alpha magnetic spectrometer – 02 avionics outline

Alpha Magnetic Spectrometer

Alpha Magnetic Spectrometer – 02Phase II Flight Safety Review

Avionics Overview

May 21, 2007

Timothy J. Urban / ESCG / Barrios Technology

May 21, 2007 Timothy. J. Urban / ESCG 2


Alpha Magnetic Spectrometer – 02Avionics Outline



Alpha Magnetic Spectrometer – 02Avionics Overview

Overview caveats:1. The primary purpose of the payload is its science

objectives.2. The payload is designed to be fault-isolated from

vehicle systems, and to be safe without services.3. The only safety related payload operation is magnet

charging, which is either operationally controlled or prohibited.

4. As such, the payload data systems architecture overview is provided as reference information only.




• J-Crate: Data Acquisition Interface Front-end– Interface:

• JLIF: Low Rate Interface• JHIF: High Rate Interface)

– JMDC: Redundant 4X Main Data Computer

• PDS: Power Distribution System (front-end)• CAB: Cryomagnet Avionics Box

– Cryomagnet Current Source (CCS)– Cryomagnet Self Protection (CSP)– Uninterruptible Power Source (UPS)– Cryomagnet Dump Diodes (CDD)



Alpha Magnetic Spectrometer – 02Avionics Overview (continued)

• Experiment Detector Electronics– xCrate: Detector Electronics– xPD: Detector Power– xHV: Detector High Voltage Source

• Other Electronics:– Thermal– Monitor

• Star Tracker• Global Positioning System• Laser Alignment



Systems Architecture• AMS-02 contains electronics boxes that supply the

necessary services for each detector:– Readout– Monitor– Control electronics– Power distribution

• The box nomenclature is generically xCrate, xPD or xHV– where “x” is a letter designating the detector function– “Crate” refers to the readout/monitor/control electronics box– “PD” refers to the Power Distribution box for that specific detector– xHV bricks provide high voltage for some detectors




Systems Architecture (continued)

Values of “x” are designated as follows:• E ECAL• J Main Data Computers (MDC)

and C&DH interfaces• JT Trigger and central data acquisition• M Monitoring • R RICH • S Time of Flight (TOF) Counters

& Anti-Coincidence Counters (ACC)• T Tracker• TT Tracker Thermal• U Transition Radiation Detector (TRD)• UG TRD Gas




Alpha Magnetic Spectrometer – 02Typical Crate Installation



Alpha Magnetic Spectrometer – 02Avionics Layout



Alpha Magnetic Spectrometer – 02Avionics Layout (continued)




COMMAND AND DATA HANDLING SYSTEM



Alpha Magnetic Spectrometer – 02Command and Data Handling System

• J-Crate is the primary Command and Data Handling avionics for the payload– Four redundant Main Data Computers– Processes received commands and provides control to all

subsystems– Transmission point for outbound science data

• Command and Data Handling Interfaces:– STS, via ROEU PDA

• 1553: Low speed commands and telemetry• RS-422: High-speed data

– ISS, via UMA• 1553: Commands and telemetry (LRDL)• ISS Fiber-optic Payload Bus: High-speed data (HRDL)

• J-Crate communicates within AMS-02 – AMS-02 Wire: (High performance serial 100Mbps custom wire,

similar to ESA Space Wire) for High Rate communications– Controller Area Network (CAN) Bus: Protocol for Low Rate

communications




Block Diagram

AMSWire

AMSWire



J-Crate Scheme & test setup4* Main Computer + Interfaces

J-Crate

CompactPCI Bus Backplane

AMS Specific Backplane (ASB) Signals and Power

JSBC

Local Bus

SDRAM Flash PROM

PPC 750 CPC 700

PCI Agent

DP

RA

M

Reg

isters

JIM-CAN

PCI Agent

DP

RA

M

Reg

isters

JIM-AMSW&15

53

PCI Agent

DP

RA

M

Reg

isters

JIM-HRDL/422

JBU

FPGA

JHIF

x4JL

IF

JPD US

CM

AMSWx4

CANx2

Front Panel Connectors

HRDLx2

RS422x2

1553x2

Powerx1

CANx2

CDDCCDDCCDDCCDDCx4

EVA PanelROEU Panel



Alpha Magnetic Spectrometer – 02J-Crate Flight Model



Alpha Magnetic Spectrometer – 02J-Crate 1553 Data Interfaces



Alpha Magnetic Spectrometer – 021553 Interface Architecture

• Separate 1553 Interfaces for STS and ISS• STS interface includes two Remote Terminals (RTs),

sub-addresses RT28 and RT4• ISS interface is somewhat unconventional

– From ISS, AMS-02 is electrically only one RT– The AMS-02 ISS 1553 interface logically reacts as four 1553

