1. 1 13 Octobre 2011 Laurent Roy ATCA Crate / Infrastructure in place -Rack in D3: dimension -Electrical power availability -Tell1 racks running in D3 (air ventilation, safety aspect) -Temperatures, power of crates in D3 -Conclusion

2. 2 13 Octobre 2011 Laurent Roy Rack in D3 dimensions: 2m54 x 60 cm x 90 cm - Useful space : height 56U (2m49) ~10U need to be free at the bottom for cabling and water valve access. width 19’’ (48,3cm) depth ~73cm -Level1 crates : 11U (9U+2U Fan) x 19” x ~72cm -ATCA crate (ex: ELMA catalogue)  dimensions OK, few mechanical adaptation (26U instead of 22U used for 2 crates).

3. 3 13 Octobre 2011 Laurent Roy Electrical Power for Frond End racks in D3 Maximum available: ~ 410 kW Consumption total: ~ 70 kW (in ‘Physics’ mode)  No problem with ‘general power’ (17% of the capacity used)

4. 4 13 Octobre 2011 Laurent Roy -Electrical power available per rack distribution designed for 11 kW/rack max. 16 A circuit breakers (Merlin Gerin C60H – D16A). 7 single phase power outlets available (burndy connector). -ATCA crate consumption: ?? ex. ELMA catalogue: Output PSU 2799 watt maxi -> input (80%) ~ 3.5 kW maxi = ~ 16A  16A circuit breaker should be Ok (to be check with the manufacturers)

5. 5 13 October 2011 Laurent Roy -Cooling: vertical air flow mixed water exchanger Air temperature inside the rack with 2 exchangers: ~ 18-19 ˚C - Safety aspect (DSS): Thermo switch: 40 ˚C (increase to 60 ˚C possible), Smoke detection, CO2 automatic triggering.  ATCA Crate need to be adapted (by the company?) to be compatible with vertical air flow. water:16 ˚C

6. 6 13 Octobre 2011 Laurent Roy 24 Tell1+L1 crates location / 8 racks spare in D2 ‘Detector Extension’ row  enough space Air Temperature in Rack (‘Physic mode’):

7. 7 13 Octobre 2011 Laurent Roy Cooling / power dissipated -Tell1 crate Velo: 17 Tell1+2 Hugin power ~820 watts / 865 watts in ‘Physics’ -> total 2 crates = ~ 1.7kW/rack ( Temp inside rack 19˚C ) Other example: TT 16 Tell1 + 1 Hugin ~645 watts / 705 watts in ‘Physics’ -ATCA crate: maxi 14 boards x 250W = ~3.5 kW ->total 2 crates = ~7.0 kW maxi /rack (4 times more !) Tests done in 2002 by PH electronic group (3 exchangers, 3 crates): http://cdsweb.cern.ch/record/38031/files/epess-2003-014.pdf Conclusion: “ The air-water rack cooling system developed for LEP and used for the measurements in this report can cope with a total power dissipation of the order of 10kW with less than 2% power loss to the surroundings. This corresponds to a useful power dissipation per subrack of 2.3kW. In these conditions most of the electronics is below 40 ˚C ”  Cooling in place should be Ok (but 40˚C inside?), maybe a third exchanger need to be installed, need to be check more in detail, tests ? … = total 6.9 kW for 3 crates

8. 8 13 Octobre 2011 Laurent Roy Heat removed by water: Temp input: 16 ˚C Temp output: ~ +0.5 ˚C Flow ~ 60m3/h  ~ 35kW Heat ‘lost’ in room removed by air conditioning units Air temperature in the rooms: ~ 20.5 ˚C ~ few kW (D3A unit capacity: 26kW maximum) (D3B unit capacity: 32 kW maximum) Dissipation in detector side ~ 30kW ? Rack Temp inside: 18-19 ˚C Total Electrical power: (Level1+LV+HV+…) 70 kW General power summary

9. 9 13 Octobre 2011 Laurent Roy Heat removed by water: Temp input: 16 ˚C Temp output: ~ +0.5 ˚C Flow ~ 60m3/h  ~ 35kW (+ 30-70 kW with ACTA) Heat ‘lost’ in room removed by air conditioning units Air temperature in the rooms: ~ 20.5 ˚C ~ few kW (few additional) (D3A unit capacity: 26kW maximum) (D3B unit capacity: 32 kW maximum) Dissipation in detector side ~ 30kW ? Rack Temp inside: 18-19 ˚C Total Electrical power: (Level1+LV+HV+…) 70 kW General power summary Maxi ~ 105kW need to be removed with water = output + 1.5 ˚C (instead of 0.5 ˚C)  Ok with general cooling (ex. + 4˚C for PC farm in ‘Physics mode’) Remove L1 crates ~ -12kW Add ATCA crates ~ +40-80kW ? (depend on boards quantity)  Total ~ 30-70 kW ? additional

10. 10 13 Octobre 2011 Laurent Roy CONCLUSION: -ATCA crate 19 ’’ dimensions compatible with Rack used few mechanical adaptation needed 13U instead of 11U -General electrical distribution already in place enough -Maximum breaker in place 16A (but could be changed if needed) -Crate should be adapted for vertical air cooling -Heating power to be evacuated per rack ~ 4 times more / current L1 rack  need to be check with more detail (boards quantity/crate) installation of additional 2U exchanger ? -General cooling power enough -Rk: cabling arrangement should be also taken into account early

11. 11 13 Octobre 2011 Laurent Roy spare slide