Problematic channel's log

Section/X/Y Time period of malfunction Problem description
O/60/32...O/60/57 29.04.08 8:50 - ??? Short circuit in power line 32/6 (+6V LV chains)

Cells with (presumably) damaged optical fibers of LED Monitoring system

In these cells week or absent LED signal is observed.

Side Section/X/Y R/O Crate/Slot/Channel Comment
C O/17/16 10/02/17  
O/18/17 10/02/26  
O/01/56 08/18/17  
O/31/57 10/20/31  
O/08/55 09/18/08  
A I/55/44 15/17/23  
I/32/14 15/02/00  
I/33/14 15/02/01  
I/32/16 15/02/16  
I/55/35 15/13/15  
I/55/36 15/13/23  
I/50/38 15/14/02  
O/37/21 19/03/29  
I/53/32...I 55/34 15/12/(21..23;29..31 and 15/13/(5..7) LED A3.11.4...entire bundle is damaged
I/53/38...55/40 15/14/(5..7;13..15;21..23) LED A3.08.4, entire bundle is damaged
O/36/54...39/57 19/14/(4..7; 12..15; 20..23; 28..31) LED A1.05.1...entire bundle is damaged

Power supplies

ECAL exploits two types of power supplies:

  • low voltages (LV) are provided by MARATON power supplies located in the racks L3B01 (C-side) and L3B11 (A-side) on the platform on top of the detector;
  • medium voltages (MV) are provided by AGILENT power supply located in the barrack;

Operating rules:

  • Avoid unnecessary switching-on/switching-off of power supplies, especially - the MARATON ones;
  • After power cut: do not turn on low voltages immediately, but wait about 30 minutes - one hour;
  • In case of emergency shut-down: MV (AGILENT) should be turned off first. After that LV (MARATON) can be turned off, but not contra vise;
  • Each switching-on / switching-off of LV (MARATON) should be mentioned in CALO logbook together with the status of AGILENT power supply;

  • Correct procedure for complete shut down of the ECAL:
  1. Set zero high voltage (HV) codes on ECAL photomultipliers. Wait for confirmation from ECS software;
  2. Set zero LED intensity codes. Wait for confirmation from ECS software;
  3. Set zero medium voltages on Agilent power supply. Wait for confirmation from ECS software;
  4. Switch off low voltages. All four dedicated channels of MARATON power supply must be turned off at once;

  • Correct procedure to turn on the ECAL:

  1. Switch on low voltages. All four dedicated channels of MARATON power supply must be turned on at once.
    DO NOT TURN ON single channel, it can cause MARATON supply failure. In case of alarms / warnings, indicating 'short-circuits' in LV lines (a) make notice in CALO logbook and (b) contact experts;
  2. Enable high voltage on ECAL photomultipliers. By default it is disabled by overcurrent protection circuits. Protection can be removed by means of ECS software;
  3. Turn on medium voltages on Agilent power supply. Wait for confirmation from ECS software;
  4. Configure high voltages on ECAL photomultipliers. Do not exceed marginal gain value 3x10^5 . Configuration can take several minutes. When it is finished, check the status of overcurrent protection circuits. In case of alarms / warnings (a) make notice in CALO logbook and (b) contact experts;
  5. Configure intensities of ECAL LEDs;

Nominal settings and typical values for current consumption:

  • Low voltages (MARATON)
Side Rack Supply channel Voltage Current, no MV Current, Nominal MV Comment
C L3B01 1 +6.95V 10.0A 9.8A  
2 +6.98V 13.4A 12.9A  
3 -6.8V 16A 16A  
4 14.9V 5A 5A Shared with PS, consumption may vary
A L3B11 1 +7.0V 12.0A 11.6A  
2 +7.0V 11.9A 11.5A  
3 -6.88V 16A 16A  
4 15.0V 7A 7A Shared with PS, consumption may vary

  • Medium voltages (AGILENT) for phototubes

Side Supply channel Voltage Current, no MV Current, Nominal MV, PM HV=0 Current, Nominal MV, Nominal PM HV
C 3 80V 0.2A 0.48A 1.39A
A 1 80V 0.2A 0.49A 1.39A

Voltage distribution / control boxes

Side, PC SPECS master address Control box # SPECS slave address Serial number
C, ECHVC01W 18 (EHV5) 01 01 08
02 02 44
03 03 40
04 04 03
17(EHV4) 05 05 16
06 06 45
07 07 33
08 08 25
19(EHV6) 09 09 34
10 10 09
11 11 31
12 12 26
20(EHV7) 13 13 30
14 14 19
15 15 21
16 16 17
A, ECHVA01W 19(EHV2) 17 17 34
18 18 20
19 19 28
20 20 06
18(EHV1) 21 21 27
22 22 36
23 23 35
24 24 11
17(EHV0) 25 25 23
26 26 29
27 27 13
28 28 18
20(EHV3) 29 29 10
30 31 41
31 32 46
32 01 38

-- IrinaMachikhiliyan - 25 Apr 2008


This topic: LHCb > LHCbCalo > LHCbCaloEcal
Topic revision: r3 - 2008-04-29 - IrinaMachikhiliyan
 
This site is powered by the TWiki collaboration platform Powered by PerlCopyright & 2008-2019 by the contributing authors. All material on this collaboration platform is the property of the contributing authors.
Ideas, requests, problems regarding TWiki? Send feedback