Protocol Engines, for redundancy• At start-up, all four are in Bus-Monitor mode

• First command to bring up system is not acknowledged (solely used to select which of the four Protocol Engine goes to RT)



Alpha Magnetic Spectrometer – 02Payload High Rate Data Link on ISS

~ 100Mbit/sMax. 2 Mbit/s

Long-termAggregate

POCC Payload Operations Control Center

NASA:APS Automated Payload Switch (1 of 2, each with 20

programmable interconnects, but only 4 outputs to HCOR)HCOR High-rate Communications Outage RecorderHRFM High Rate Frame MultiplexerHRM High Rate Modem



J-Crate – Performs Top Level DAQ, contains four JMDCs, JLIF, and JHIF

• JMDC – Main Data Computer• Combines Housekeeping data and Science data for distribution• Performs minor processing• Combines pieces of event data into complete event• Converts CAN and AMS-02 Wire to 1553, RS422, and Fiber• TRD Gas control and TTCS control.

• JLIF – Low-rate data Interface – Transceivers for 1553

• JHIF – High-rate data Interface – Fiber Interface and Transceivers for RS422 • USCM – Universal Slow Control Module – 8051 based CPU and O/S with

processing software (data gathering and blocking into types)

• CDP – Common Digital Part – Gate Array, DSP, Memory, s/w code to communicate on AMS-02 Wire – performs digitizing, blocking and compression

• CDDC – Command Distributor/Data Concentrator – Reads CDP queue/combines pieces of single events, distributes commands to CDPs

• AMS-02 Wire – Hi-performance serial 100 Mbps custom wire (similar to ESA Space Wire)

• Controller Area Network (CAN) Bus - Protocol for Low Rate communications

Alpha Magnetic Spectrometer – 02Data System Components



Payload Tiered C&DH System




Alpha Magnetic Spectrometer – 02Housekeeping Data Overview(equivalent to NASA H&S Data)



Alpha Magnetic Spectrometer – 02Science Data Architecture

thresholds, etc., by



Alpha Magnetic Spectrometer – 02Data System resources



Alpha Magnetic Spectrometer – 02Power Distribution System

OverviewThe PDS is the primary power interface for the payload:

– STS, via ROEU PDA– ISS SSRMS, via PVGF– ISS CAS, via UMA

• Performs power isolation per SSP-57003• Power exposure at the above interfaces, when the PDS

is powered by another interface, is precluded as follows:– ROEU PDA diode protected– PVGF diode protected – UMA has a covered connector

• Performs universal power conversion and distribution for the payload



Alpha Magnetic Spectrometer – 02Avionics Overview - Power Systems



Alpha Magnetic Spectrometer – 02AMS-02 Resource Requirements

• Power – Average 2.4 kW– Peak 2.8 kW

• Data– Science Data: 2 Mbps (long-term aggregate)– Housekeeping Data: 10 Kbps– Critical Health Data: 10 bps S-Band, under negotiation with ISS




Mission Phased Avionics Systems

Interfaces and Functions



Mission Phased Avionics Interfaces • STS, via ROEU PDA

– Pre-Launch– Ascent– On-Orbit

• ISS SSRMS, via PVGF• ISS CAS, via UMA




Alpha Magnetic Spectrometer – 02Payload Avionics Universal Interface Diagram



STS Pre-Launch Interfaces

Via T0 through ROEU PDA• Power:

– Payload: 120 VDC from MLP KSC GSE Power Supply– SFHe Vent Pump: 110 VAC from MLP Room 10 A Payload

GSE Power Supply

• Data:– 1553: Low-speed commands and telemetry– RS-422: High-speed data– MLP Room 10A Payload GSE computers (QTY 2)– Computers remotely monitored and operated via dedicated

