1. M. Diaz-AguadoFIELDS iPDR – Thermal Solar Probe Plus FIELDS Instrument PDR Thermal Subsystem Millan F. Diaz-Aguado SSL Berkeley mdiaz-aguado@ssl.Berkeley.edu 1

2. M. Diaz-AguadoFIELDS iPDR – Thermal Overview FIELDS Antenna Design –V1-V4 –V5 MEP Thermal Design MAG Thermal Design SCM Thermal Design Mission Phases Thermal Requirements –Subsystem temperature requirements –Testing temperature requirements Thermal Environment Thermal Assumptions Analysis Temperatures Heater Power by Phase Peer Review Status - Advisories Future Work 2

3. M. Diaz-AguadoFIELDS iPDR – Thermal Antenna Thermal Design Niobium C103 for whip and shield Sapphire alumina insulators Molybdenum TZM for brackets and antenna stub Radiator on Preamp white paint (Z93) Isolated from the SC (Titanium shim) Preamp Power 0.28 +/- 15% W Preamp Heaters are 2.3 W (@70% duty cycle, 1.6W) Monopod, pin-puller MLI blanketed and isolated from SC Whip-fork isolated from SC Whip/Shield Nb C103 Nb C103 (Moly TZM backup) Preamp Radiator Pin Puller Monopod Pin Puller 3

4. M. Diaz-AguadoFIELDS iPDR – Thermal Whip Antenna Thermal Design MLI Blanket between the assembly and the SC radiator Pin-puller white paint (Z93 C50) –Slew at phase 2 drives the thermal design White paint on stub-cage mount (V3) GeBk (or STAMET) on aluminum structure MLI blanket on flyweight brake Preamp operational temperature is -55 ° C to 55 ° C Preamp survival temperatures is -55 ° C to 70 ° C 4 High Temperature MLI MLI Z93 White Paint

5. M. Diaz-AguadoFIELDS iPDR – Thermal V5 Preamp Antenna Thermal Design Ultem isolators from carbon fiber boom Aluminum antennas –Clear Alodined Antennas thermally isolated from preamp MLI blanket on box Heat load 0.1+/-15% W Preamp operational temperature -175 ° C to 40 ° C Preamp survival temperature -220 ° C to 60 ° C Antennas Isolated from Preamp MLI Blanket 5

6. M. Diaz-AguadoFIELDS iPDR – Thermal MEP Thermal Design Z307 Conductive Black Paint (high emittance surface required for boxes inside the SC) #8 bolts contact box to panel (wet contact) 8.5W/°C (+/- 15%) Max power draw 16.5 W (+/-15%) Operational Temperatures -15°C to 55°C Survival Temperatures -20 ° C to 60 ° C 6

7. M. Diaz-AguadoFIELDS iPDR – Thermal Thermal Environment 7 Orbit LocationHeat Flux Maximum solar flux at solar encounter (9.86 Rs) 651 KW/m 2 Minimum solar flux at aphelion (1.02 AU) 1314 W/m 2 Maximum solar flux during communication slew (0.7 AU) 2790 W/m 2 Venus albedo0.8 ±0.02 Venus IR emission153 W/m 2 Coronal heating at solar encounter (9.86 Rs) < 3 W/m 2

8. M. Diaz-AguadoFIELDS iPDR – Thermal Cases Studied – Mission Phases Deployment 8

9. M. Diaz-AguadoFIELDS iPDR – Thermal Mission Phases that Drive Thermal Design Mission Phase 2 –SC maneuvers to warm their radiators –Antennas are not deployed yet –Pin-pullers get warm Mission Phase 6 –Deployment of antennas –Operation of pin-pullers and hinge parts, including flyweight break Mission Phase 20 –SC closest approach to the Sun –Antennas and shield are exposed to 651 KW/m² –Limit heat input to the SC Mission Phase 113-120 –SC power constraint during operations limits operational heaters 9

