray will run 3 different cable lengths towards Drawers 2, 3 and 4 (Fixation holes made here) 4

5. Regulation crate HV Source Operational DCS Various cable lengths - 1m long. - 4 times 20 m long (175) - 100 m long, to reproduce ATLAS. 5

6. Tests and next steps  Clermont-Ferrand tests HV tests in progress, with a PMT Block lighted by a blue LED  Noise measurements for different cable lengths.  Results the next time.  CERN tests - Mini-Drawer handling/connection tests in building 175 using Slider and Basket, in the same time as mechanics tests. - HV tests in building 175, once the Clermont-Fd tests will be fully efficient. - Equipment of a Demonstrator in Building 175. 6