Ethernet




Alpha Magnetic Spectrometer – 02Avionics Systems Interface Diagram – STS Pre-Launch



Alpha Magnetic Spectrometer – 02ROEU PDA and Interface Panel A

Remotely Operated Electrical UmbilicalPayload Disconnect Assembly

Interface Panel A



• Activate/checkout AMS-02 avionics subsystems and maintenance of cryo-systems– Approximately 500 W @ 120 VDC for J-Crate, cryo-valves, and CAB critical functions– Approximately 500 ~ 1000 W @ 110 VAC for SFHe tank vent pump– Maximum 2 kW (peak) for calibration and contingency– Negotiating PLB thermal loads with STS

Magnet charging on Pad Operationally Controlled– Magnet charge initiation requires a series of transmitted commands, none of which are

stored on-board the AMS-02 computer

Alpha Magnetic Spectrometer – 02Avionics Overview – Pre-Launch



SFHe Tank Vent Pump


• Pre-Launch only• T0 110 VAC interface and ground safety being worked with STS

Program and KSC, including EMI



Payload Data Interface Panel 2 Configuration

• Low rate data (1553) is routed through T0 umbilical to MLP GSE computers from Shuttle PDIP2 with the “AMS-02 1553” switch in the “T0” position, and program provided jumper installed on PDIP2 front panel “J4” connector

• High rate data (RS422) is routed through T0 umbilical to MLP GSE computers from Shuttle PDIP2 via payload provided cable installed between PDIP2 front panel “J103” and “J105” connectors.




Alpha Magnetic Spectrometer – 02Avionics Systems Interface Diagram – STS Ascent



Alpha Magnetic Spectrometer – 02Avionics Overview – Ascent

SFHe Tank Nominal Vent Valve Operation• He Vapor pressure in SFHe tank must be maintained at a

pressure to keep LHe temperature superfluid Endurance & Mission Success

• Vent valve to open when PLB pressure is less than the SFHe vapor pressure (< 20 millibars)

• Must occur during Powered Flight– Porous plug, which allows He vapor vent while containing the

liquid within the tank– When the valve is opened, liquid must not be in contact with the

porous plug, which could act as a pump to drain the SFHe liquid from the tank

Not a safety issue, due the low rate of pumping that would occur Endurance & Mission Success

– Porous plug is designed to be parallel to the acceleration vector during ascent. G-forces during powered flight will ensure only vapors are in contact with the plug at vent opening.



SFHe Tank Nominal Vent Valve Operation (continued)• Baroswitch Electronics (BSE) will open the vent valve:

– 28VDC power from SSP2, Circuit Breaker @ 5A– BSE to implement de-rated over-current protection circuit < 5A

• BSE will open the vent valve when triggered:– Barometric switch to trigger the BSE when PLB pressure is less

than the SFHe (15 ~ 20 millibars).– Time-tagged Discrete Output Low (DOL) command via Backup

Flight System (BFS) General Purpose Computer (GPC) to trigger BSE as a backup @ L+TBD minutes.

• In the event of an STS abort, barometric switch will trigger BSE to close the vent valve during descent.– BSE will be compliant with NSTS/ISS 18978B, NS2/81-M082

• Baroswitch is hermetically sealed• Valve motor is brushless• Thermal analysis to ensure BSE is below auto-ignition temperature

Alpha Magnetic Spectrometer – 02Avionics Overview – STS Ascent



Alpha Magnetic Spectrometer – 02Avionics Systems Interface Diagram – STS On-Orbit



• Configure PDIP1 and PDIP2• Unstow and activate Digital Data Recorder System-02• Activate Assembly Power Converter Units

– Powers AMS-02 Payload• Payload Check-out• Payload Deploy

Alpha Magnetic Spectrometer – 02Avionics Overview – STS On-Orbit



Configure PDIP1




Configure PDIP2




Digital Data Recorder System-02 (DDRS-02)


• Operated on Next Generation Laptop System (NGLS) computer• Serves as a back-up recording device for payload data that is

down-linked via the Ku-Band• Single hard disk in the NGLS computer will provide recording

capability for 40 hours worth of check-out data• Back-up hard-disks flown (contingency)



