1. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 P3K Palomar Infrastructure u Balance Adaptations Larger Cass weight load from instrument & electronics u Electrical Service Upgrades Higher electric service requirements at Cass, Computer Room and AO Lab u Cooling of Cass Electronic Racks Removal of ~6 kW of heat from below primary mirror J.Zolkower 1

2. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Cass Mounted System Weights u Current AO Cass System Weights AO Bench3820 lbs AO Rack 1 415 lbs AO Rack 2 345 lbs Cables85 lbs AO System Total 4665 lbs u With Heaviest AO Instrument P1640340 lbs P1640 elec.400 lbs Total w/ Instrument5405 lbs J.Zolkower 2 u P3K AO Cass System Weights P3K Bench3900 lb P3K DM rack 1 525 lb P3K DM rack 2 525 lb P3K Ctrl rack 1 258 lb P3K Ctrl rack 2 348 lb Cables475 lb Glycol system 260 lb AO System Total6291 lb uWith Heaviest AO Instrument P1640 / Cal380 lbs (est) P1640/ Cal elec.450 lbs (est) Total w/ Instrument7120 lbs ~1700 lbs more than current maximum

3. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 u P3K Cass mounted component weights exceed current balance adjustments via moving counterweights u New balance adaptations required: 1. Additional ~700 lbs of lead added to weight boxes on Tube upper ring 2. Implementation of up to three dummy electronic cabinets: 2 cabinets loaded with 475 lbs of weight, the third with ~200-300lbs To be applied with lower weight Cass instrument / electronic configurations u Status: Design concept complete. u Risks: Additional load on tube may effect telescope pointing model. No structural concerns have been identified. J.Zolkower 3 Balance Adaptations

4. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Electrical Service Upgrades Power Requirements u Computer Room Electronics (2 Racks) Total Rated Power :11,870 W Total measured continuous measured: 3500 W Continuous + Intermittent measured:5400 W u Cass Cage mounted Electronics (4 Racks) Total Rated Power: 8900 W Total continuous measured: 6250 W Continuous + Intermittent measured: 7210 W Current AO system measured: 1035 W Highest power AO instrument P1640 ~ 500W P1640 Cal power TBD u Chiller in Coude 220 V / 3 Phase / 42 amp service~ 10,000 W J.Zolkower 4

5. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Required Electrical Upgrades u Computer Room Electronics Add 3x 120V / 30 Amp Receptacles (ready for connection) u Cass Cage Add 3x 120V / 30 Amp Receptacles Add Load Center in Cass Cage Insufficient paired conductors available in exiting wrap-up to provide required power (electromagnetic field cancellation concerns) »A new, auxiliary wrap-up will be used to bring required power to Cass »This auxiliary wrap-up will also be used to & from transport glycol to Cass u AO Lab Add 3x 120V / 30 Amp Receptacles, Contactors (ready for connection) u Coude (Chiller location) Add Breakers, Disc. contactors, and Junction Box J.Zolkower 5 Electrical Service Upgrades

6. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Power Dissipation / Mirror Temperature J.Zolkower 6 Current AO power ~ 1000 W

7. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Maximum Heat Dissipation Requirement Specification released May 5, 2010: 1) For all Cassegrain mounted instruments, the maximum heat dissipation shall not exceed 300W under the primary mirror, and 1 kW into the dome air away from the primary mirror. If this requirement is met, it is assumed that the following requirements will also be met except under extreme circumstances. a The heat dissipated by any Cassegrain mounted instrument shall not increase the temperature of the primary mirror, locally or globally, by more than 0.75ºC relative to the mirror baseline temperature. b The heat dissipated by any Cassegrain mounted instrument shall not induce a temperature gradient in the mirror of more than 0.5ºC measured between any two points on the mirror. I. Evaluation of items 1a. and 1b. to be made by comparing values using a 12 point moving average of data taken at a 5 minute sampling rate. II. The baseline temperature is defined as the average of the primary mirror temperature measured at the north and northeast temperature sensor locations. J.Zolkower 7

8. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Cass Rack Power Allocation J.Zolkower 8 These racks to be cooled ~6100 W

9. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Cooling System Functional Parameters u Basic Functional Requirement Provide system for cooling of Cass mounted electronics in order to minimize the heat dissipated to environment below the primary mirror and dome air. u Operating parameters: Ambient temperature range: -10ºC to +30ºC Target Coolant temperature: 3ºC below ambient Cooling fan air flow:Constant speed Coolant Mix:35% Propylene Glycol Coolant Temperature Range:-13ºC to +27ºC Facility Chilled water temp:5ºC to 10ºC (seasonal range) u Thermal modeling of electronic rack heat exchangers by Thermatron to confirm heat exchanger design within proposed operating parameters and define performance requirement of chiller J.Zolkower 9

10. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Heat Exchanger Thermal Model Results J.Zolkower 10

11. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 J.Zolkower 11 Heat Exchanger Thermal Model Results

12. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 J.Zolkower 12 Heat Exchanger Thermal Model Results

13. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 J.Zolkower 13 Heat Exchanger Thermal Model Results

14. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Chiller Specification u Requirements for Cass Electronics Cooling Total heat load: 6100 W Max. coolant flow rate: 16 GPM »DM Racks: 3x 2 gpm x 2 Racks = 12 gpm »Cass 1 Rack: 2x 2 gpm x 1 Rack = 4 gpm Coldest required supply coolant temp: -13ºC (3º below lowest ambient) Warmest required supply coolant temp: +27ºC (3º below highest ambient) u Chiller Construction / Installation for Cass instrument cooling Water cooled chiller: exhaust chiller heat through facility chilled water 7.5 ton capacity chiller from Opti-temp to be installed in Coude lab »Delivery scheduled for Oct 4, 2010 u Chiller Construction / Installation for AO Lab: Acquired Neslab System III Liquid to Liquid Heat Exchangers (no cost to project) »Ready for installation after clean-up and testing Cooling requirements are less stringent when operating in AO lab, so refrig of process coolant not reqd No need to move chiller from dome floor to AO lab or long plumbing runs J.Zolkower 14

15. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Chiller Selection J.Zolkower 15

16. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Chiller Selection J.Zolkower 16 Optitemp Chiller

17. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Chiller Selection J.Zolkower 17

18. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 DM Rack Cooling System Layout J.Zolkower 18 Cage inside Cage outboard

19. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Electronic Rack Heat Exchanger J.Zolkower 19 Delivery of 10 pcs Week of Sept. 20, 2010

20. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 u Cooling system operating strategy requires constant speed fan control of the each 9-fan tray u Xinetics DM drivers control fan speed by a stepped function based on temperature u We do not have access to the Xinetics software required to control fan speed u An alternate fan speed control system is required to operate the fans according to our cooling system strategy J.Zolkower 20 Cooling Fan Speed Control

21. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Cooling Fan Speed Control J.Zolkower 21 Proposed solution from Degree C Accepts up to nine fans ·Synchronizes rotational speeds of 4-wire fans to eliminate beat noise and vibration · Monitors speed of 3-wire fans · Simultaneously controls up to two types of fans · I2C and RS232 communication interfaces · Field configurable through serial interface · Programmable alarm thresholds & fan curve · Open collector alarm output · One onboard/ two external temperature sensors · Non-volatile memory to store configuration · Power & Alarm LEDs with external connections · Software selectable 3.3/5V logic operation · Isolated Fan and Logic power domains · Single/Dual power input · Inrush current limiter for hot swap · Fan failure detection and prediction Delivery of 10 pcs Week of Oct 18, 2010

22. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Electronic Rack Cooling u Work completed Spec and order Heat Exchangers Spec and order Fan Trays & Speed Controller Packaging of DM racks Design & and pre-sourcing of rack plumbing, hose assy, manifold & attachment hardware u Work Remaining Packaging of Cass 1 control rack Installation of HX, fan trays, plumbing into racks Testing of in-rack cooling system prior to electronic integration u Risks More than 72 fans @ >100 cfm flow; Coolant flow @ 16 gpm »Will instrument be sensitive to vibration from fans or coolant flow? J.Zolkower 22

23. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Cooling System Control Motivation: u The P3K power dissipation in the Cassegrain environment will introduce thermal gradients into the primary mirror. The long time constant of the primary mirror and cell will extend the induced thermal effect to instruments that follow possibly degrading the performance of Non-compensated system. u Containing the thermal waste of the system in closed cabinets requires the heat transport away from the telescope environment. The solution proposed requires the enclosure of the sources of heat to be confined to three cabinets. The heat must be transferred away from this closed environment to prevent damage to the electronic systems. u The P3K system may be operated at times unattended locally and a failure of the cooling system must be detected and acted upon before damage occurs. u In addition, the cooling of the electronics requires a liquid under pressure to be circulated in the proximity of the electronics. Leaks or condensation are possible adding yet another risk to the system that must be detected and acted upon. u The operation of this system may require the precise understanding of the cooling systems performance and the secondary function of this system is to provide a telemetry stream for analysis.

24. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 u System Supervisor Requirements Document: http://www.oir.caltech.edu/twiki_oir/bin/viewfile/Palomar/Palm3000/P3KInfrastructure?rev=1;filename=P3K_Cooling_Super visor_Concept_9-17-10.doc http://www.oir.caltech.edu/twiki_oir/bin/viewfile/Palomar/Palm3000/P3KInfrastructure?rev=1;filename=P3K_Cooling_Super visor_Concept_9-17-10.doc u Campbell Scientific 3000 data logger/controller The Campbell data logger and control system has a versatile set of analog and digital inputs and outputs that are programmed with a simple interface and is in use at 4 location already at Palomar Observatory. u Parameters to be monitored: Ambient air temperature and dew point at cabinet location. Cabinet internal air temperature Cabinet wetness Fan Speed Emergency stop status Sensor Bypass configuration (overrides) Chiller coolant temperature (at chiller) Chiller coolant flow rate (at chiller) Chiller enable state Cabinet skin temperature Cabinet coolant flow rates (TBD) Cooling System Control

25. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Cooling Control System J.Zolkower 25 ComponentLocationInterfaceFunction System ControllerCass Cage & AO Lab Chiller, fan control, power contactors Overall system control Ambient air temperature and dew point sensor Near System Controller & Cabinets System ControllerProvide telemetry for coolant temperature set point Internal cabinet air temperature sensor Inside each electronic cabinet System ControllerProvide telemetry of overall system performance and detect over-temperature condition Fan Speed controlEach fan traySystem ControllerSpeed control of fans to pre-set value based on operational mode. ChillerCoude Lab, AO lab System ControllerProvide coolant to heat exchangers at defined temperature offset wrt to ambient temperature Wetness sensorInside each electronic cabinet System ControllerDetect coolant leak or condensation inside electronic cabinet Emergency stopData room, Cass Cage, Coude, AO Lab Power contactors and System Controller Provide means to disconnect power from electronic cabinets and chiller in the event of system malfunction Sensor bypassSystem Controller Provide temporary override of sensor signal so that system can be operated in non- standard modes. Power ContactorAt Chiller, Cass Cage, AO Lab Power dist. center System Controller, Chiller Power Supply, Cass Cage Power Supply Provide disconnection of power from electronic cabinets and chiller in the event of system malfunction. Maybe possible to integrate with PDUs. Functional Definition

26. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Modes of operation: u Constant temperature set point (AO Lab operational mode) Controller maintains a constant internal air temperature u Ambient Temperature Tracking (Telescope operating mode) Controller maintains a temperature relative to the ambient temperature u Dew point avoidance (Telescope operating mode) Controller maintains a temperature relative to dew point for improved safety during high dew point conditions. Cooling System Control

27. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 u Work completed Hardware spec & ordered Initial design complete Initial software design complete u Work Remaining Bench testing to begin after receipt of hardware (Oct 1) Complete System integration and test Cooling System Control

28. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Block Diagram The Block Diagram is simplified to show the locations of the main components. Items to note: Main Power contactors for Cassegrain electronics and Chiller are controller by hardwire to contactors that do not depend on control electronics Chiller fault and Estop signal to use existing telescope patch panels Cooling System Control

29. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Plumbing/Electric to Cass - Drag Line Option J.Zolkower 29 Risk of adverse effects on pointing and balance. Decision made to pursue a fixed plumbing arrangement; a.k.a. Auxiliary Wrap-up Evaluation of using a drag line to bring coolant and electric to Cass 2x Cooling Lines 1x Electric Cable 2x Cryotiger lines?

30. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Auxiliary Wrap-up Routing J.Zolkower 30 Turning Guide Attached at yoke bottom center South Polar Axis Routing To Coude

31. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 J.Zolkower 31 Auxiliary Wrap-up Routing Dec Axis East ArmTube

32. P3K Infrastructure – July 19, 2010 East Arm Spool Attached To Tube (Tube not shown) Guide trough (cutaway) Attached to East Arm Dec Axis Wrap-up Concept Dec axis Igus Cable Carrier

33. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Cass Plumbing & Electric Routing Cooling distribution manifold Electric Load Center South side Duct for hose routing

34. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Cooling Distribution Manifold J.Zolkower 34 2 Required Cass Cage AO lab B&G Balance Valve Parker Quick Coupling Stainless Steel Manifold

35. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Southwest side Cass Plumbing & Electric Routing Liquid cooled rack locations

36. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Pressure Drop of Coolant Plumbing u Compared flow velocity of main supply/return lines with 1 and 1 ¼ dia plumbing. At 16 gpm 1 6.5 ft/sec; 1 ¼ 4.2 ft/sec u Calculate viscosity of 35% Propylene Glycol / water mix at -13ºC (lowest coolant temp) 5.67 cSt, Using blended viscosity equation u Calculate Reynolds Number: for 1 ¼ Re= 7120 Turbulent flow u Using DArchy-Weibach eq., Calc pressure drop for 100 ft of pipe 1 pipe dP = 10.5 psi / 100ft 1 ¼ pipedP = 3.5 psi / 100ft 30% less than 1 pipe u Repeat process for ½ Cass Cage plumbing J.Zolkower 36

37. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 J.Zolkower 37 Pressure Drop of Coolant Plumbing

38. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 J.Zolkower 38 Pressure Drop of Coolant Plumbing

39. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 J.Zolkower 39 5 HP pump 3 HP pump Telescope & Rack plumbing dP ~ 32 psi @ 16 gpm Chiller internal dP ~ 11 psi @ 16 gpm 2 HP pump Pressure Drop of Coolant Plumbing Optitemp Chiller

40. P3K Infrastructure – July 19, 2010 P3K Infrastructure I&T 9-22-10 Cooling / Electrical System Distribution u Work completed Distribution Manifold design Spec and pre-source of distribution manifolds, controls, valves, and pre- fabricated hose assy u Work Remaining Design of Auxiliary Wrap-up Spec & procurement of Aux Wrap-up components Installation of Chiller in Coude (electric & plumbing) Installation of Neslab at AO Lab Procurement of manifolds, controls, valves, and pre-fab. hose assy Installation of Distribution Manifold in AO Lab and Cass Cage Installation of Auxiliary Wrap-up Complete System integration and test u Risks Aux Wrap-up varying effect on balance. Need to analyze. J.Zolkower 40