⚙️ Engineering

A rotating coil between magnetic poles, inducing alternating voltage.

Condensing Rankine-cycle steam turbine simulator with a 3D power island, admission/grid controls, temperature-entropy diagram and condenser/cooling loop.

Single-shaft, grid-connected Brayton-cycle gas turbine simulator with compressor/turbine design settings, a pressure-ratio sweep and fault/trip logic.

Gas turbine coupled to an HRSG and steam turbine — see how recovered exhaust heat produces extra, fuel-free electrical output.

Run a wound-field synchronous generator through its prime mover, exciter and breaker, synchronize to a grid or island load, and study phasors, power-angle curves and protection.

Parallel a generator onto a live bus using the synchroscope, three-dark-lamp method and ANSI 25 sync-check permissives before closing the breaker.

Control a static exciter and AVR to regulate a generator's field current, terminal voltage and reactive power on island or grid networks.

Model a turbine governor and watch droop vs. isochronous control restore frequency after a load change.

Follow generator energy through a step-up transformer to the grid, with voltage ratios, losses and thermal behavior.

Balance two generators, renewables and a battery against demand, and see how inertia and dispatch hold frequency steady.

Energize a 50 kVA single-phase transformer, trace core flux and winding heat, and run open-/short-circuit factory tests with fault injection.

Step a balanced three-phase 69 kV supply down to a 13.8 kV bus, comparing vector groups, tap regulation and fault response.

Compare vector groups and neutral connections on a three-phase transformer bank under balanced and unbalanced loading.

Wire wye and delta three-phase connections by hand and see how it changes line and branch voltage, current and power.

Operate an OLTC or DETC tap changer and automatic voltage regulator on a 10 MVA power transformer.

Switch between ONAN, ONAF and OFAF cooling arrangements and trace winding, oil and radiator temperatures.

Charge, close, trip and diagnose a three-pole electronic-trip air breaker, with L/S/I protection tuning and a built-in verification bench.

Open a single-pole contact gap under AC or DC supply and watch current-zero extinction race dielectric recovery against imposed voltage.

Compare an off-load disconnector's visible isolation against a circuit breaker's rated interruption, with interlocks and an absence-of-voltage test.

Adjust primary current, ratio and burden to explore CT saturation, polarity and the open-secondary fault.

Adjust voltage ratio, burden and lead resistance to explore VT phasors, saturation and fuse-failure faults.

Apply feeder faults and follow CT-to-breaker 50/51 overcurrent protection with live time-current curves.

Compare instantaneous (50) and inverse-time (51) relay elements from CT measurement through actual breaker opening.

Use signed terminal currents across a four-terminal bus zone to distinguish internal faults, external faults and CT errors.

Resolve symmetrical AC fault current, decaying DC offset and per-phase current-zero interruption.

Build the power triangle and see what capacitor compensation does to line current.

Inject a ground fault and measure the step-voltage gradient between two feet over a simplified hemispherical soil model.

Inject a ground fault and compare bonded equipment potential against earth-at-feet to explore touch voltage exposure.

Launch a voltage impulse through a nonlinear MOV arrester and see how source impedance and lead inductance affect equipment stress.

Link one-line diagram symbols to physical switchyard equipment and test breaker, disconnect and earthing interlocks.

Compare compensated HV/LV currents against percentage restraint, CT error and harmonic blocking to trip only on internal transformer faults.

Switch between single bus, main-tie-main, ring bus and breaker-and-a-half topologies and see which circuits stay supplied.

Solve a balanced radial 69 kV-to-13.8 kV substation power flow and see how tap, load and feeder impedance drive voltage drop and loss.

Explore ground potential rise, step voltage and touch voltage around a substation grounding system in a simplified soil model.

Wire wye and delta three-phase connections, compare phasors and live meters, and run a break-before-make reconnection demo.

Energize a squirrel-cage induction motor, apply loads and faults, and explore slip, torque-speed curves and a dynamometer mode.

Open a wound lithium-ion cell, follow ion and electron transport paths, and observe terminal voltage, polarization and delivered energy during discharge.

Reconfigure a battery pack between series and parallel arrangements and compare voltage, ampere-hour capacity, current sharing and equivalent resistance.

Compare a battery's true state of charge with a coulomb-counting estimate, introduce sensor bias, and correct it with a rested-voltage calibration.

Trace a regulated CC/CV charger through constant-current, constant-voltage and termination stages, including temperature-inhibit behavior.

Apply an external heater to one of four cells and separate an external heating trigger from a bounded internal reaction and neighbor-to-neighbor propagation.

Trace heat from a cell core through its case, a liquid cold plate, circulating coolant and a finned radiator with fan, out to ambient air.

