1. DCS aspects of TDAQ racks in USA15 and SDX1 Y. Ermoline et al. ATLAS Week, CERN, 15 February 2005

2. 1/7 SDX1 – rack monitoring by DCS (slide from Frascati meeting) nSDX1 TDAQ computing room environment monitored by: n CERN infrastructure services (electricity, C&V, safety) and n ATLAS central DCS (room temperature, etc) nTwo complementary paths to monitor TDAQ rack parameters n by available DCS tools (sensors, ELMB, etc.) n by PC itself (e.g. – lm_sensors) or farm management tools (e.g. – IPMI) nDCS sensors: n 3 air temperature sensors (Pt1000) inside the rack (in front of fans) ðMay be also used as sensors for fan operation monitoring if calibrated n 1 humidity sensor to monitor the dew point inside the rack n one 64-ch ELMB may serve 16 racks, 6-7 ELMB’s in total, 1 CANbus ðsensor wires between sensors and ELMB run up to 30 m ðCANbus branch up to 150 m n extra options (need more ELMB’s and interfaces to ELMB): ðfan rotation and condensed water sensors by CIAT (~400 euros/rack) nSmoke detectors inside the rack to power-off an individual rack n same as Detector Safety System (DSS) smoke detectors

3. 2/7 nWhat can be monitored by DCS inside the racks: n Air temperature ð3 air temperature sensors (NTC 10k), each sensor requires 1 ADC channel and permit measurements from 5°C to >100°C n Relative humidity ð1 humidity sensor (HIH 3610) to monitor the dew point inside the rack, requires 1 ADC channel n Inlet water temperature ð1 temperature sensors (NTC 10k) located on the inlet cooling water pipe, requires 1 ADC channel n Cooler’s fan operation ð3 fan rotation Hall sensors from CIAT (binary and pulse output version available), each sensor requires either 1 bit of digital input port or 1 ADC channel – under discussion nIn total - 8 ADC channels per rack n The ADC channel may be also used to readout a binary signal n 64 ADC channels per ELMB – 1 ELMB per 8 racks TDAQ racks monitoring by DCS (1)

4. 3/7 nWhat is NOT monitored by DCS inside the racks: n Status of the rear door (open/closed) ðNot considered as a really useful n Water leak/condensation inside the cooler ðExpensive (~200 euros/rack from CIAT) n Smoke detection inside the rack ðDoesn’t work with horizontal air flow nWhat is monitored/controlled by other systems: n Status and switching on and off electrical circuit breakers in the rack ðBy TS/EL – under discussion, depends on power distribution implementation n Water temperature in the cooling system ðBy cooling system and general DCS n Smoke detection by CSAM ðCERN safety system TDAQ racks monitoring by DCS (2)

5. 4/7 ATLS DCS tools for sensors readout nThe SCADA system (PVSS II) with OPC client / server nThe PC (Local Control Station) with Kvaser PCIcan-Q (4 ports) nCAN power crate (16 branches of 32 ELMBs) and CANbus cable nThe ELMB, motherboards and sensor adapters ELMB Kvaser Motherboard CAN power crate

6. 5/7 ELMB readout chain (H. Burckhart) 0x3F0x3E0x320x310x30 max. 32 ELMBs CANbus + Power (<100m) LAN Subdetector Control Station PVSS-II + OPC client Local Control Station PVSS-II + OPC Server Kvaser CAN/PCI ELMB Motherboard CAN Power Crate DCS Rack TDAQ Racks sensors Some (yet) missed bits: nThick to thin CANbus cable adapter nELMB daisy-chain adapter for CANbus connector (T-adapter or Y-splitter)

7. 6/7 Possible implementation Sensors location on the rear door Temperature Rotation Humidity All sensor signals and power lines routed to connector to simplify assembly nMinimal configuration - 1 ELMB per 8 racks n 3 ELMBs per USA15, 13 ELMBs per SDX1 ð1 CANbus branch is sufficient in USA15 and SDX1 nMaximal configuration - 1 ELMB per rack n ~20 ELMBs per USA15, ~100 ELMBs per SDX1 ð1 CANbus branch is sufficient for USA15 ð4 CANbus branches is sufficient for SDX1

8. 7/7 Present status and further steps nTest setup is ready for exercises: n PC/NiceXP + Kvaser PCIcan-Q + Cable for PCIcan-Q n ELMB + motherboard + power supply (CANbus + digital/analog) n Kvaser driver + OPC server installed nNote under preparation – first draft discussed with H.Burckhart nSensors and wires choice and adapter design (humidity, rotation) nCAN cable (<100 m for SDX1) choice and CANbus adapters design n Voltage drop in power lines nMechanical arrangement in the rack (ELMB and sensors) nFinal configuration: n One LCS and CAN power crate seems sufficient n Decide on number of CANbus branches and ELMBs