10. M. Diaz-AguadoFIELDS iPDR – Thermal Thermal Assumptions V1-V4 Survival Heaters 2.3W heater (70% duty cycle, max 1.6W) MAG Heaters (1.4 W, 30% loss, at 70% max 0.65W) SCM Survival Heaters Aluminum 6061, Titanium Ti-6Al-4V, Niobium C103, Molybdenum TZM MLI e*=.03/.05 Preamp Heat Load (v1-v4) 0.28 W +/-15% Preamp Heat Load (v5) 0.1 W +/- 15% MAG Heat Load 0.06 W +/-15% MEP Heat Load 16.5W +/-15% 10 BOLEOL αεα/εαε Black Nickel0.810.263.120.790.243.29Previous testing (MAVEN) Black Paint Z3070.970.891.090.930.851.09Previous testing (MAVEN) GeBk0.500.810.620.550.780.71 Will be changed to new values given to us by APL of STAMET (similar to GeBk) White Paint Z930.130.940.140.450.880.51Goddard Previous Testing Niobium C1030.460.401.140.620.302.09Testing PROMES (+/-15%) Molybdenum TZM0.330.142.340.330.142.34 Testing PROMES(conservative values as a/e goes down as temperature increases) Aluminum Clear Alodine.13.091.44.23.082.8Previous Testing (MAVEN)

11. M. Diaz-AguadoFIELDS iPDR – Thermal Thermal Requirements 11 Cold Survival (°C) Cold Op. (°C) Hot Op. (°C) Hot Survival (°C) Whip/Shield*-140351305 Preamp V1-V4-55 5570 Hinge-75-7070170 Pin-Pullers Pre-Actuation -55 60 Post-Actuation -120--100 MEP**-20-155560 Preamp V5-220-1804065 *Temperature predicts with α/ε from PROMES testing **Box inside the SC, thermally conductively coupled to surface

12. M. Diaz-AguadoFIELDS iPDR – Thermal Design and Test Temperature Requirements (Instruments Outside SC) 12 +/-10°C* is the analytical & design margin that is to be defined by each instrument *5°C temperature difference is the APL standard for actively temperature controlled instruments **Antenna and Shield are excepted, with a +100 ° C hot margin instead of +10 ° C, EDTRD_0193. This margin is added to the predicted temperatures. Non- operational survival test limit Non- operational survival predict Operational predict Non- operational survival test limit Non- operational survival predict Operational predict Required science operational limits (if applicable) 10°C* (TBR) + 10°C (TBR) + 10°C* (TBR) + 10°C** (TBR) + Operational test, flight allowable

13. M. Diaz-AguadoFIELDS iPDR – Thermal Design and Test Temperature Requirements (Boxes Inside SC) 13 Non- operational survival test limit 5°C Operational Testing & Flight allowable limit 10°C Analytical & design margin Operational prediction Non- operational survival test limit 5°C Operational Testing & Flight allowable limit 10°C Analytical & design margin Operational prediction Maximum expected T-range -30°C-25°C-15°C 55°C 65°C 70°C Temperatures indicated are S/C panel interface temperatures MEP

14. M. Diaz-AguadoFIELDS iPDR – Thermal Heat Flux Thermal Requirement Limit of heat flux from FIELDS to SC 14 SCFIELDSComments SC Bus6 WConductive from monopod to SC Bus and whip fork TSA25 WConductive from antenna base shim to TSA CSPR253 WRadiation from Antenna to CSPR SC

15. M. Diaz-AguadoFIELDS iPDR – Thermal Test Thermal Requirements 15 Cold Survival (°C) Cold Op. (°C) Hot Op. (°C) Hot Survival (°C) Whip/Shield-150251405 Preamp V1-V4*-60 6580 Hinge-140-7045215 Pin-PullersPre-Open-130-805070 Post-Open-130--115 MEP-30-256570 Preamp V5-230-1904075 *Survival and Operational Heater Controlled

16. M. Diaz-AguadoFIELDS iPDR – Thermal Predict Temperatures 16 Cold Survival (°C) Cold Op. (°C) Hot Op. (°C) Hot Survival (°C) Whip/Shield-135.638.71302 Preamp V1-V4*-52.5-52.5*49.465.6 Hinge-127.0-59.030.6208 Pin-PullersPre-Open-118.3-68.635.462.4 Post-Open-77.2--104.8 MEP-30-17.275.670 Preamp V5-216.7-177.54.360.2 * Op. cases cold temperature (phases 106,109). Cold science (Phases 113-121). is -50.3 ° C, heater setpoint is -55 ° C