Inspect cell-voltage taps, Kelvin current sensing, precharge-gated contactor closure and a latched overcurrent/voltage/thermal protection chain.

Compare passive resistor bleed and active energy-transfer balancing on a mismatched series cell string, with SOC spread, loss and delivered-charge readouts.

Run an online double-conversion UPS through utility loss, battery operation, restoration and reserve exhaustion while protecting a critical load.

Dispatch a grid-connected storage rack and bidirectional converter for self-consumption, peak shaving or manual targets, with power/energy limits and SOC reserves.

Explore how light creates electron-hole pairs and drives current in a silicon solar cell.

Trace a 60-cell module's I-V characteristic and see how shading and bypass diodes reshape it.

Start up a 5 kVA grid-following inverter and explore precharge, sync, export and trips.

Compare perturb-and-observe and incremental conductance tracking under shading and noise.

Keep a solar-and-battery microgrid powered through an outage and resynchronize safely.

Explore how wind speed, rotor aerodynamics and drivetrain losses combine to set a turbine's electrical output.

Drive gusts, jam the pitch actuator or reject generator load and watch the governor and collective-pitch mechanism respond.

Discharge, constant-current charge and CC/CV taper a lithium battery pack while watching voltage, SOC and thermal/BMS protection response.

Control real and reactive power through a bidirectional six-switch battery converter bridge within a 100 kVA capability circle.

Dispatch solar, wind and battery storage against demand and utility exchange limits using self-consumption or peak-shaving policies.

Fail the normal source, start and qualify a backup generator, and step through a break-before-make open-transition transfer and retransfer.

Inject a fault at branch, feeder or main bus level and compare time-current curves to see which breakers trip and which loads stay supplied.

Compare automatic occupancy/daylight control, manual-on vacancy control and manual dimming in a two-zone office lighting fixture.

Run a DOL starter and a VFD feeder side by side to compare thermal overload buildup, short-circuit tripping and drive frequency ramping.

Follow current from a panelboard breaker through a branch-circuit conductor to a receptacle or equipment load and back on the grounded return path.

Trace electrical service from the utility transformer through the service entrance, switchboard and panel down to a building load.

Sweep or hold operating points on an induction motor's torque-speed curve with a dynamometer test bench, rotor-resistance effects and a built-in verification bench.

Explore a 3D cutaway squirrel-cage induction motor, run locked-rotor and loaded-start experiments, and study slip, torque and the rotating air-gap field.

Trip a thermal overload relay on a locked rotor, watch thermal memory accumulate and cool, and test reset-block behavior against a teaching trip curve.

Swap phases on an interlocked forward/reverse motor starter and compare a controlled coast-then-reverse sequence against high-slip plugging.

Hold rotor speed with an ideal dynamometer to compare motoring, zero-slip, induction-generating and plugging regimes on the same slip equation.

Ramp voltage and limit current on a thyristor soft starter, watch the bypass contactor engage, and run guided starting experiments with a built-in verification bench.

Sequence K1, KY and KΔ contactors through an open-transition star-delta start and compare reduced starting current against reduced starting torque.

Compare direct-on-line starts, reduced voltage, high inertia and a locked rotor using the evolving fundamental RMS starting-current envelope.

Adjust load and DC field excitation on a synchronized wound-field synchronous motor and observe the torque-angle characteristic through loss of synchronism.

Trace the rectifier, DC link and inverter of a variable-frequency drive as a V/f scalar control law accelerates an induction motor through field weakening.

Trace a start command through PLC ladder logic, contactors and overload relay to a turning shaft, then inject and diagnose real wiring faults.

Fail Path A, Path B, or a shared dependency and watch load sharing, takeover and capacity margin respond.

Adjust containment effectiveness and recirculation and watch server-inlet temperature respond.

Adjust air flow, chilled-water flow and coil capacity and trace leaving-air and inlet temperature.

Step through a utility failure, generator start delay, cranking and stabilization while a UPS battery bridges the gap.

Trace power from utility through the ATS, generator and UPS battery to the rack during an outage.

Load a three-phase rack PDU, shift imbalance onto one phase, and watch branch current, neutral current and thermal trips respond.

Compare N+1 parallel capacity with independent A/B paths and see when a shared dependency defeats redundancy.

Fail source A/B thyristor banks, mismatch phase, and see how transfer timing and load hold-up interact.

Drop utility, fail the rectifier or inverter, and track battery SOC and conversion losses in an online UPS.

Fail the pump or chiller and watch server inlet, coil and water temperatures respond in a closed chilled-water loop.

Compare two fin-and-tube coils, adjust airflow/fouling/frost and read the condenser's heat-balance deficit.

Watch a reciprocating compressor's piston/reed valves and read the ideal P–V indicator cycle.

