1. K.WyllieElectronics meeting 29/05/061 RICH Power Supplies & Grounding Thanks to Johan Morant Paolo Baesso Xavier Le Gouard

2. K.WyllieElectronics meeting 29/05/062 Example: RICH2 module Each module is mechanically and electrically independent. Cooling plate (not shown) grounded. Plastic pipes for insulation

3. K.WyllieElectronics meeting 29/05/063 Power connections & grounding Maraton LV (5V) channel 1 – floating. Tested Maraton LV (5V) channel 2 – floating. Tested CAEN SY1527LC- A1511B Si bias (80V) – floating. Tested ISEG (20kV) – varistor protection. Under test

4. K.WyllieElectronics meeting 29/05/064 Module Power and Grounding Within module – one common ground, connected to safety earth Local ST-4913 regulators few cm from load (L0 + HPD) Regulators enabled/disabled by SPECS slave Allows possibility to enable/disable L0s/HPDs => a ‘gentle’ power-up sequence We power-up with a well-defined sequence for each module: Turn on LV supplies Turn on Si bias Enable regulators for L0/HPDs (SPECS) Enable GOLs on L0 (SPECS) Loop for all L0s in module Filtering of LV, Si bias (and HV) done locally SPECS – shield of cable connected to module ground AND SPECS master ground. No problems seen yet……….

5. K.WyllieElectronics meeting 29/05/065 Tests with Maraton Tested in lab with programmable load Then used in system tests & Frascati testbeams since January

6. K.WyllieElectronics meeting 29/05/066 Hardware 12-channel 6U prototype now in constant use in labs Not yet operated with all channels used (maximum so far is 6 out of 12 = 3 modules) Sense…… looks OK, more tests to be done Tested with proposed grounding scheme – no problems All ‘analog’ settings with potentiometers Needs water cooling – particular connectors for pipes Documentation VERY bad

7. K.WyllieElectronics meeting 29/05/067 Software Tests done with simple user-panel, via USB OPC server from Wiener seems to work (although installation is not obvious…..) Maraton is now networked (same as CAEN system) Now included in PVSS framework Panels/ FSM under development

8. K.WyllieElectronics meeting 29/05/068 Conclusions Power and grounding scheme follows LHCb recommendations Tested successfully with prototype and production modules: System tests in lab since summer 2005 Two testbeams in Frascati Tests on-going, adding final HV system Good experience with Wiener Maraton in system-tests/testbeams