1 07/09/2004Rack Coordination meeting Ph.Gavillet CERN/PH-LBO PC Racks - Status Content qNews, matters arising ãLast Experiment meeting (24/08) – Minutes to come ãPresentation at the 10th Elect. Workshop for LHC (Boston /09): åF.Wickens draft talk on: åFeed back on content, author list,.. (Experiments, PH-ESS, TS-EL) ãExperiment status (Y.E: Atlas, A.R: CMS, Ph.G: LHCb, Alice: ?) qTowards to actually install PC racks : ãReview of experiment's milestones ãRackcoolers ordering ãPowering, packaging,.. solutions

2 07/09/2004Rack Coordination meeting Ph.Gavillet CERN/PH-LBO Status of LHCb PC Farm prototype PC rack configuration 2 * Subfarm / 59U rack Each rack 1 * rackcooler CIAT 1 elec. Dist. box (1phase :63A) 1 * 48-port Control switch Each Subfarm 3 * 9-outlet reglettes (16A) 23 * PCs 1 * 24-port Data switch

3 07/09/2004Rack Coordination meeting Ph.Gavillet CERN/PH-LBO Status of LHCb PC Farm prototype Powering tests (06/07) qTS-EL (J.Pierlot) ãTest 1: TDM drawer: 63A on each phase - Circuit breaker (60A, C-curve) åPC rack powered on one phase only å6 departs supplying one reglette each (10A, 9 outlets) åOne (16A, C-curve) circuit breaker / depart åResults: OK, as long as the off time of the PCs is short (< a few mins) Explanation: after a short shutoff the various capacitors are still partially loaded hence the inrush extra current is lower ãTest2: TDM circuit breaker (60A, D-curve) åResults: OK repeatedly åD-curve would protect up to 10*In (~600A) inrush current ãConclusion: current Farm prototype can be powered in one go

4 07/09/2004Rack Coordination meeting Ph.Gavillet CERN/PH-LBO Status of LHCb PC Farm prototype Characterization of LV supply (K.Kahle) qLV measurements (06/08: K.Kahle, J.Pierlot-TS-EL) ãMeasurements of new PC types (Melrow) å2.8 GHz: W, 3.06 GHz: 270W åFeatures: new PWS type from Zippy, Delta (China) (IBM,..) åResults (preliminary) New PCs show similar inrush current (<20A) ãFull rack measurement åAt power up åAt 100% CPU load ãTS-EL Technical note to be issued

5 07/09/2004Rack Coordination meeting Ph.Gavillet CERN/PH-LBO Status of LHCb PC Farm prototype Outlook (short term) qFollow up of LV ãGet recommendations from K.Kahle’s report ãWork out with TS-EL specifications of LV supply åTransformer åCircuit breaker protection åNeutral rating qComplete cooling measurements on full configuration ãPower in / Power out balance ãMap of temperatures: In / behind PCs / Out

6 07/09/2004Rack Coordination meeting Ph.Gavillet CERN/PH-LBO Towards actually installing PC racks Experiment’s milestones / Ordering of equipment qReview experiments milestones ãInstallation of PC racks from Spring 2005 on qInformation from CIAT ãPrice quotation for rackcooler (alone, rack included) ãReview of specifications: ~ 3 weeks (17/09/04) ãPrice enquiry:~ 5-6 weeks ãFabrication:~ 5-6 weeks ãDelivery: per batch of units ãActual rack installation/test ~ 2-3 weeks qPowering, packaging,.. common solutions ãSeems more experiment specific åDifferent rack size i.e # number of PCs / rackpowering schemes åDifferent access constraints ãCommon contacts to industry (PGEP,..) ãKeep exchanging all useful infos