Balance a variable-speed fan curve against a filter and three damped duct branches.

Compare dry-bulb vs. enthalpy economizer control while mixing outdoor and return air.

Inspect a counterflow induced-draft cooling tower — spray distribution, fill, fan, drift eliminators, basin, makeup and blowdown — and see how fan speed, fouling and wet bulb shift range, approach and water balance.

Trace airflow pickup, damper, actuator, reheat coil and thermostat in a pressure-independent VAV terminal, with automatic PI control, manual override and a stuck-actuator fault.

Operate a chiller, centrifugal pump, throttling valve and building coil in a closed chilled-water loop, and test what happens when the pump or chiller fails.

Trigger a fire alarm recall at the designated or an alternate landing and watch a single elevator car, controller and recall relays sequence Phase I recall.

Heat a thermistor sensing element and compare fixed-temperature against filtered rate-of-rise alarm decisions.

Follow an addressed detector's event through a supervised SLC, panel processing and alarm memory to a notification command.

Command an addressable relay to release a magnetic fire-door holder and verify the physical door response with independent position feedback.

Wire a 3-appliance radial NAC, inject open/short faults and read live voltage drop and end-of-line supervision.

Poll 6 addressed devices on a return-loop or radial SLC and see which survive an open, short or duplicate address.

Watch an off-axis photoelectric chamber fill with smoke and qualify a signal into a latched alarm.

Command a motorized exhaust damper and fan starter with open/airflow proof, jam faults, and check the model against a built-in verification suite.

Deflect a vane switch with riser flow, tune retard time and threshold, reject transients, and latch a panel alarm.

Command a supervisory BMS network — points, priority arrays, trend historian and alarm console — over a simulated building plant.

Move a device across three radio cells, trigger handover, and test registration, ping, DNS and download through the mobile core.

Send packets from a laptop through access, DNS and cloud infrastructure — inspect every hop with ping, traceroute and HTTPS tests.

Tip magnetization with RF pulses, encode position in k-space, and reconstruct a synthetic MR image while exploring T1/T2 contrast.

Dual-WAN edge router simulator — path monitoring, failure detection delay, route installation and preemptive restoration control outage duration.

Optical link-budget simulator — launch power, fiber attenuation, connector/splice loss and bend loss determine received power and receiver margin.

Stateful firewall appliance simulator — ordered rule evaluation, TCP handshake tracking and idle timeout decide whether traffic is allowed.

Four-port Ethernet switch simulator — source learning, unknown-unicast flooding, broadcast forwarding and dynamic-entry aging.

Trace enterprise, industrial DMZ and OT zone traffic across a firewall, jump host and PLC.

Elect a root bridge and watch port roles reorganize to remove a Layer 2 forwarding loop.

Trace 802.1Q trunk tagging, VLAN pruning and native VLAN mismatches across two switches.

Model an 802.11 access point and client through association, SNR and shared-airtime throughput.

Trace a 24 V PNP field switch through input qualification, a PLC read/execute/write scan cycle and an output module to a solenoid-driven cylinder.

Evaluate start permits on a guarded mixer, latch a first-out running trip, and practice restore-reset-restart sequencing.

Trace a two-wire pressure transmitter through cable and shunt resistance, an ADC and PLC scaling, and diagnose compliance limits and span mismatches.

Tune a PI level loop around a transparent tank with a modulating inlet valve, hydrostatic transmitter and gravity outlet.

Heat a process vessel and follow a qualified high alarm, a separately qualified high-high trip, and acknowledge/reset/rearm sequencing.

Ramp a slew-limited frequency command and watch synchronous speed, slip and the base-frequency torque envelope respond, with a drive-fault coast-down.

Bias a PN junction diode, sweep temperature and resistance, and read the real operating point off a live I–V curve and load line.

Wire two resistors series or parallel on a current-limited bench supply and watch branch currents, drops and resistor heating live.

Charge and discharge a capacitor through a series resistor, add parallel leakage, and watch exact first-order voltage and energy curves.

Energize a wound gapped-core inductor and compare flyback clamp voltages against decay speed and switch stress.

Common-emitter amplifier with a loaded bias divider, emitter degeneration and switchable AC bypass — compare input and inverted collector output.

Four discrete diodes rectify an isolated AC source — inject open-diode faults and compare full-wave vs. failed half-wave output.

Linear supply chassis with transformer, bridge, reservoir capacitor and load bank — measure real ripple instead of assuming perfect DC.

Two-layer sensor board from power connector and RC filtering through sample-and-hold conversion, serial transfer and PWM LED output.

NPN low-side LED driver — trace base drive through cutoff, forward-active and saturation regions, with PWM and fault injection.

Orifice-plate DP flow meter with impulse tubing, a three-valve manifold, and square-root extraction split across transmitter and receiver.