Payload Power-up and Check-out• Cryocoolers and housekeeping data at ~ MET 2 hr 30

minutes• Activate/checkout AMS-02 avionics subsystems and

thermally condition payload• Peak power draw from Orbiter APCU, quantity 2 wired in

parallel, is 2.8 kW– Avionics thermal constraints may be imposed

No magnet charging is possible on STS – APCU power is supplied to prime PDS side “B”, which has no connectivity to the CAB, and thus the magnet

• Power down AMS-02 prior to transfer operations• Disconnect ROEU ODA from PDA prior to deploy AMS-02




Simplified Payload Power-Up Sequence




Alpha Magnetic Spectrometer – 02Avionics Systems Interface Diagram – Hand-Off



Alpha Magnetic Spectrometer – 02PVGF Location



Alpha Magnetic Spectrometer – 02SSRMS Power Block Diagram



Payload Hand-Off• Grapple Power and Video Grapple Fixture (PVGF) with

Space Station RMS (SSRMS) located on MT– External Berthing Cues System (EBCS) utilized to verify final

approach to Attach Site - Video routed through SSRMS– SSRMS supplies power for AMS-02 Heaters via PVGF during

transfer operationssMagnet charging on SSRMS is Operationally Controlled

– SSRMS Nominal power bus is connected to PDS side “B”, which has no connectivity to the CAB

– Magnet charge initiation requires a series of up-linked commands, none of which are stored on-board the computer

– The payload has no communications via the PVGF to receive these commands

Alpha Magnetic Spectrometer – 02Avionics Overview – Hand-Off



Payload Hand-Off (continued)• SSRMS routes Type II RPCM (25 A) power for AMS-02

Heaters during Transfer Ops, maximum 16.7 Amps– Limited by SSRMS payload bus wire thermal load – Currently implementing current protection circuit, not for the

payload, but to protect the SSRMS payload power bus wiresDe-rating of this protection not required per JSC EEE parts– Proposing elimination of this circuit, based upon cumulative current

limit of the piecemeal protection devices implemented for these heater circuits within the PDS

PSRP Technical Expert ConcurrencePending review and approval from ISS EVR and PICB panels




Payload Hand-Off (continued)• SRMS release of AMS-02• Transfer to S3 attach site • Attach AMS-02 to S3 upper inboard site

– Mechanical attachment via PAS– Electrical attachment via UMA

• Deactivate power via PVGF• Ungrapple SSRMS• Attach UMA and activate power• Power up Avionics, perform abbreviated avionics

checkout to verify payload power and communications




Transfer to ISS

AMS

AMS

AMS on ISS

AMS

SRMS

SSRMS

S3 attach site

1 2

3 4




Berthing to ISS – S3 Upper / Inboard




Alpha Magnetic Spectrometer – 02Avionics Systems Interface Diagram – ISS



On-Orbit ISS Operations • Power-up and complete systems check-out• Thermal monitor and condition cryosystems• Power-down all subsystems except those integral to

magnet charging• Begin magnet charging operations• Post-magnet charge systems power-up and check-out

Alpha Magnetic Spectrometer – 02Avionics Overview – ISS



On-Orbit ISS Operations (continued)Experiment Science:

– 3+ years operation with magnet– After SFHe depletion and magnet is no longer functional, the

payload will continue with further physics goals

• Nominal End of Mission:– No STS flights for return of AMS-02 Payload.– Will remain on ISS for duration of ISS mission life, and re-enter

with ISS vehicle




On-Orbit ISS Operations (continued)• Control of AMS-02 is from groundOnly safety related operation is Cryomagnet charge

– Only safety concern when EVA/EVR operations on AMS-02– Requires a series of up-linked commands (not stored on-board)

• Data down-linked via ISS Ku-Band• Proposed to use S-Band to downlink minimal health data• In case of loss of power and/or communications, payload

is safe without services




Simplified Payload Power-Up Sequence




EVA Connector Panel• EVA Connector Panel allows for redundant avionics

interfaces in contingency scenario– Connectors will meet the mating/demating requirements

identified in letter MA2-99-170, and comply with (SSQ 21654)

• Connections are swapped to effect changing AMS-02 A(prime) / B(redundant) channels in the event that prime capability is lost:– Data: Payload Redundancy Only– Power: Payload and ISS Redundancy

• Contingency release of failed UMACryomagnet charge can be performed on UMA powered

PDS A-side (prime) bus only.




