Source Transfer Switches
Static Transfer Switch for Source Failover
A static transfer switch for source failover is an 8 kg, thyristor-based switching assembly housed in 316L stainless steel that executes seamless power routing between lunar reactor, solar, and battery sources. Rated for 400 V and 200 A, the device draws 5 W and uses radiation-hardened gate drivers to achieve autonomous, make-before-break transitions in 4 ms. This rapid switching prevents momentary disruptions to critical settlement loads during multi-year missions without magnetospheric radiation shielding, delivering a 25-year operating life and a mean time between failures of 300,000 hours without requiring manual intervention or synchronization across DC supply paths.
Static transfer switches (thyristor-based) providing seamless source failover between reactor, solar, and battery sources without interruption to critical loads.
Purpose
Static transfer switches (thyristor-based) providing seamless source failover between reactor, solar, and battery sources without interruption to critical loads.
Context
Child of L2-PDM-SWGR within the Lunar Ark system
Principles
- ▸Thyristor-based switching enables <0.25 cycle transfer
- ▸Make-before-break operation prevents momentary loss
- ▸Synchronization not needed for DC application
- ▸Coordination with L3-ESS-MGMT-DISP dispatch
- ▸Manual override for maintenance
Typical implementations
- ▸Industrial STS for data centers (terrestrial)
- ▸Submarine source transfer switching
- ▸Spacecraft solar/battery transition heritage
Lunar considerations
- ▸Long-mission source transitions handled autonomously
- ▸Make-before-break protects critical loads
- ▸Periodic test of failover paths
Specifications
Functional
| primary function | Static transfer switches (thyristor-based) providing seamless source failover between reactor, solar, and battery sources without interruption to critical loads. |
| transfer time ms | 4 |
| voltage v | 400 |
| current a | 200 |
Physical
| mass kg | 8 |
| materials | Thyristor stacks, Rad-hard gate driver, 316L SS housing |
| vacuum compatibility | True |
Operational
| power consumption w | 5 |
| thermal range c | -40, 70 |
| lifetime years | 25 |
| mtbf hours | 300000 |
Interfaces
Provides
- Continuously available essential bus
Requires
- Multiple source inputs
- Battery backup
Cite this entry
Lunar Ark Codex. "Source Transfer Switches" (L3-PDM-SWGR-XFER). Retrieved 10 September 2026, from https://lunarark.com/entry/L3-PDM-SWGR-XFER
Licensed CC-BY-SA 4.0. You may reuse and adapt this entry with attribution, under the same licence.