17. M. Diaz-AguadoFIELDS iPDR – Thermal Heater Power Survival and Operational Heater Power –V1-V4 (set-point -55 ° C) 17 Phase: MP101MP102MP103MP104MP105MP106MP107MP108MP109MP110MP111MP112MP113MP114MP115MP116MP117MP118MP119MP120MP121 Operational:Off OnOff OnOff On Distance from Sun (AU) 1.02 1.010.90 0.820.750.720.700.250.1620.1270.0930.0720.0600.0520.0440.093 Node/UnitsWWWWWWWWWWWWWWWWWWWWW Preamp_V10.160.190.221.400000.340.4700.59000000000 Preamp_V20.3200.960.760.750.5800.750.390.520.920.65000000000 Preamp_V30.171.301.600000.410.5300.61000000000 Preamp_V40.3500.860.720.660.4900.670.410.530.940.62000000000 Worst Case Hot Survival Worst Case Hot Operational Pre-Science Phases

18. M. Diaz-AguadoFIELDS iPDR – Thermal Heat Flux Heat Flux from instrument to SC (W) for Phase 20 –Negative heat flux means from SC to instrument –Requirements: Instrument to TSA 25 W Instrument to CSPR 253 W Instrument to SC Bus 6 W 18

19. M. Diaz-AguadoFIELDS iPDR – Thermal Peer Review Thermal Advisories #Originator Advisory 13GeneralCheck thermal isolator at Hinge Mount interface. 14GeneralThermal treatments are needed for all surfaces. 17Stu HarrisCheck Thermal input to the preamp due to harness. 19Chris SmithCheck deploy cases for Hinge and Release temps. 20Chris SmithCheck thermal shield sizing. 21Chris SmithDetermine coatings for back of shields. #Answer 13The Interface between the TSA and the Hinge is titanium 14All surfaces are treated thermally 17Modeled coax cable, preamp is not affected by the heat leak 19All cases are checked, including deploy cases 20Thermal shield sizing has been checked 21The coatings for back of the Hinge shield is alodined No RFA’s were received, six thermal advisories were received and answered 19

20. M. Diaz-AguadoFIELDS iPDR – Thermal Back Up Slides 20

21. M. Diaz-AguadoFIELDS iPDR – Thermal Future Work 21  Board Analysis  Voltage Regulators  Basic rule of thumb: 2oz. Copper layer per Watt board Junction Case R pin R bond Q case Θ jc Junction Temperature, Tjunction = Tboard + Q*Rtotal Total Resistance, Rtotal = Θ jc + 1/(1/R bond + 1/R pin ) PartQTYTotal Peak Power (W) Total Nominal Power (W) Peak Power Per Part (W) Nominal Power Per Part (W) Junction to Case Thermal Resistance (°C/W) # Of Pins Bonded (CV-2943) Junction/CaseComponent Temperature (°C) at Peak Power Component Temperature (°C) at Nom Power OP40010.550.360.550.361014NoJunction5551 RNC65, RES (300)10.40.3250.40.325 2YesCase46 OP20010.30.2050.30.205168NoJunction5451

22. M. Diaz-AguadoFIELDS iPDR – Thermal EDTRD Thermal Requirements 22 EDTRD #Requirement Description EDTRD_0182Instruments mounted internally to the SC bus shall meet the thermal design requirements EDTRD_0183, (same as 0057) Instruments shall be isolated from SC shall provide at least 40 °C/W EDTRD_0185Instruments brackets shall be blanketed EDTRD_0186Instruments shall be designed and tested to the thermal interfaces listed in Table 5-2 (-25°C to 65°C Operational, -30°C to 70°C Survival) EDTRD_0187Cold turn on and warm-up sequence shall be identified and defined for each instrument (TBR) EDTRD_0188Instruments shall be designed to operate within specifications for the science phase of the mission and not suffer permanent degradation during any other phase of the mission

23. M. Diaz-AguadoFIELDS iPDR – Thermal EDTRD Thermal Requirements 23 EDTRD #Requirement Description EDTRD_0056Component designs that are thermally coupled to the spacecraft shall have TBD between the component baseplate and spacecraft mounting surface where needed for the thermal load EDTRD_0057Instruments shall be isolated from SC shall provide at least 40 °C/W EDTRD_0058Components that are located internal to the spacecraft bus shall have a surface emissivity of 0.85 or greater EDTRD_0065All spacecraft components shall be designed to operate within specifications for all phases of the mission EDTRD_0189Instruments shall complete a successful thermal vacuum flight qualification testing program prior to delivery to the SC

