Transformer turns ratio and voltage regulation
Ideal winding ratio and a per-unit series regulation estimate. Motor and generator calculators stay listed on the same hub.
Electrical thinking, made visible
Electrical engineering calculators and energy tools
Explore transparent engineering estimates that connect every input to a method, result, and boundary.
52 live calculators8 teaching cases100% inspectable inputs
Live modelReady
Voltage12 V
Current2 A
Power24 W
Eight ways in
Start with the decision in front of you.
From a single circuit to an energy investment, each category keeps the path focused.
01
Fundamentals
Start with voltage, current, resistance, reactance, and time-domain behavior.
Explore 02Wiring
Explore circuit behavior, conductor resistance, and voltage-drop candidates.
Explore 03AC power
Make real, reactive, and apparent power easier to see and compare for balanced single-phase and three-phase systems.
Explore 04Machines
Explore transformer ratio, voltage regulation, and related machine calculations with the assumptions stated on each tool.
Explore 05Battery & UPS
Frame stored energy, charge time, load capacity, and runtime assumptions.
Explore 06Solar & storage
Connect solar generation, storage, tariffs, and a simple project payback estimate in one category.
Explore 07Energy use
Understand what uses energy, what it costs, and how alternatives compare.
Explore 08Efficiency
Compare losses, correction, energy savings, and lifecycle cost scenarios.
ExploreAvailable now · Fundamentals
One simple law.
Four useful quantities.
Enter any supported pair and move between voltage, current, resistance, and power—with formula evidence beside the result.
Open the calculator12volts
÷6ohms
=2amperes
Power = 12 V × 2 A = 24 W
Featured Engineering Topics
Five topics, on the category pages that already exist.
No second set of topic URLs. Each card opens the existing category and the two guides written for that question.
Balanced three-phase power and power factor
Active, reactive and apparent power for a balanced system, plus lagging-load vars. Fault current stays on the wiring hub.
Cable voltage drop and thermal current
Loop voltage drop and a parameterized thermal-current estimate. The hub also keeps protection screens that are not cable models.
Battery runtime and UPS sizing
Constant-load watt-hours and the separate UPS sizing-and-runtime model. Shared storage tools also appear under solar.
Solar payback and string voltage
Monthly generation to a simple payback, and string Voc at the temperatures you enter. Shared battery tools remain on this hub.
Teaching cases
See the reasoning, not just the answer.
Static, reproducible examples based on the project’s calculation specification—not customer projects or field measurements.
CASE-001 · Teaching fixture
Voltage Drop for a Long Cable Run
Follow a transparent DC teaching fixture from conductor resistance to end voltage.
Read the caseCASE-002 · Teaching fixture
Cable Cost and Loss Comparison
See how a higher initial teaching cost can pair with lower modeled energy loss.
Read the caseCASE-003 · Teaching fixture
Residential Solar Energy and Payback
Trace a manual monthly generation profile through self-use, export, and simple payback.
Read the caseDesigned for depth
From circuits to whole-energy choices.
The planned catalog follows the same standard: clear assumptions, inspectable math, readable comparisons, and honest limits.
See what comes next