RICH 1 Upgrade Services

This is a rough guess at the number of services required for RICH 1. DO NOT TAKE FOR GRANTED

RICH 1 Services

Mostly taken from a talk at the infrastructure workshop. but based on a plane of 11 columns, a column of 6 modules, and a module of 2 DB and 4 ECs.


Each DB requires a fibre per GBT, there are two GBTs per FPGA, and 3 FPGAs per board. Each DB is coupled to a harness board which merge fibres into ribbons. Each ribbon will remain as a bundle all the way to the TELL40s, so should only contain data. It is envisioned that a 12 fibre ribbon can cover two digital boards, and hence a single module. Patch panel connectors like one of these, probably.


Each DB requres a transmission and receiver fibre coupled through a GBT to the SCA. It is envisioned that a 12 fibre ribbon will serve multiple boards. The ribbons will go all the way to a SOL40, presumably there are no PCIe40s configured for data, ECS, and TFC. Same patch panel connectors as Data.

Low Voltage

LV shared across a column. 8.5 Amps per DB, so 100 A per column, probably at 2.5/5 V? quick back of envelope calc says conductors ~ 7mm diameter (20 m ~ 1V drop). Need, both positive and ground connections.

High Voltage

1.1kV, mostly common to a module, some split powering in high occupancy regions (a 4 by 4 module region) of the last, and maybe last but one dynode. Maybe some SHV connector like, since it's only 1kV? Arrives at the detector as several 56 conductor cables stores), needs to get to the harness as 1 or 2 or 3 SHVs?. Common ground on a column (or to several modules), so patch panel isn't straight through. Will need a patch panel to cover the plane/several columns rather than per column.


Externally, same as now, two loops (one for the up box, one for down box), but beefed up a bit. Internally a cooling bar, with coolant tubes built in. between the two there has to be some manifold, as daisy chaining is probably a bit too much, but the specifics is all provisional.


Most of the monitoring of the detector will come through the SCA, however there will need to be some thermometery inside the enclosure (4-5 sensors?), probably a thermoswitch per column, but maybe per module, some humidity sensors? Potentially the voltage of each DC/DC converter needs to be measured, so 8 per module, 48 per column.

If we assume 6 thermoswitches and 48 voltages per column, we have 108 wires to take out per column, can we reduce this? Additionally we can assume about 30 for thermometry and misc environmental sensors spread through the whole box.


Probably going to have some fibres to inject a laser, 1 x 12 MPO per box like we currently have?


Should probably have some. 1 spare data, 1 spare ECS 12 MPO per column?


Some very incomplete summary tables for different levels.

Per module

Service Number Type Comment
Data 1 12 fibre MPO Some how shared between the two boards
ECS 4 Individual fibres How will they enter the module?
LV 1 Pair of 3mm plugs? That's how it's connected internally now.
HV 1 (+1/2 if split powered?) + 1 gound SHV? Common ground.
Cooling 1 cooling bar All modules connected to a common heat sink
DSS/DCS 8 + 1 TWP? Do we need measure every voltage? Granularity of the thermoswitches?

Per column

Service Number Type Comment
Data 6 12 fibre MPO One per module
ECS 2 12 fibre MPO Shared between multiple modules
LV 1 Pair of screw terminal again?  
HV 6 ( + 4/8 if split powered) + 3/6? ground SHV? Rather speculative
Cooling 2 quick release? Assume similar to current RICH 1, in and out
DSS/DCS 48 + 6 TWP? Do we need measure every voltage? Granularity of the thermoswitches?

Per plane

Service Number Type Comment
Data 66 12 fibre MPO No spares
ECS 22 12 fibre MPO No spares
LV 11 Pairs of scew terminals? One per column
HV 66 + 16/32 (split powering) + ~20 ground SHV? Ground shared at patch panel, probably. Arrives at patch panel as 56 conductor cables
Cooling 2 cooling loop in and out Assumes some manifold somehere.
DSS/DCS ~600 TWP? Really?

Territorial guess

The cross-secional area of a column is $56\times320\mathrm{mm}^2$, so as a first guess we'll say this is the space for per column services.

First guess, no HV or cooling.


For the HV: Assume split poweing of last and second to last dynode + 2 spare channels = 100 so 10x10 SHV array (internal). The inside is the setting the limits, the 56 conductor cables. SHV connector ~ 15mm + 10 mm finger room -> 260mmx260mm patch panel. Would need t be quite thick though.

Internal cabling

An attempt to produce a summary of all the known services from the patch panel to the digital boards.

Red = Very rough guess. Blue = Provisional.

Service Number Cable Dimensions Bend radius Panel connector DB connector Comments
Data 6 12-fibre bundle 5 mm x 2 mm 40 mm Multi MPO feed-through Some 6-fibre MPO splitter 1 ribbon per PDM, how does it get split across the two DB?
ECS 2 12-fibre bundle 5 mm x 2 mm 40 mm Multi MPO feed-through Some 2-fibre MPO splitter 1 ribbon for 3 PDMs, how does it get split between them and across DBs?
LV 12 Thick insulated copper wire 5 + 2(insulation) mm diameter 40 mm 12 pin socket 12 pin socket with high current pins?   Due to power supply limits two PDMs share a supply, so at least 6 cables need + some splitting between PDMs, if split outside means lower current through panel, and prettier inside.
HV 12,16,20 HV coax 3 mm diameter 20 mm Something like 20 pin HV socket 20 pin HV plug SHV 1,2 or 3 HV per PDM + 1 ground
DCS/DSS 12 Some wire         A thermoswitch per PDM?

A cross-section of the potential cable routing assuming above, in a 56x100mm space, with a 15 mm central support structure.


Topic attachments
I AttachmentSorted descending History Action Size Date Who Comment
PNGpng patch.png r1 manage 18.0 K 2015-02-24 - 19:57 MichaelMcCann  
PNGpng cross-section_with_central_support.png r1 manage 63.9 K 2016-01-28 - 11:40 MichaelMcCann  

This topic: LHCb > WebHome > LHCbRICH > RichUpgrade > Rich1UpgradeMechanics > Rich1UpgradeMechanicsServices
Topic revision: r5 - 2016-01-28 - MichaelMcCann
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