Redundancy and Failure Simulator — N+1 vs 2N Data Center Power Interactive

Interactive 3D redundancy simulator — switch between parallel N+1 capacity modules and independent A/B paths, fail modules or paths, fail a shared downstream dependency, watch served vs. unserved load and capacity margin, and run a built-in model verification bench.

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About the Redundancy and Failure Simulator

This simulator compares two data center redundancy architectures — parallel N+1 capacity modules and independent A/B power paths — and lets you fail individual modules, an entire path, or a shared downstream dependency to see exactly when a redundancy label stops protecting the load.

What the simulator shows

• 01 Facility laboratory tab: a real-time 3D workbench showing up to six capacity modules, a common output bus and the protected IT load, with Home view, Focus selected part, Show full enclosure, Exploded view, Auto rotate, Expand and Hide/show labels camera controls, clickable numbered components with callouts, live stats, a sequence readout, switch-state tokens and a readings table. Experiment controls include Pause/resume, Advance 10 ms, Advance 1 s, a playback-speed selector (10× slow motion, real time, 10× faster, 1 minute per second), Enable facility / Stop experiment / Open path A / Open path B / Fail shared dependency / Restore dependencies / Reset protection actions, an IT load slider (10–240 kW), an architecture selector (parallel modules N+1 capacity vs. A/B independent paths), installed parallel modules (2–6), module capacity (20–100 kW), failed parallel modules (0–6), A/B path capacity (40–200 kW), and Path A healthy / Path B healthy / Shared downstream failure checkboxes. • 02 Curves & measurements tab: a torque/load operating-point chart, a speed-and-current history chart, the model equations (required module count, remaining capacity after failures, and unserved-load formula), and snapshot readouts for load served, unserved load, capacity margin, parallel/A power, B power and load demand. • 03 Experiments tab: guided presets (one module failed, two failed, A/B takeover, shared bottleneck) plus a Model verification bench ("Run model checks") using independent fresh models, and a timestamped event log with trial-report export. • 04 Learn & assess tab: lessons on determining N, how a module failure removes capacity, why 2N needs complete independent paths, and the distinction between capacity and availability probability, a two-question knowledge-check quiz with reset, and a scope-and-references note.

How N+1 and A/B redundancy differ

In a parallel N+1 architecture, several identical capacity modules feed a common bus: N is the number of modules actually required to carry the design load, and "+1" is one additional module beyond that. If a single module fails, the remaining modules can still carry the full load as long as enough of them survive — three 50 kW modules serving a 100 kW load can lose one module and still meet demand, but losing two leaves only 50 kW, and the shortfall shows up directly as unserved load.

An A/B architecture instead relies on two fully independent paths, each sized to carry the entire load on its own. Opening path A should let path B pick up the full demand — but only if path B's entire chain, including any downstream equipment it shares with path A, is actually independent. The simulator's "shared downstream failure" control lets you fail a common bus that both paths (or all modules) feed into, showing that extra modules or a second source path cannot bypass a single shared point of failure downstream.

Reading capacity margin and verification results

The stats panel reports load served, unserved load, capacity margin, and the power actually carried by the parallel/A source and by the B source. A positive unserved-load figure means the currently available capacity — after accounting for failed modules, an open path, or a failed shared dependency — is below the requested IT load demand. The model equations panel shows how required module count, remaining capacity after failures, and unserved load are computed directly from your control settings.

The Run model checks button in the Experiments tab exercises the underlying capacity and connectivity logic against independent model instances without touching your current trial. This is a deterministic capacity-and-connectivity model, not a reliability or availability-probability calculator: it evaluates one failure state you configure, and does not infer failure rates, repair times, tier certification, or common-cause probabilities.

Frequently asked questions

What is the difference between N+1 and 2N (A/B) redundancy?

N+1 uses one or more capacity modules beyond the minimum (N) required to carry the load, sharing a common bus — losing one module still leaves enough capacity if N is unaffected. A/B (2N) uses two fully independent paths, each sized to carry the entire load alone, so either path can fail completely without affecting the load, provided nothing downstream is shared.

Why can redundant systems still lose the load?

The "shared downstream failure" control demonstrates this directly: if parallel modules or independent A/B paths all ultimately feed through one common point — a shared bus, breaker, or downstream connection — failing that single point defeats the redundancy regardless of how many modules or paths remain healthy upstream.

Does this simulator calculate my facility's uptime or Tier rating?

No. It is a deterministic capacity-and-connectivity model that evaluates a specific failure scenario you configure — it does not compute failure rates, repair times, statistical availability, or Uptime Institute Tier certification, which require additional reliability data beyond capacity and topology.

What does the model verification bench check?

The Run model checks button in the Experiments tab runs automated checks against independent, freshly created model instances — separate from your live trial — confirming the required-module-count, remaining-capacity and unserved-load calculations behave correctly.

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