Alpha Magnetic Spectrometer – 02EVA Connector Panel Interfaces

Connector

A

B



Alpha Magnetic Spectrometer – 02EVA Connector Panel Location

EVA ConnectorPanel

UMA



EVA Interface Panel and UMA Operations





Power Systems Detailed



Alpha Magnetic Spectrometer – 02Power Systems Detailed

OUTLINE • Power Distribution System• Payload Bonding• Payload Heaters• Other Power Subsystems• Cryomagnet Avionics Box

– Cryomagnet Dump Diodes– Uninterruptible Power Supply




Power Distribution System – Front End

Provides 1MΩ isolation requirement for payload• Wire sizing is designed to meet:

– NSTS 1700.7B, "Safety Policy and Requirements For Payloads Using the Space Transportation System“

– NSTS 1700.7B ISS Addendum, "Safety Policy and Requirements For Payloads Using the International Space Station“

– NASA Technical Memorandum #TM 102179, "Selection of Wires and Circuit Protection Devices for NSTS Orbiter Vehicle Payload Electrical Circuits"




PDS – Front End (continued)• PDS consists of four sections:

– 120 VDC Input – 120 VDC Output– 28 VDC (Internally Isolated) Output– Control and Monitor (Isolated Low Voltage)

• All 120VDC outputs isolation provided by the end subsystem– DC-to-DC or AC converters– Relays

• Isolation for all other outputs is provided internally to the PDS by DC-to-DC converters

• PDS performs EMI filtration• PDS provides essential telemetry to the J-Crate




PDS – Front End (continued)• The PDS has two independent “channels” side A and side B

which have four identical subsections, as described on the previous page

• The only difference between the two channels is that side A is the only side that has power connectivity to the CAB to perform magnet charging



Alpha Magnetic Spectrometer – 02Power Distribution System Location

PDS




Engineering Model (one-half populated)



Alpha Magnetic Spectrometer – 02Power Distribution System Bonding

The PDS bonding is designed per SSP-30240 Space Station Grounding Requirements, Rev. C:

• Minimum isolation of 1MΩ between:– Primary power positive line and chassis– Primary power return line and chassis– Primary power lines and all the secondary PDS power lines (positive

and return lines)



• The PDS box is equipped with a bonding stud• The PDS Bonding Stud shall be connected to the AMS-02 structure by

means of a bond strap• A copper bus bar is located inside the PDS in order to collect the single

point bonding from the Power Boards– The copper bus bar is isolated from the PDS wall

– The copper bus bar shall be connected internally to the PDS bonding stud by means of ring terminals

• The bonding stud will be connected to the AMS-02 support structure in such a manner:– To conduct electrical faults current without creating thermal or electrical

hazard

– To minimize differences in potential between all equipment

• The mechanical box will operate as a shield against the internally generated emissions and the externally generated emissions.

Alpha Magnetic Spectrometer – 02PDS Bonding (continued)



Alpha Magnetic Spectrometer – 02Power Distribution System Bonding



Alpha Magnetic Spectrometer – 02Payload Bonding

• Fault bond path is achieved through UMA to ISS power systems via 8 awg “green wire” (one per bus) – common with AMS-02 structure

• Payload avionics boxes are bonded to radiators, or USS structure where applicable, with redundant bond straps

• Vacuum Case and Radiators are bonded to USS structure with redundant straps

• USS structure joints:– Some are alodine bonded through riveted joints (not fasteners)– Those joints that do not meet Class R bond will use bond straps

• Bond strap points throughout the payload will be alodined• All thermal blankets are bonded per SSP 30245 and

NASA/TP-1999-209263



Alpha Magnetic Spectrometer – 02Payload Bonding

• Payload level Class R bond supplied through Nickel Plating on V-guides on active CAS

• All GFE is bonded to structure per installation drawings:– ROEU PDA– UMA– FRGF– PVGF– EBCS

• All bonds will be verified at integration:– Electronics and USS structural: Class R – Non-USS structural: Class H– Blankets & Plumbing: Class S



Alpha Magnetic Spectrometer – 02Payload Heaters

• Temperature sensors will monitor all critical temperatures and allow for additional computer control of heaters

• Most non-safety critical heaters are controlled by the PDS and also have at least 2 thermostats in series

• PDS internal heaters have 3 thermostats in series• Heaters are sized for minimum Voltage

– PDS internally converted 28 VDC– ISS provide 120 VDC

• Heaters and thermostats strings are redundant and can be operated by either A or B power feed

• All safety critical heater applications use a 2 fault tolerant control, utilizing 3 thermostatically controlling devices with at least 1 of these devices in the power return leg.