Fill and drain a vessel while comparing a hydrostatic DP transmitter (dry/wet leg) against roof-mounted radar time-of-flight sensing.

Calibration bench with hand pump, isolation/vent manifold, diaphragm transmitter and a powered 4–20 mA receiver — trace the full loop voltage budget.

Pt100 RTD vs. thermocouple sensing in a stirred bath — compare 2/3/4-wire lead compensation, cold-junction compensation and sensor faults.

Explore a double-acting piston cylinder — directional spool, cap/rod chambers, load spring, friction and end stops.

Compare cascade, single-loop and manual architectures on a heated vessel with a master temperature and slave flow PI loop.

Trace voted pressure sensors through a latched shutdown decision, solenoid, pump stop and a spring-return isolation valve with closure proof.

Compare a fail-closed and fail-open spring-return valve on the same demand, then lose air, power, or jam a stem.

Inspect a globe valve cutaway and compare linear vs. equal-percentage trim against the installed flow characteristic.

Cutaway 3D pump simulator — prime the casing, energize the motor and watch flow, head and power settle to the operating point.

Find where the pump curve meets the system curve and move the real operating point live.

Separate pressure, velocity and elevation contributions in a two-station head measurement bench.

Read gauge vs. absolute pressure on both sides of a pump and track the margin above vapor pressure.

Watch vapor bubbles form at the impeller eye and collapse as pressure recovers.

Build the NPSH-available balance term by term and compare it against a pump's NPSH3 curve.

Run a twin-pump station and see branch flows add at a shared header head.

Pass one flow through a two-stage booster train and add the stage head rises.

Close a valve and follow the pressure wave and its reflections through a reservoir–pipeline–valve system with a distributed elastic-wave calculation.

Compare a throttled pump/valve duty against a same-flow, speed-reduced reference case to see the modeled energy cost of throttling.

Follow a fluid parcel through pressure, velocity and elevation head changes on an instrumented three-station energy bench.

Accelerate flow through a metered throat, recover pressure downstream, and diagnose a differential-pressure flow meter.

Trace an injected dye thread to compare orderly laminar flow, the transition band, and turbulent mixing.

Compare inertial and viscous stress scales on a test-loop rig, choosing whether velocity or volume flow stays fixed.

Change flow, bore, length, wall roughness and viscosity and watch the pressure gradient, Darcy friction factor and dissipated hydraulic power respond.

Throttle a valve, foul a strainer and adjust elbow coefficients to see how local fitting losses add to distributed pipe friction.

Adjust discharge, channel geometry, bed slope and roughness, and solve for normal depth against critical depth and Froude number.

Compare a maintained-head discharge with an unfed draining tank, adjusting head, orifice diameter and discharge coefficient.

Adjust inlet flow, bore sizes, flow split and leak fraction, and introduce a deliberate meter bias to separate mass balance from indicated readings.

Adjust liquid depth, density, headspace pressure and probe position, and separate gauge from absolute pressure.

Rotate a slider-crank mechanism and compare exact piston displacement, velocity, acceleration and torque against rod-ratio and speed changes.

Hold the sun, ring or carrier stationary on an epicyclic gearset and see how the Willis relation sets the resulting speed and torque ratios.

Inspect a radial ball bearing under load and speed changes and read cage speed, ball-pass frequencies and L10 rating life.

Set pulley diameters, slip and tension on an open flat-belt drive and audit the result against the capstan traction limit.

Cutaway tie-rod hydraulic cylinder — pressure/flow lab with directional valve and relief branch.

Cutaway air cylinder lab — receiver, filter-regulator, 5/3 valve and compressible-flow model.

Guarded chain-drive bench — tooth ratio, pitch/chain-length selection, chordal action and a wear-inspection gauge.

Charge/coast/discharge flywheel bench — motor-generator, energy audit ledger and a mechanical brake.

Full 3D V8 cutaway — cross-plane crankshaft, valvetrain, firing order 1-8-4-3-6-5-7-2, cutaway/solid/single/explode modes and a live P-V indicator diagram.

Move a section through a pin-and-roller beam test frame and trace applied loads into support reactions, shear jumps, bending moments and elastic deflection.

Load a slender compression specimen and compare elastic critical Euler load against imperfection amplification as end restraints and length change.

Inspect a wall-mounted cantilever, compare an ideal clamp with a rotational-spring root, and trace shear, hogging moment and tip deflection.

Load a five-joint Warren-style truss, solve the stiffness model, and trace tension/compression through all seven members and both bearings.

Compare two identical beam benches under the same loads, differing only in end restraint, and watch hogging moments and deflection change.

Follow vertical load and overturning moment through a column, spread footing and compression-only soil interface with a Winkler spring-bed model.