“Breve” stato dell’apparato:Risultati e ProblemiAnton, Ian, Nicolas, Saleh, Salvatore

• Barrel• Endcap• Endcap Cooling• Last Minute ….

Domenica !!?..neanche a bergamo alta

Barrel

HV&LV problems

• LV barrel: Lost of threshold control due to FEB or DB problem - near 3% of chambers per wheel (apart from W+1 which is fine)

• HV barrel: several chambers in SG (~3-4), several cables from the cable chain broken (~10), several P.S distributors broken (~4-5), several chamber with high current (~2-3). A dedicated excel file is being prepared with all HV problem types. Once available and updated all the numbers and exact names will be known.

Noise Study:Performed Actions

A. Hardware Interventions Star washers Multiple grounding Copper tape (for better connectivity to ground) Additional RPC Shielding External HV&LV system Improving grounding (capacitors + shortening LVDS

shielding cables + additional ground to iron) LV power supply instabilities checked (7 modules repaired)B. Software Interventions Reducing noise by setting threshold and masking

Noise Problems• There are two main problems:

1. Coherent noise2. Noise Fluctuation in time

• Still to be done…1. Test new procedure to set thresholds2. Test new masking procedure

Coherent Noise

Noise Fluctuations

Conclusions

Probably there is no good contact in all ground connection on the front panel since copper tape and alodine improve the chamber performance

Probably there is no good contact between the aluminum covers and the preloaded bars. M.Jonson suggested that capacitive coupling between the top covers and the FEB is the reason for introducing the noise

LV power supply instability sensitive to external disturbance. Good candidate source for coherent noise

Very large spread in threshold settings that could lead to chip self-excitation. Good candidate source for noise fluctuations

Questions/Discussion

Do we monitor the chambers with installed star washers? Do we see any difference?

Do we monitor the chambers with additional AL covers? Do we see any difference?

Do we think yet that the LV power supply instability is sensitive to external disturbance and could be a good candidate source for coherent noise?

Do we know the effect of the shortening of LVDS cables? Can we conclude that the new procedure to set thresholds

have solved our problems in noise fluctuations?

Trigger Interventions

• Change RJ45 connectors in order to improve grounding of CCU rings (14 tower + 4 already done)

• Upgrade CB• Change LAN Trafos with new ones with

magnetic shielding• Fix known problems – YEN1near• Investigate one tower failure during CRAFT09

– RB+1far

Actions do be done

• Terminate the story of swapped signal cables• Action matrix to be fulfilled• Spare list & Spare management• Procedure and names for hardware

interventions during LHC

Endcap

High Voltage

Preparation of the high voltage system for all 3 negative side RPC stations.- Assembly and testing of the HV distribution boxes. (12 for negative Endcap RPCs)

- Installation of hardware in USC. (4 EASY crates, 4 fan units,18 modules)

- Cables connection from DBs to modules. (120 cables)

- Preparation of the Jupiter connectors , connection with DBs and labelling USC.(480 connectors)

- Patch Panel preparation in UXC. (grounding, routing and connection of 216 cables)- HV racks temperatures sensors installation and connection with PP. (12 T sensors).

Problems appeared and present status: -In Total 33 channels tripping problems were seen in both +ve & -ve Endcap RPCs.

23 have been fixed by changing the connector at PP, chambers and DBs sides.

10 still need to be fixed but have been minimized by disconnecting the gaps.

-In Total 16 channels spikes observed

09 have been fixed by changing connectors at PP, chambers and DBs sides.

07 still need to be fixed but have been minimized by disconnecting the gaps.

One side labels from module to EASY crates and routing of the cables in cables tray still to be done.