Alpha Magnetic Spectrometer – 02Payload Heaters

• This is typical for safety critical heaters.• However, no heaters are required for safety.



Alpha Magnetic Spectrometer – 02Cryomagnet Avionics Box (CAB)

• The CAB consists of the following subsystems:– Cryomagnet Current Source (CCS)– Cryo Controller and Signal Conditioner (CCSC)– Cryomagnet Self Protection (CSP)

• The Cryomagnet Charge/Discharge Circuit consists of:– CCS– Power Switch– Shunt– Cryomagnet Dump Diodes (External to CAB)– Magnet Coils



Alpha Magnetic Spectrometer – 02Cryomagnet Avionics Box Block Diagram



Alpha Magnetic Spectrometer – 02Cryomagnet Avionics Box Location



Alpha Magnetic Spectrometer – 02Cryomagnet Avionics Box Layout



Alpha Magnetic Spectrometer – 02Cryomagnet Current Source (CCS)

• CCS design includes three protection barriers in series to prevent an actual current at the magnet higher than 459A:– Software protection (value between 455.33A and 459) – Field Programmable Gate Array (FPGA) protection (limit is 459A)– Hard-wired control electronics protection circuitry (limit 459A)

• Isolation for the 120Vdc line (feed thru from PDS) is performed via DC to DC Converters in the CCS– 120 Vdc input is limited to max. 2200 W for power management

• All input/outputs (power and data) from CAB back toward ISS are protected with High Voltage (8kV) protection to prevent feedback from unprotected quench (analysis shows maximum voltage is 5.5 kV).



• The CCS performs magnet charging electrical function• To charge the magnet, the Semiconductor switch on the

charging circuit is closed, and power is supplied to the transformer input.

• The current is slowly ramped up over a period of approximately 1.5 hours to 459 Amps.

• Current during charge and discharge operations is monitored using a 500A shunt.

• The connection from the CCS to the magnet is made via three pairs of 00 AWG wires.

• Once full operating current is reached, the Persistent Switch is closed– The switch consists of a pair of super-conducting wires – “closed” by

cooling them down to superconducting temperatures.

Alpha Magnetic Spectrometer – 02Cryomagnet Current Source (CCS)



Alpha Magnetic Spectrometer – 02Magnet Charging (continued)

• With the persistent switch closed, 459 A is running through both sides of the circuit (the magnet side and the charger side).– To avoid ripple currents through the persistent switch, the current on

the charger side is slowly reduced to zero.

• Once the current on the charger side is removed, the Semiconductor Switch is opened, and the charging system is disconnected from the magnet circuit.

• Mechanical disconnects on the charging leads for the magnet are used to provide thermal isolation from the outside environment during all operations except charging and discharging.

• Prior to charging or discharging, the mechanical disconnects must be connected and cooled, and then disconnected after the operation is complete.



Mechanical Disconnects and Persistent Switch• Mechanical Disconnects are bi-metallic switch operated from

a pre-cooled pressure operated bellow connection• Persistent switch consists of two super-conducting resistors

in parallel that reach 30 ohms when heated above super-conducting temperatures (heated by low voltage heaters to “open”)

Alpha Magnetic Spectrometer – 02Magnet Charging (continued)



Alpha Magnetic Spectrometer – 02Cryomagnet Charge Cable Routing

VC Port for Cable Interface

Charge Cables (00 AWG)

CAB Connections



Alpha Magnetic Spectrometer – 02Cryomagnet Charge Cable VC Interface

Current Leads Soldered

Current Leads Soldered

00 AWG CableAttach Points(X3 each)

VC Port

VC UpperRing



Alpha Magnetic Spectrometer – 02Cryomagnet Dump Diodes (CDD)

• For magnet power down, the mechanical leads are connected and the persistent switch is opened to allow the current in the magnet to be dumped to a bank of 18 diodes:– Half on Port side– Half on Starboard side– Both Port and Starboard banks in series with each other

