Electrical Feedthroughs
Hermetic Glass-to-Metal Seal Electrical Penetrations
Hermetic electrical feedthroughs are penetration assemblies, typically fabricated from glass-to-metal seals or alumina ceramics, that route power and signal lines through habitat pressure boundaries. To preserve pressure boundary integrity, these feedthroughs must maintain a helium leak rate below 1e-9 atm·cc/sec while ensuring electrical isolation across wide temperature extremes. The lunar thermal environment makes seal longevity difficult, as thermal cycling can crack rigid glass-to-metal interfaces over thousands of cycles. While multi-pin headers reduce the total count of hull penetrations, they concentrate potential leak locations, leading designs toward robust Kovar-glass assemblies or field-repairable stainless steel compression seal fittings.
Hermetic electrical feedthroughs passing power and signal wires through pressure boundaries
Purpose
Hermetic electrical feedthroughs passing power and signal wires through pressure boundaries
Context
Child of L2-STR-PEN
Principles
- ▸Glass-to-metal seals provide hermetic electrical penetration with excellent leak integrity
- ▸Multi-pin headers reduce number of penetrations while increasing conductor count
- ▸Compression seal fittings provide field-repairable alternative to glass seals
- ▸Helium leak rate <1e-9 atm·cc/sec required for pressure boundary integrity
Typical implementations
- ▸Amphenol Hermetic connector series
- ▸Douglas Electrical Components glass-to-metal seals
- ▸Solid Sealing Technology hermetic feedthroughs
Lunar considerations
- ▸Thermal cycling can crack glass-to-metal seals over thousands of cycles
- ▸Electrical isolation must be maintained across wide temperature range
- ▸High pin-count penetrations concentrate potential leak points
Specifications
Functional
| primary function | Hermetic electrical feedthroughs passing power and signal wires through pressure boundaries |
Physical
| materials | Kovar/glass seal assemblies, Alumina ceramic feedthroughs, Stainless steel compression fittings |
Interfaces
Provides
- Hermetic electrical routing through pressure walls
Requires
- Power cables requiring pressure boundary crossing
Cite this entry
Lunar Ark Codex. "Electrical Feedthroughs" (L3-STR-PEN-ELEC). Retrieved 10 September 2026, from https://lunarark.com/entry/L3-STR-PEN-ELEC
Licensed CC-BY-SA 4.0. You may reuse and adapt this entry with attribution, under the same licence.