DCS meeting 27.Sep.2002

Serguei Zelepoukine (IHEP, Protvino)

Contents:

1. Front-end electronics: problems & solutions.

2. DCS cabling outside the ECAL detector (CMS integration)

3. Other -- installation matters, the inside ECAL layout, ...

DCS/DSS front-end electronics --- as of beg. September, 2002:

Precision temperature monitoring uses T-MUX as the front-end electronics.T-MUX module includes an analog multiplexer and a transducer, thus providingsignal conditioning for 8-16 channels.

Transducer (RBFE from LHC cryo controls) is RAD-HARD.Analog multiplexer is NOT -- but has been tested with good results in ATLAS.

Proposal: make a multiplexer part changeable and replace it each 2-5 years of operation. This requires T-MUX to be placed outside CMS (on the infrastructure ?).

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This same T-MUX can be used also with DSS temperature sensors.----------------------------------------------------------------------------------------------------------

Humidity monitoring will use the same analog multiplexer part, but a differenttransducer.

RBFE

12x STP cable(to sensors)

DB-25 connectorsDB-25 connectors

AnalogMUX12 chan

Power andcontrol

Outputsignal

Power andcontrol

Outputsignal

Support plate(metal)

TMUX board layoutSerguei Zelepoukine10.Sep.02

Output signals(DB-25 connector)

TMUX boards

Control distribution board

Powerdistributionboard

Support plate

Cable locking

Enclosure (shield)

Serguei Zelepoukine10.Sep.02

T-MUX assembly Output signalsto the counting room

SM_10 SM_9

SM_18 SM_1

T-MUX 1

T-MUX 9

T-MUX 1

T-MUX 9

Temperature monitoring -- T-MUX allocation(only a half of T-MUX assemblies is shown)

T-MUX 10

T-MUX 11

T-MUX 10

T-MUX 11EE

EB

10 sensors per SM (EE)10 sensors per quadrant (EE)

T-MUX has 12 channels --> 1 T-MUX per SM or Quadrant

Each T-MUX has 2 free inputs -- some of them are used for external auxiliary sensors.

S.Zelepoukine 21.Aug.02

Keithley

CMSdetector

A _2

A_1 A_3

A_4

Patchpanel

CavernCountingroom

Patchpanel

T-MUX assembly

T-MUX assemblies -- general layout

Controldistribution

Power supply

Analogsignals

120 m

(top view)

...Controldistribution

Power supply

Sensors

Patch panel

Analog signals(conditioned)Enclosure

T-MUX

S.Zelepoukine 21.Aug.02

DCS/DSS front-end electronics --- as of end. September, 2002:

CMS integration team -- T-MUX assembly can only be placed on balconies (no available space on the CMS surrounding infrastructure). This will extend raw signal paths to ~ 50m (?).

Werner Lustermann --If the front-end electronics can only be placed on balconies -- ELMB can be used as it is used now in H4, with 50 m cables...(To provide SEE protection one can have a redundant ELMB configuration --

2x ELMB are connected to the same set of input signals, but only oneof them is powered and operated. In case of unrecoverable fault it is switched offand the backup ELMB starts running.Two separate CAN buses provide additional redundancy -- for the case ifunrecoverable fault blocks the whole CAN bus.

EP/MIC -- RAD-HARD analog multiplexer (8 channels) design is now in progress. Samples are expected end 2002 -- beg 2003.Seems to be OK for DSS (no high precision required);should be verified for use in precision temperature monitoring.

TMUX Keithleyx 10 x 45

PC45

TMUX Keithleyx 45

PC

45

TMUX

50 m

45

CANELMB

100 m

PC

1

1

4

Detector Balcony Counting room

TMUX Keithleyx 10 x 45

PC45

2

8

3

CANELMB

6 x 10

PC

DCS/DSS cabling and the front-end electronics layout.

Work in progress with the CMS integration team

S.Zelepoukine19.Sep.02

ECAL DCScabling andfront-end electronicslayout

Counting roomCMS

Barrel

Endcap

Barrel

Electronics

ECAL DCS cabling and front-end electronics

Precision temperature monitoring

Humidity monitoring

Cabling:One cable runs from each EB SM (patch panel) and from each EE quadrant to an electronics assembly at a balcony.In total 36 + 8 = 44 cable sections.Cable type is 18x STP (diameter = 12.3 mm; MCA36P, SCEM = 04.21.48.336.5 - 18x2x0.22mm2).

Several additional cables run from different points on CMS (to be defined) to electronics assemblies. These are for auxiliary external sensors; approx. quantity 10-20.Cable type is 1x STP (diameter = 5 mm; MC02P SCEM = 04.21.51.B - 0,22 mm2).

Electronics:4x electronics assemblies are foreseen (see the layout sketch).Each assembly holds several electronic boards and is mounted in a shielded enclosure. Enclosure can be placed in a standard 19” rack, or mounted standalone -- it does not need forced cooling. Approximate size is: width = 19”; height = 30 cm.

Cabling:As for temperature monitoring (above) -- 44 cables sections of the same cable type.

Again, 10-20 additional cable sections (like above) -- 1x STP.

Electronics:The same as above -- 4x assemblies. (location - close to temp.mon assemblies, in the same rack?).

S.Zelepoukine19.Sep.02

Summary:

1. Revise the front-end electronics solution (reconsider ELMB, R-hard analog MUX, …).

2. Urgently (next week ?) start the first iteration of the DCS cablinglayout outside ECAL; also FE location should be defined -- balconies ?

3. Cabling and sensor probes inside ECAL -- is also an urgent task(to be done ultimately in this year -- November?).

4. Installation procedures -- inside / otside ECAL.When we have to have installed sensor probes/cables?Who will make the installation job?

5. We need to have a list of relevant ECAL milestones (dates!) to see how much we are in short of time.