Evolution of the gas system control for flight WINCAN Macro WINCAN WINCAN Diagnostic WINCAN Basic stop not ok ok WINCAN Monitor Code and Manual available at: http://www.cern.ch/spada/AMS/ F.Spada – AMS TIM April ‘06

ISS <-> ground data communication – software location WINCAN Macro state definitions JMDC HRDL WINCAN Monitor check list ISS GROUND WINCAN Macro State definitions, mixing) log files PC WINCAN Diagnostic WINCAN Basic user interfaces WINCAN Monitor display TRD Status display F.Spada – AMS TIM April ‘06

Security checks Security conditions to be verified before operating on the system On valves: Forbidden to open a valve if the last temperature readout is too old or if temperature is under a fixed threshold Forbidden to open a valve if a heater is on (not enough power) Before opening a valve on the tank - D vessel line, disable the upstream one (avoid two valves open at a time) On heaters No heater on if a Marotta valve is open (not enough power) Keep average dissipation (duty cycle) under a fixed threshold These conditions are automatically taken into account in what follows F.Spada – AMS TIM April ‘06

Defined states of the gas system/1 To minimize the communication with space: define states of the system – the definition resides on the JMDC from ground only send command “bring system in status x” Examples of defined states: state “Ground” Disable all Marotta Heaters off box S Disable all Marotta Close V8 Pumps off HV off Heaters off box C manifold Close all VA, VB, VC, VD F.Spada – AMS TIM April ‘06

Defined states of the gas system/2 state “Empty” bring to “Ground” state box S bring to “Ground” state box C verify temperature open V4 box S ok not ok open V18 box C heaters on bring to “Ground” state box S bring to “Ground” state box C verify pressure in D not ok ok F.Spada – AMS TIM April ‘06 stop

Defined states of the gas system/3 state “Ready” bring to “Ground” state box S bring to “Ground” state box C manifold bring to “Ground” state verify temperature open V8 box C ok open all VA, VB, VC, VD manifold not ok heaters on F.Spada – AMS TIM April ‘06

Defined states of the gas system/4 state “Run” bring to “Ready” state box S bring to “Ready” state box C manifold bring to “Ready” state verify P2 ok not ok stop pumps on box C verify temperature HV on box C ok not ok F.Spada – AMS TIM April ‘06 heaters on

Diagnostic procedures/1 Example of a procedure to determine the status of electromechanical components: check of the Marotta valves in the box S after a dysfunctional behaviour of the pressure in the D vessel. F.Spada – AMS TIM April ‘06

Diagnostic procedures/2 open V1A open V2A open V3A V1A = ok V1B = ? V10A = ? V10B = ? V2A = ok V2B = ? V3A = ok V3B = ? V20A = ? V20B = ? measure P2A ok stop not ok measure P2B ok stop P2A = ko not ok open V10A open V2A open V3A measure P2 V1A = ko V1B = ? V10A = ok V10B = ? V2A = ok V2B = ? V3A = ok V3B = ? V20A = ? V20B = ? ok stop not ok F.Spada – AMS TIM April ‘06

Diagnostic procedures/3 open V20A open V20B open V2B open V3B V1A or V10A = ok V1B = ? V2A or V3A = ko V10B = ? V2B = ok V3B = ok V20A = ok V20B = ok measure P2 ok stop not ok open V1B open V2B open V3B (V1A & V10A) or V20A or V20B = ko V1B = ok V10B = ? V2A = ? V2B = ok V3A = ? V3B = ok measure P2 ok stop not ok F.Spada – AMS TIM April ‘06

Diagnostic procedures/4 open V10B open V2B open V3B measure P2 (V1A & V10A) or V20A or V20B = ko V1B = ko V10B = ok V2A = ? V2B = ok V3A = ? V3B = ok ok stop not ok open V20A open V20B open V2A open V3A V1A & V10A = ko V20A & V20B = ok V1B or V10B = ok V2A = ok V2B or V3B = ko V3A = ok measure P2 ok stop not ok stop P2a, P2b ko??? F.Spada – AMS TIM April ‘06

Summary WINCAN split in four branches Basic Monitor Macro Diagnostic Security conditions included Defined states of the system To do: Continue with safety study More diagnostic procedures … F.Spada – AMS TIM April ‘06

State “Ground” F.Spada – AMS TIM April ‘06 Box S Manifold disable V1a disable V1b disable V10b disable V2b disable V3b disable V20b disable V4b close VimA close VimB close VimC close VimD i = 1, …,5 (6) m = 1, …,8 heaters off Box C disable V6a disable V18a disable V6b disable V18b close V8a close V8b heaters off CP1 off CP2 off F.Spada – AMS TIM April ‘06 HV off