Low Voltage Preparation of the Low voltage system for all 3 negative side RPC

stations.- Installation of hardware in UXC. (6 AC/DC convertor, 6 EASY Crates , 18 LV boards)- Daisy chain preparation of DCS cables from MAO, FEBs , LBBs crates and then to next rack

.(6 racks are in use for –Z side).- Cables connection with LV boards, reparation of APP45 connectors and cables routing . (432

connectors , 108 cables).- Preparation of APP75 for 48V from MAO to Easy crates.(24 plugs)- Preparation of flat ribbon cables with 50 pins connectors for racks internal daisy chain. (24

cables ).- Installation of branch controllers and mapping of the hardware.

LV Problems:- Negative side ~9 channels tripping problems were seen due to bad connectors of APP45: all

have been fixed.- One MAO broken replaced with spare.- In Total 8LV boards gave problems during last 5 months in whole endcap RPCs system. All

repaired from EP now every thing is fine.- Two new cables are pulled from chambers to racks in RE+3 and RE-1.

Readout System

Connections at both side (chambers and link board side) already done during pre-commissioning.

For commissioning during connectivity and threshold scan test following problems observed.

- 6 faulty FEBs replaced with new ones from different stations.

- I2C problems seen in some chambers, many solved but 4 still to be done.

- Many swap of signal cables seen at LBBs and Chambers level all have been solved.

Gas System• Gas leak search performed at all stations.• In 3 sectors open gas circuits detected which have been fixed. (2 in RE-3 and 1

in RE-1)• In 5 sectors big leak (500 to 1300ml/h in approx. 18 L volume) is observed . In

4 sectors leaks have been fixed. One at RE+2 still to be cured (problem in access time).

• Modified 6 chambers of one gas sectors from one gas in/out to two in/out at RE+2 and made this sector semi parallel 10degree.

• Total 6 sectors made semi parallel with respect to gas by using custom gas distribution boxes at RE+2.

• Bad calibrated gas flow cells have been changed and cells have been equalized.

• Gas racks flow cells have been labelled. • 64 Gas Humidity sensors have been installed on gas pipes (48 in the barrel)• 87 T sensors have been installed

Temperature/Humidity sensors

Campaign to equip the Endcap RPCs with temperature sensors have been almost ended as the original plan (1 sensor each 6 chambers).

T is a key element to monitor. Additional sensors needed to monitor T in all chambers like in RB

- Each station has 12 temperature sensors at the chambers with 60degree gap. For six station we have 72 sensors.

- 4 humidity sensors have been installed at each disk to read the environmental humidity. Total for six stations there are 24 humidity sensors.

- On +Z endcap 4 temperature sensors at coolant have been installed at each station (12 sensors in total).

- On –Z endcap, 3 sensors have been installed in this week in the accessible zones with CMS closed.

- Every thing has been implemented in PVSS and data can be recorded.

+ the circuit

The RH SENSOR:HIH-4000 Honeywell

The ADC

CAEN A3801A 128 Channel Temp. Sensor Board(-45 °C +125 °C)

AD592–SPECIFICATIONSAD592CNACCURACY typical maximumCalibration Error @ +25°C : 0.3 0.5 °CError over Temperature : 0.4 1.0 °CNonlinearity : 0.1 0.35°C

The T sensor AD592CN Analog Devices

Sensor Construction and assembly done in Pavia (circuits and plastic cases), mechanics for gas pipes done in Naples - R. Guida coordination

Installation: Roberto, Ian, Nicolas, SashaMapping and read out: Nicolas and Giovanni

RH sensors on the disks: 4 RH sensors per disk(far, near, north, south) =24 sensorsRH sensors on the gas line (supply, return) : 4 per disk + 8 per wheel = 64 sensorsT sensors on the chambers : 12 per disk (6 ch of the inner ring + 6 ch of the outer ring) =72 sensorsT sensors on the RE-cooling pipes : +side (supply & return): 2 cooling sectors per disk =2 x2 x3 =12 sensors -side (only supply) : 1 cooling sector per disk (top) = 3 sensors (DONE NOW !)

Endcap Pending Jobs

• 18 chambers are single gap mode: we have to find the problematic points and solutions in P5.