• The diodes will be mounted on the two wake-side sill trunnion joints (large thermal mass)

• The cryomagnet current will be dissipated conductively as thermal energy to the structure

• These diodes will be protected by a cover to prevent incidental contact

• Dump time is estimated at 80 minutes



Alpha Magnetic Spectrometer – 02Cryomagnet Dump Diodes (CDD) - Schematic




Cryomagnet Dump Diodes (CDD) Subassembly




Cryomagnet Dump Diodes (CDD) Subassembly

Diode

Q-Pad II washer location

Mounting block 3, rectifier assembly C (new design being machined)

Torlon washer & mounting bolts

Bottom Chotherm pad




CDD QM Assembly Sequence




CDD Typical Installation without Protective Cover

CDD Assembly

Sill Trunnion Block

Discharge Cabling




CDD Typical Installation (QM) with Protective Cover

Completed CDD Assembly

Sill Trunnion Block




CDD Locations and Cable Routing

Discharge CablesRouted to CAB

CDD PortAssembly

Bank-to-BankDischarge Cables

Routed under Beam

CDD StarboardAssembly




CDD Thermal Vacuum Test Set-up




CDD Thermal Vacuum Test Set-up

Power Supplies T/C DAQ Modules

Isolated T/C Converter

Thermal VacuumChamber

Diode Bank on Sill Trunnion Block



Alpha Magnetic Spectrometer – 02Cryomagnet Control and Signal Conditioning

• The Cryomagnet Control and Signal Conditioning (CCSC) provides the interface between the AMS-02 Main Data Computers (MDCs) and the Cryomagnet.

• The CCSC is responsible for: – Reception of commands from the MDCs – Transmission of telemetry to the MDCs– Commanding of the CCS– Control of the Cryomagnet auxiliary functions (i.e. heaters, valves,

etc.)– Monitoring of the CCS, Cryomagnet, and CAB operating parameters

and status

• The CCSC also performs system fault detection and management functions, formatting of telemetry, and data storage for system status.

• The CCSC is required to interface with the Uninterruptible Power Source (UPS).



Alpha Magnetic Spectrometer – 02Cryomagnet Self Protection (CSP)

• The CSP performs an assisted magnet quench in the event that an unassisted quench pre-cursory condition is detected.

• The quench protection electronics issues a command to the Uninterruptible Power Source (UPS) to provide a pulse of 45A to quench heaters located throughout the magnet.

• The pulse, for a duration of 150 ms, is required to raise the entire magnet up to a non-superconducting state.– The magnet current is dissipated as heat energy within the magnet.

• After 8 hours, when either power or communications has be lost, the CSP performs an ramp down to protect the magnet.



Alpha Magnetic Spectrometer – 02Cryomagnet Self Protection (CSP)

• Designed for mission success purposes only, no safety hazard The magnet structure will remain safe even if CSP circuitry does

not function

• CSP circuitry is redundant, and designed to identify a quench prelude condition in any individual coil and quench entire magnet evenly

• Redundant heater chains routed to alternating coils (either chain sufficient to quench magnet)

• Protects magnet by ensuring no magnet conductor deformation due to isolated heating, which could result in degraded performance



Alpha Magnetic Spectrometer – 02CSP Block Diagram



Alpha Magnetic Spectrometer – 02Uninterruptible Power Supply (UPS)

• The UPS will consist of a redundant set of Lithium-Ion batteries

• To ensure mission success during loss of ISS power or communication, the UPS battery will provide control power to payload– Watch-dog timer/control circuit– Quench monitoring– Initiation of quench heater 45A pulse– Nominal ramp-down at the end of the eight hours.

• Are sized for a minimum of 8 hours of operation, plus assisted quench operation / ramp down



Alpha Magnetic Spectrometer – 02Uninterruptible Power Supply (UPS)

• Battery is designed to meet:– NSTS 1700.7B, “Safety Policy and Requirements For Payloads Using

the Space Transportation System”– NSTS 1700.7B ISS Addendum, “Safety Policy and Requirements For

Payloads Using the International Space Station”– JSC 20793, “Manned Space Vehicle Battery Safety Handbook”

• JSC EP3 Battery Safety Form



Alpha Magnetic Spectrometer – 02CAB to UPS Block Diagram



Alpha Magnetic Spectrometer – 02Uninterruptible Power Supply Components



Alpha Magnetic Spectrometer – 02UPS Battery



Alpha Magnetic Spectrometer – 02UPS Battery “Bricks”



Alpha Magnetic Spectrometer – 02UPS Battery Management System (BMS)

• BMS is a radiation tolerant circuit that monitors and maintains a series string of eight Li-ion battery cells, with a nominal output voltage of 32VDC.