24. M. Diaz-AguadoFIELDS iPDR – Thermal EDTRD Thermal Requirements 24 EDTRD #Requirement Description EDTRD_0190Testing program shall consist of thermal vacuum balance and thermal vacuum cycle EDTRD_0191All instruments thermal test plans shall be provided to the SC thermal engineer for review and approval EDTRD_0192Flight predictions shall demonstrate at least 10°C of margin within the instrument operational or survival test temperatures with the exception for active heater control (5°C is acceptable) EDTRD_0193 Flight predictions for atypical instruments, SWEAP-SPC and FIELDS PWI, shall demonstrate at least a 10°C margin on the cold side and at least 100°C margin on the hot side for minimum and maximum temperatures EDTRD_0194Instrument level thermal vacuum balance test shall be performed for thermally isolated instruments EDTRD_0195The thermal hardware for these instruments forgoing the thermal balance test shall demonstrate in thermal cycling that all thermal hardware works as expected

25. M. Diaz-AguadoFIELDS iPDR – Thermal EDTRD Thermal Requirements 25 EDTRD #Requirement Description EDTRD_0196The test shall simulate SC conductive and radiative interface temperatures, space radiation couplings, and environmental heat inputs EDTRD_0197Thermal balance spacecraft simulated temperatures are in Table 5 ‑ 2. Instrument component limits defined in the instrument test specification shall have a 10°C margin for testing, as illustrated in slides 4-5 (-25°C to 65°C Operational, -30°C to 70°C Survival) EDTRD_0198The instrument thermal control system shall demonstrate the ability to maintain temperatures within survival limits while in non-operating mode and within operational limits while in operating mode EDTRD_0199Instruments shall demonstrate via testing proper function of survival and operational heaters EDTRD_0200The test shall measure the isolation scheme resistance, which includes the bracket, bolts, grounding straps, and harness cables, between the instrument and the SC

26. M. Diaz-AguadoFIELDS iPDR – Thermal EDTRD Thermal Requirements 26 EDTRD #Requirement Description EDTRD_0201The test shall collect sufficient data to correlate the instrument thermal model to allow untested conditions to be analyzed. EDTRD_0203The instrument thermal model shall be correlated to the balance test at both the maximum hot and minimum cold cases EDTRD_0204Instrument thermal model correlation results shall be within 3°C of the thermal balance test data EDTRD_0205Instruments shall provide a thermal balance test report with correlated model data to the SPP Thermal Engineer EDTRD_0206Cold case balance dwell condition shall be long enough to verify the duty cycle of the survival and operational heaters EDTRD_0207This should decrease transition time between cycles, thus total test time. Instrument component temperatures shall be based on flight model predictions if the isolation coupling is not flight- like

27. M. Diaz-AguadoFIELDS iPDR – Thermal EDTRD Thermal Requirements 27 EDTRD #Requirement Description EDTRD_0208Instrument component temperatures shall be tested to 10°C beyond flight model predictions EDTRD_0209Flight model testing shall complete six operational and one survival cycle EDTRD_0210Engineering Model (EM) testing shall appropriately represent the cycles for each component, and will be approved on a case by case basis by the SPP Thermal Engineer EDTRD_0211The TV test shall include six powered operational cycles and one survival cycle EDTRD_0212CPT’s shall be conducted during instrument level TV testing EDTRD_0213Minimal functional tests shall be performed at all remaining plateaus if no CPT performed

