THEMIS TIMPURGE- 1 UCB, JUNE 16, 2005 THEMIS INSTRUMENT NITROGEN PURGE

THEMIS TIMPURGE- 2 UCB, JUNE 16, 2005 Purge Design Requirements The purge system was designed to comply with the following standards: NASA-STD-5005Ground Support Equipment Design Criteria EWR 127Eastern and Western Range Safety Policies and Practices PAIPTHEMIS Performance Assurance Implementation Plan (UCB Document) THM-SYS-011THEMIS Configuration Management Plan (UCB Document) THM-SYS-004THEMIS Contamination Control Document (UCB Document) SAI-PLAN- 0647THEMIS Mission System Program Safety Plan (Swales Document)

THEMIS TIMPURGE- 3 UCB, JUNE 16, 2005 THEMIS Purge Overview ESA & SST Instruments Require Nitrogen Purge Nitrogen Purge Required Two of the instruments on the THEMIS probes require high purity (99.999%) nitrogen purging – the SST (Solid State Telescope) and ESA (Electrostatic Analyzer) instruments. The ESA microchannel plates are sensitive to condensable hydrocarbons, particulates, and water vapor. The SST detectors are sensitive mainly to particulates. Low Pressure / Very Low Flow (5 psi / 68sccm (.0024 cfm) per Probe) UCB SSL will supply all hardware Oxygen Sensor, 2-stage Regulator, Gages (Blow-Out-Back Type), Relief Valve (10 psi), Shutoff Valve, Filter/Moisture Separator, Flow meter, Hose Assemblies with Quick Disconnects, Manifolds etc. UCB SSL Responsible for Purge With some assistance in monitoring gas supply and providing gas at non-UCB facilities. Purge up until PCA Integration When impractical to purge, 24 hr off-purge limit. Lumaloy bonnets on instruments when covers are off (up until PCA integration)/ Bag PCA and Backfill With Nitrogen Reference THM-SYS-032 PURGE PLAN REV B for more detail

THEMIS TIMPURGE- 4 UCB, JUNE 16, 2005 Probe Purge

THEMIS TIMPURGE- 5 UCB, JUNE 16, 2005 Purge Hardware

THEMIS TIMPURGE- 6 UCB, JUNE 16, 2005 Purge Outline

THEMIS TIMPURGE- 7 UCB, JUNE 16, 2005 Purge Outline cont.

THEMIS TIMPURGE- 8 UCB, JUNE 16, 2005 PCA Bagging 1.Final Instrument Purge Just Prior to PCA integration 2.Bag PCA After Integration 3.Purge Bag For 24 Hours 4.Remove Purge Line. 5.Transport to Pad 6.Remove Bag Just Prior to Installing Shroud