• The battery is monitored for unhealthy temperature and/or electrical conditions, upon which the system reacts to protect the cells.– Automatic Cell Balancing– Thermal Monitoring– Over-discharge Monitoring– Short Circuit Protection– Cell Over-voltage Monitoring

• BMS consists of three PCBs:– Master Control Board– QTY 2 Monitor/Equalizer boards



Alpha Magnetic Spectrometer – 02UPS BMS Electronics



Alpha Magnetic Spectrometer – 02Other Power Components

• Cryocooler Electronics Box (CCEB):– 120VDC Bus Isolation provided by relays– Over current protection provided by dedicated circuitry in all 8 power

amplifiers– Circuit protection provided by Solid State Power Controller (SSPC) in

PDB and fuse (TBR) in CCEB

• Detector Power Distribution (X-PD) and Detector High Voltage (X-HV):– X: sub-detectors, as previously explained– Galvanic isolation via converters– X-HV are potted for high voltage protection, and cabling has been

sized as well• Maximum 2500 V




Payload and Integration Cables



Alpha Magnetic Spectrometer – 02Payload and Integration Cables

• Since the PDS and J-Crate provide isolation for any faults subsequent to them in the system, payload cables failures are not a threat to vehicle systems

• Integration cables between these components and the ISS and STS interfaces meet the requirements to protect vehicle systems– Proper wire sizing– Designed and manufactured in compliance with SSP 57003– Manufactured and tested by JSC per NASA/JSC-7003



Alpha Magnetic Spectrometer – 02Payload and Integration Cables

• Wire sizing is designed to meet:– NSTS 1700.7B, "Safety Policy and Requirements For Payloads

Using the Space Transportation System“– NSTS 1700.7B ISS Addendum, "Safety Policy and

Requirements For Payloads Using the International Space Station“

– NASA Technical Memorandum #TM 102179, "Selection of Wires and Circuit Protection Devices for NSTS Orbiter Vehicle Payload Electrical Circuits"



Alpha Magnetic Spectrometer – 02Payload Avionics Universal Interface Diagram



Alpha Magnetic Spectrometer – 02Payload and Integration CablesTracking Matrix – reference only




Integrated Payload Avionics Testing



Alpha Magnetic Spectrometer – 02Integrated Payload Avionics Testing

• Integrated Payload testing:– Functional– Beam– TVT– EMI: SSP30237 testing agreed to by EMEP– KSC Post-delivery functional– STS and ISS FIT / IVT

• DDRS-02 Testing– JSC certification– IVT with NGLS– P/L End-to-end Software verification– EMI (delta certification to NGLS – either test or analysis)




COMPLETED

• Suitcase Test Environment for Payloads Testing (May ‘03)

• Preliminary Integration Test (June ‘03)– Taxiscope testing (High Rate Data Link check-out)– 1553 RT Validation testing– APS testing– Orbiter Interface Unit (OIU) Lab Testing

• Functional Integration Test at KSC (January ‘05)– Follow-on at ISS System Integration Lab (ISIL) JSC (June ’05)




PLANNED

• Suitcase Test Environment for Payloads Testing (June ‘07)– PLMDM file transfer protocol

• Electrical Power Quality Test (JSC EPSL) Early FY2008• Testing at KSC (during on-line processing)

– Cargo Integration Test Equipment (CITE)– Payload Rack Checkout Unit (PRCU) / STEP– Early STS IVT with QM J-Crate “OPF Sill-side”– Integrated Payload Orbiter End to End Test

alpha magnetic spectrometer – 02 avionics outline

Documents

data handling avionics

avionics overviewcommand

avionics overviewjcrate

avionics overview jcrate

data handling interfaces

main data computerpds

highspeed data hrdljcrate

data acquisition interface