28. M. Diaz-AguadoFIELDS iPDR – Thermal Cold Temperatures Sheet: MP101MP102MP103MP104MP105MP106MP107MP108MP109MP110MP111MP112MP113MP114MP115MP116MP117MP118MP119MP120MP121 Operational Off OnOff OnOff On Distance from Sun (AU) 1.02 1.010.90 0.820.750.720.700.250.1620.1270.0930.0720.0600.0520.0440.093 Node/Units[°C] FIELDS_Whip1 5.1-76.729.2-135.633.942.946.056.290.4104.6103.6105.2388.4546.7652.5815.2957.31077.91182.31299.3809.4 FIELDS_Whip2 3.2101.8-37.3-35.2-37.045.150.458.792.0105.5105.9105.2390.1548.4652.9813.1960.01079.21181.81301.5812.1 FIELDS_Whip3 -26.4107.9-29.2-28.6-28.938.728.252.891.3105.798.9105.0388.4548.6654.9813.7959.31072.31185.11301.6811.9 FIELDS_Whip4 3.4-35.040.0-129.339.748.460.562.591.2105.6110.2105.3388.3549.0654.7814.5957.31076.01180.71298.9811.5 FIELDS_Preamp1 -52.5-52.7-50.3-52.7-44.4-46.8-0.1-38.4-52.6 -26.0-52.6-42.5-37.7-35.3-27.7-21.7-16.3-10.71.6-26.5 FIELDS_Preamp2 -52.6-14.0-52.7 -32.4-52.7 -52.8-52.7-50.3-42.8-39.7-31.0-24.3-19.3-11.72.3-33.2 FIELDS_Preamp3 -52.63.6-52.7 -53.8-52.7 -52.8-52.7-42.9-36.7-34.2-29.5-22.5-16.5-11.50.3-29.3 FIELDS_Preamp4 -52.8-44.7-53.2 -53.1-53.2-18.8-53.2-53.1 -53.2 -49.2-42.0-38.8-32.1-23.8-19.6-12.42.0-31.4 FIELDS_Hinge1 -10.2-34.16.9-125.88.0-7.238.510.7-29.0-20.636.3-25.521.446.060.788.6113.1134.2152.5177.289.4 FIELDS_Hinge2 -10.642.0-64.9-67.6-63.3-49.7-14.0-42.9-30.5-22.6-38.1-27.420.045.261.689.5113.4135.9152.0177.389.3 FIELDS_Hinge3 -13.046.4-61.0-62.1-59.0-53.526.0-46.4-28.4-21.2-43.7-25.820.647.162.191.8112.8134.7152.3176.889.5 FIELDS_Hinge4 -12.7-67.76.0-127.06.97.841.925.3-32.6-24.556.6-29.016.544.261.586.8113.8134.4151.8177.388.3 FIELDS_Shield1 -7.9-105.533.8-129.034.4 62.350.158.172.192.870.8333.4484.9585.0737.0872.2984.61083.71194.5733.5 FIELDS_Shield2 -7.790.4-54.3-52.4-53.3-6.763.35.259.573.642.871.7333.9485.7585.4737.4873.2984.41084.11195.1734.1 FIELDS_Shield3 -8.793.1-48.0-45.8-46.9-28.743.2-18.658.872.610.570.7333.7485.5585.5737.3873.5984.91084.11195.7734.8 FIELDS_Shield4 -8.19.036.1-122.136.542.771.758.158.572.3102.270.7333.1484.7584.5736.3872.0983.41082.21193.8733.4 FIELDS_Pinpuller1 -35.7-101.1-9.6-118.3-4.5-12.948.617.0-50.8-42.434.7-45.6-0.64.67.018.019.220.720.330.514.9 FIELDS_Pinpuller2 -57.925.3-76.7-68.7-66.6-68.4-17.2-66.1-63.4-58.3-77.2-63.5-38.2-28.7-26.6-14.6-13.0-7.0-2.112.3-18.6 FIELDS_Pinpuller3 -60.630.7-68.5-61.3-59.3-61.9-33.3-59.0-61.1-54.6-75.4-58.4-24.5-18.0-14.9-9.0-5.8-1.63.214.8-12.0 FIELDS_Pinpuller4 -36.4-31.5-22.9-111.5-16.6-17.637.110.2-51.9-44.428.3-48.9-13.0-6.4-0.42.111.511.621.232.56.0 MEP -30.0 -17.2-30.0 -17.2-30.0 -17.2 28 Cold temperatures

