This simulator traces the full electrical dependency chain from the utility service entrance to the server rack: utility switchgear, an automatic transfer switch, a standby generator, an online double-conversion UPS with battery strings, floor distribution and rack power supplies. Remove the utility, the generator, or both, and watch how stored energy and load service respond.
• Facility laboratory tab: a real-time 3D workbench of the full chain — utility service and main switchgear, the generator transfer switch, the engine-driven standby generator, online UPS power modules, UPS battery strings, the floor power distribution panel and rack-mounted servers with dual power supplies — with Home view, Focus selected part, Show full enclosure/exploded view toggle, Auto rotate, Expand and a clickable component list with callouts; live stats (IT load served, unserved load, battery SOC, battery DC output, conversion loss, net battery energy out); an operating-sequence readout; and experiment controls — Pause/advance simulation (10 ms or 1 s steps), playback speed, IT load slider, utility-available and generator-available checkboxes, and battery energy (kWh) and initial SOC (new trial) sliders, plus action buttons (enable facility, stop experiment, lose utility, restore utility). • Curves & measurements tab: a served/unserved load chart and a battery DC output/state-of-charge history chart, the underlying model equations (Pdc,battery = PIT/0.94; dSOC/dt = −Pdc/(3600·Ecapacity); load requires both an available energy source and an available output path) and snapshot measurements. • Experiments tab: guided scenarios (tracing normal supply through utility/ATS/UPS/distribution, separating from utility so the UPS battery bridges the generator-startup interval, losing both utility and standby generation to watch stored energy deplete under load, and comparing 40 kW versus 100 kW demand with no upstream source), a model verification bench (Run model checks) against independent fresh models, and a timestamped event log with a trial-report export. • Learn & assess tab: lessons on the normal power path, how stored energy bridges an outage, generator recovery timing, and tracing the weakest dependency, a knowledge-check quiz with reset, and a scope/references note.
Under normal conditions, power flows: utility service entrance → automatic transfer switch (ATS) → UPS (rectifier, DC link, inverter) → floor distribution → rack power supplies → IT load. This model represents an online, double-conversion UPS, meaning the inverter is always in the output path — even during a utility loss, the DC link (and therefore the inverter output) keeps running, now sourced from the battery instead of the rectified utility.
When utility is lost, the battery discharges to sustain the DC link while the ATS transfers to standby generation; the generator itself is not instantaneous — it needs start delay, cranking time and a stabilization period before it can be accepted as a source, which is exactly the interval the battery must bridge. If both utility and generator are unavailable, the battery keeps discharging until its modeled reserve is exhausted, at which point load becomes unserved. The model also demonstrates that a healthy source cannot rescue a failed downstream dependency: an available battery cannot feed the load through a failed inverter, since the inverter is a required series link in this fixture (barring a deliberately selected bypass path).
The served/unserved load chart shows how demand is met (or not) as sources change — watch unserved load stay at zero as long as either utility, generator or sufficient battery energy is present, then step up once the battery's reserve is exhausted during an extended dual-source outage. The battery SOC trace declines at a rate set by Pdc,battery = PIT/0.94 (the 94% battery-conversion efficiency) divided by capacity — so doubling the IT load while running on battery alone roughly doubles the rate of SOC decline, which the higher-demand experiment demonstrates directly.
The Run model checks bench validates these energy-balance and availability-dependency relationships against independent fresh model instances, leaving your live trial untouched. This is a logical source-availability and averaged-energy-balance model: it uses 96% mains-conversion and 94% battery-conversion efficiency, a 5% battery reserve floor and a 95% charge ceiling, with open-transition transfer. It does not solve AC waveform behavior, short-circuit current, source synchronization, a specific manufacturer's protection curve, or an automatic static-bypass algorithm.
Utility service entrance and main switchgear feed an automatic transfer switch, which under normal conditions selects utility power for an online double-conversion UPS (rectifier, DC link, inverter). The UPS output feeds floor power distribution, which in turn feeds rack-mounted servers through dual power supplies.
Yes — this model represents an online, double-conversion UPS, so the inverter is continuously in the output path. During a utility loss, the DC link is sourced from the battery instead of the rectified utility, but the inverter itself keeps operating without an output interruption.
The UPS battery continues discharging to support the load, with its state of charge declining according to the load and the 94% battery-conversion efficiency. Once the battery reserve (modeled with a 5% floor) is exhausted, load becomes unserved — the simulator lets you watch this happen at different load levels.
It is a logical source-availability and averaged-energy-balance model using fixed conversion efficiencies (96% mains, 94% battery) and open-transition transfer. It does not model AC waveform behavior, short-circuit current, source synchronization, a specific manufacturer protection curve, or an automatic static-bypass algorithm.