26/09/2007 martin.gastal@cern.ch 1

CMS Area Working Group Meeting

26/09/2007 martin.gastal@cern.ch 2

Emergency (AUG) stops systems in CMS underground areas

→Goal: To have 2 separate AUG networks→UXC55→USC55 (no exception for LHC or Magnet areas)→Avoid fast discharge of Magnet

→Implications: →Emergency stops in UXC55 must cut power on equipment

located in the UXC55 even if the power comes from the USC55→A list of such devices has been drafted but needs to be

completed:→Coil racks in X4Near balcony→Magnet diffusion pumps on YB0→All types of AI, He return heaters→Vacuum sensors, combined gauges(>1000V)

→Related issue→The grounding scheme of the experiment might be compromised

if unfiltered power is used on devices located on YB0 (ie pumps)→G Perinic & B Cure are to send their grounding schemes to S

Lusin

26/09/2007 martin.gastal@cern.ch 3

UXC55 Racks: X2 Near Side

2 coil racks will be powered on the LV network

26/09/2007 martin.gastal@cern.ch 4

Emergency (AUG) stops systems in CMS underground areas

→Suggestions by TS-EL:→Do not cut UPS power networks by AUG (red strips to be

applies)→Use equipment stops (or similar means) on racks no connected

to AUG→Install AULs in the laser room that is considered as a separate

building. Activating these devices will not generate an alarm and call the fire brigade

→Install a hardware switch at substation level to shut down the whole underground area (from CMS CR)

→Use the LV network to power devices in UXC55 when appropriate

→Filtered power (grounding issue addressed)→Network cut by AUGs in UXC55

→Ok for coil racks- need to be connect to 230V contactors →For other devices such as diffusion pumps, sensors, R Lassausaie

proposed scheme has been endorsed (see his presentation)

26/09/2007 martin.gastal@cern.ch 5

→IT racks in USC55 to be protected by AUL

→How it should be

26/09/2007 martin.gastal@cern.ch 6

Présentation des installations de contrôle et de sécurité de l’aimant CMS (by N Bourgeois)

Supply arrangement and AUG/AUL actions

1 2 3 4 5 6 7 8 9

Dessiné par : N.Bourgeois

Folio suivant : 3

Magnet Control SystèmMise à jour : 02/02/2007

FULL FILENAME\\CERN.CH\DFS\USERS\B\BOURGEOI\EXPERIENCES\CMS\230V 400V\BPEOPT5 DEFINITF.VSD

PAGE

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Table

CP1CP2

MC

S

MS

S

E D

01

07

01

DCCT

S4C02S4A01

S4L01

48V dc

07

Arm

oire

Arm

oire

Arm

oire

Reseau assuré (diesel)

Reseau UPS

Reseau Normal

Tres Basse Tension USC55

Zone S4

UXC55 Pompes à diffusion

Rack Saclay

USC55 Zone S3

Alimentation S3B01

SDX 55Cde CR

Cde CP

26/09/2007 martin.gastal@cern.ch 7

Emergency (AUG) stops systems in CMS underground areas

→Actions to take to be ready for a general test on 15/02/2008:→Issue a document synthesising the position of AUGs in USC55

and UXC55 (R Lassausaie)→Review of document by Safety coordinator (M Arnaud), and

GLIMOS (C Schaefer)→Execute work (INEO)→Organise reception & tests (G Cumer)