29. M. Diaz-AguadoFIELDS iPDR – Thermal Hot Temperatures 29 Sheet:MP1MP2MP3MP4MP5MP6MP7MP8MP9MP10MP11MP12MP13MP14MP15MP16MP17MP18MP19MP20MP21 OperationalOff OnOff OnOff On Distance from Sun (AU) 1.02 1.010.90 0.820.750.720.700.250.1620.1270.0930.0720.0600.0520.0440.093 Node/Units[°C] FIELDS_Whip1-100.5-54.353.989.654.581.768.8106.6120.0159.7132.8139.2439.0611.9724.5898.01054.51181.01294.81421.8893.5 FIELDS_Whip286.0132.1-4.632.1-4.685.375.8111.3120.4159.1136.8142.5440.7610.6724.7900.11054.11183.41297.21422.6895.0 FIELDS_Whip392.5141.79.927.410.479.450.7103.6120.5159.7129.6135.3438.7610.5724.5898.41055.61181.31298.11425.4895.6 FIELDS_Whip4-88.4-11.864.192.164.188.086.4114.0120.8159.2140.2145.9439.8611.6725.6897.51053.81183.41293.41422.1892.0 FIELDS_Preamp1-64.8-42.02.940.92.85.765.930.8-3.84.946.648.47.311.915.420.623.328.232.946.320.3 FIELDS_Preamp2-15.221.1-31.5-2.9-31.5-25.66.2-13.8-4.13.4-3.2-3.41.910.112.716.828.530.634.346.621.0 FIELDS_Preamp326.563.2-29.5-19.6-29.5-22.8-9.3-13.1-6.42.4-2.5-1.24.59.212.517.022.829.033.945.618.6 FIELDS_Preamp4-48.8-3.1-19.9-8.1-19.8-16.435.21.7-3.24.113.112.83.010.312.417.825.829.134.046.621.4 FIELDS_Hinge1-105.4-12.430.236.730.124.658.350.93.726.574.477.647.777.695.0121.7149.9166.9186.5212.7121.1 FIELDS_Hinge232.260.3-33.9-20.1-33.6-21.94.7-14.91.122.25.98.146.374.392.2120.5146.6166.6186.1211.6120.8 FIELDS_Hinge334.866.8-30.114.6-30.2-22.442.9-15.63.625.66.08.048.975.695.9121.2145.7167.2186.4213.0124.9 FIELDS_Hinge4-90.3-48.528.231.828.338.862.265.61.422.490.193.246.474.292.0120.1147.3167.2185.1212.0119.0 FIELDS_Shield1-108.4-78.857.780.857.373.688.198.788.8124.9127.8132.2378.8541.7649.2811.1957.11077.01183.61302.6808.4 FIELDS_Shield278.5119.2-20.957.3-20.832.189.551.589.7125.081.886.1379.5542.2649.2811.8957.01077.51183.41302.9808.7 FIELDS_Shield373.2121.7-14.4-11.5-14.510.669.924.789.4125.154.258.0380.0542.0649.2812.0957.71076.81183.81303.5809.1 FIELDS_Shield4-54.432.561.985.361.683.099.0107.689.6124.7136.9141.8379.5541.8649.2810.3956.91076.31182.51302.1808.5 FIELDS_Pinpuller1-58.4-36.732.031.531.834.884.276.318.150.5101.5104.649.251.855.161.963.365.169.679.360.3 FIELDS_Pinpuller212.961.8-11.023.4-11.2-11.031.07.17.927.321.321.922.530.133.739.753.051.156.671.140.6 FIELDS_Pinpuller324.264.5-5.54.1-5.4-3.717.411.48.932.426.628.329.233.436.440.251.051.760.369.041.5 FIELDS_Pinpuller4-57.212.622.111.521.730.372.569.718.446.294.095.142.548.252.060.263.367.374.790.056.1 MEP70.0 75.670.0 75.670.0 75.6 Hot temperatures with heater off

30. M. Diaz-AguadoFIELDS iPDR – Thermal Heaters InstrumentTemperature Set Point (°C)Heater ResistanceControl Type ONOFF FIELDS, FGM 1-25 -20350 Ω (TBR)Elec HW FIELDS, SCM -50 -451041 Ω (TBR)Elec HW FIELDS, PWI 1 -55 -50362 Ω (TBR)Thermostat FIELDS, PWI 2 -55 -50362 Ω (TBR)Thermostat 30 InstrumentTemperature Set Point (°C)Heater ResistanceControl Type ONOFF FIELDS, FGM 2-25 -20 350 Ω (TBR) Elec HW FIELDS, e-sensor (stub) Elec HW FIELDS, PWI 3 -55 -50 362 Ω (TBR) Thermostat FIELDS PWI 4 -55 -50 362 Ω (TBR) Thermostat InstrumentTemperature Set Point (°C)Heater ResistanceControl Type ONOFF FIELDS 1 PWI Mechanisms -65 -60 2535 Ω (TBR) Thermostat FIELDS 2 PWI Mechanisms -65 -60 2535 Ω (TBR) Thermostat FIELDS Survival Heater Set Points, Resistance, and Control Type FIELDS Operational Heater Set Points, Resistance, and Control Type FIELDS Pin-pullers Deployment Heater Set Points, Resistance, and Control Type

