Redundant Power for the Segment Master
A segment master that loses power loses a whole deck. The redundancy story has to start at the supply rail, not at the network port.
Network-level redundancy gets the marketing slide; power-level redundancy is what actually keeps the segment master online. A 24 VDC rail dropping out on a single ship bus is a more common failure than a network cut, and it takes a whole deck offline if the segment master is single-fed.
The architecture
- Dual 24 VDC inputs from independent ship buses with ORing diodes.
- A small supercapacitor bank for ride-through during ATS transients.
- Inrush limiting sized for the worst-case cold start across both inputs.
- Per-input current monitoring telemetry on the same bus as the sensor data.
What we measured in trials
Questions, answered
Why focus on power redundancy rather than network redundancy for the segment master?+
Because a 24 VDC rail dropping out on a single ship bus is a more common failure than a network cut, and it takes a whole deck offline if the segment master is single-fed. Network redundancy makes a good demo; power redundancy is what keeps the demo true in service.
How is the segment master's power made redundant?+
Dual 24 VDC inputs from independent ship buses combined with ORing diodes, a small supercapacitor bank for ride-through during automatic-transfer-switch transients, inrush limiting sized for worst-case cold start across both inputs, and per-input current-monitoring telemetry carried on the same bus as the sensor data.
What did the power architecture achieve in trials?+
Against a typical ~25 ms ship-bus transient during an ATS event, the supercapacitor provided about 800 ms of ride-through at full sensor load — and there were zero detected deck-master outages across 18 months of pilot operation.
Continue the thread
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