• In one gas sector of RE+2 gas leak need to be fixed.• INB labels in HV hardware in USC to be mounted.• INB labels in RE-3 to be mounted.• Plastic coated labels at the modules side and cables routing in cables tray.• 4 i2c problems need to fix.• Cooling circuits to be repaired (5 chambers in RE+1, and 1 in RE-1),

demanding CSC dismounting.• Additional 9 T sensors on cooling water pipes in –Z endcap• Additional 360 T sensors on all chambers in endcaps (now only 12 out of

72 for each disk)

Endcap hardware: Spare status

Hardware Description Quantity in use Spare we have More spare we needed

High Voltage

Modules (A3512N)36 6 0

MAOs(A3485)1 0 1

EASY Crates(EASY3000)8 3 0

Branch Controllers(A1676A)7 0 1

Low Voltage

Modules(A3009)36 2 3

MAOs(A3486S)12 1(A3486) 2 (A3486S)

EASY crates(EASY3000S)12 0 2

128 Channel Temp. ADC Board(A3801A)

4 (2 borrow from barrel) 0 3 have been ordered

Endcap Cooling

16/07/09 : A modification to the Cold Box of the magnet was made to allow a P increase (11.8 to 15.8bar) in the Primary and increase the flow by ~70%

17/07/09 : The set point was increased from 16 to 18 deg allowing the regulator valve to close so giving some control over the system

23/07/09 :Beginning of the CRAFT

27/07/09 : The set point was decreased from 18 to 17 deg, since the regulator valve remained all the time 100% open until the end of the craft

Temperature variations of the Secondary Cooling Circuit

(week 29)

Set point change from 16 -18deg C

Increase in primary pressure from 11.8 to 15.8 bar. Flow up by >70%

MWGR

16deg C Set point

17/07/09 ~3pm

18 deg C Set point

Tsup=17.9, Tret=19

T Secondary Cooling Circuit

27/07/09 ~13:00

17 deg C Set point

Tsup=17.2, Tret=18.4

Reg Valve ~ 100%

18 deg C Set point, Regulation Valve 65%

Increase in primary pressure from 11.8 to 15.8 bar. Flow up by >70%

craft

Febs Off

Set point =18 deg

Set point =17 deg

Set point =18 deg

Weeks of GR Feb OffBeginning of Crfaft 30 , system on until

30 Aug 09

Up till 16 July 09 17 July to 23 July 23 July to 27 July 27 July to today

EN1_

R2_C

01

4 periods :

EN1_R2_C01

Coolant Probes EP2

27th of July at 13:00 : change in setpoint the End-Cap circuit the supply temperature is 17.2C - return temperature 18.4C, >valve position 100%.

<I > /disk

27th of July at 13:00 : change in setpoint the End-Cap circuit the supply temperature is 17.2C - return temperature 18.4C, >valve position 100%.

Currents ~ stablesCurrents ~ increasing

Weeks of GR NO GRBeginning of Crfaft 30 , system on until 30

Aug 09Up till 16 July 09 17 July to 23 July 23 July to 27 July 27 July to today

Set Point 16deg C 18degC 18degC 17degC

Valve regulation 100% 65% 100%

Temp Supply USC Oscillating 18degC 17.2/17.3

Temp water @ RE+1 (UXC) 19.9 x

19.6 18.7Temp water @ RE+2 (UXC) 19.5 x 19.05 18.15

Temp of Chambe RE+1 Oscillating 19.3 19.9 19.3Temp of Chambe RE+2 Oscillating 20.5 21 20.6Temp of Chambe RE+3 Oscillating 20.75 21.4 21

20.1 20.7 20.3Temp of Chambe RE-3 Oscillating 21.9 22.6 22.2Temp of Chambe RE-2 Oscillating 21.3 22 21.6Temp of Chambe RE-1 Oscillating 21 21.75 21.1

21.4 22.1 21.6

We require additional interventions to secure: T chambers <20 deg for both endcaps with valve @ 50%

Last minute …..

Endcap LB and CB access with CMS closed

Endcap LB and CB access with CMS closed