31. M. Diaz-AguadoFIELDS iPDR – Thermal SC Thermal Model FIELDS Antennas Deployed 31

32. M. Diaz-AguadoFIELDS iPDR – Thermal MAGS Temps and Heater Power Phase:101102103104105106107108109110111112113114115116117118119120121 Node/Units [W] MAGIB.2 0.7 0.00.70.00.7 0.00.7 MAGOB.2 0.7 0.0 0.7 0.00.7 Phase: Cold101Cold102Cold103Cold104Cold105Cold106Cold107Cold108Cold109Cold110Cold111Cold112Cold113Cold114Cold115Cold116Cold117Cold118Cold119Cold120Cold121 Node/Units[°C] MAGOB.2-33.7-47.734.7-49.234.14.8 -9.9-54.4 29.9-54.5 -54.4 -54.3-54.4 MAGIB.29.121.123.6-52.023.624.0 23.8-50.6-50.718.3-50.8-50.7-50.5-50.6-50.8-50.5-50.7-50.5-50.3 Phase:mp1mp2mp3mp4mp5mp6mp7mp8mp9mp10mp11mp12mp13mp14mp15mp16mp17mp18mp19mp20mp21 Node/Units[°C] MAGOB.2 -13.4-6.619.239.819.41.616.422.6-54.2 42.947.3-54.2 -54.1 -54.0-53.9-54.1 MAGIB.2 -44.4-44.244.664.643.7-6.22.712.6-48.4-48.334.238.4-48.5-48.3-48.4-48.6-48.3-48.5-48.2 Hot Temperatures Cold Temperatures Heater Power (not including inefficiencies), setpoint at -25 º C 32

33. M. Diaz-AguadoFIELDS iPDR – Thermal MAG Model M. Choi (NASA Goddard) model integrated in SC model 33

34. M. Diaz-AguadoFIELDS iPDR – Thermal Preamp V5 Temperatures Phase:MP1MP2MP3MP4MP5MP6MP7MP8MP9MP10MP11MP12MP13MP14MP15MP16MP17MP18MP19MP20MP21 OperationalOff OnOff OnOff On Distance from Sun (AU) 1.02 1.010.90 0.820.750.720.700.250.1620.1270.0930.0720.0600.0520.0440.093 Node/Units [°C] IS_FIELDS_PREAMP. 30-157.3-154.649.060.250.74.38.714.6-169.3-211.133.237.6-169.3-169.2 -169.4-169.2-169.3-169.2-169.1 Hot Cases Phase : MP101MP102MP103MP104MP105MP106MP107MP108MP109MP110MP111MP112MP113MP114MP115MP116MP117MP118MP119MP120MP121 OperationalOff OnOff OnOff On Distance from Sun (AU) 1.02 1.010.90 0.820.750.720.700.250.1620.1270.0930.0720.0600.0520.0440.093 Node/Units[°C] IS_FIELDS_PREAMP. 30-174.4-169.143.2-179.544.0-9.05.7-6.6-177.3-216.729.6-217.0-177.4-177.2-177.3-177.5-177.2-177.4-177.2-176.9 Cold Cases Cold Survival Case Hot Survival Case 34

35. M. Diaz-AguadoFIELDS iPDR – Thermal Thermal Margins Temperature difference (ΔT) between predicts and testing temperatures 35 (°C) Cold Survival Cold Op.Hot Op.Hot Survival Whip Antenna/Shield>10 >100 Preamp V1-V4*5>10 Hinge>10 Pin-PullersPre-Open>10 Post-Open>10 MEP10 Preamp V5>10 *Survival Heater Controlled **Survival and Operational Heater Controlled

36. M. Diaz-AguadoFIELDS iPDR – Thermal SCM Thermal Design MLI Blanket covering the SCM Heat Source 0.325W (+/-15%) Isolated from boom (peek bedplate) Harness wrapped inside MLI 36

37. M. Diaz-AguadoFIELDS iPDR – Thermal MAGs Thermal Design MLI blanket covering the entire MAG Ti-6Al-4V Kinematic mounts with SiN spheres to isolate from boom Shielded twisted pair (STP) 26 AWG wires for heaters (to reduce heat leak) G10 Spacers to isolate mounting plate from boom Power Draw: 0.06W +/-15% (each) Heater Power 1.4 W, 30% loss due to inefficiency 37 Kinematic Mounts with SiN Spheres