SunStem vs E

SunStem is an offline solar and battery calculator for RVs, vans, boats and cabins. Build a saved system profile, then estimate battery runtime, solar yield, reserve risk and safer system sizing on iPhone or iPad. CALCULATE BATTERY RUNTIME - Compare load, solar and usable battery capacity - Forecast the next charge window and hours to the reserve floor - Work offline from a saved profile and local inputs SIZE AN OFF-GRID SYSTEM - Review battery, PV, MPPT, inverter, wire and fuse planning outputs - Check voltage drop, cold Voc and fuse-versus-wire safety gates - See assumptions and deterministic calculations from the native core AUDIT THE NEXT SEVEN DAYS - Scan daily reserve risk from saved load and solar assumptions - See what to shed, when to charge and why the risk changed - Export facts for a trip partner, installer or hardware review No cloud account is required before first value. SunStem provides planning estimates and field-review evidence, not engineering certification. It does not control chargers, inverters or BMS hardware. Background or unattended hardware monitoring is not promised in this release.

E-Light looks simple. It solves like an engineer. Learn electrical engineering by building real circuits. E-Light combines an interactive circuit simulator with professional electrical calculators into a single modern learning platform. At the heart of E-Light is a circuit simulator powered by a real Modified Nodal Analysis (MNA) physics engine. Place industrial electrical components onto the canvas, connect them terminal-to-terminal, press Run, and watch your circuit come alive with live voltage, current, and power calculations. ◆ THE SIMULATOR ◆ The heart of E-Light ▸ A real MNA physics engine solves the entire circuit on every change — series, parallel, and three-phase. ▸ 125+ real industrial components: contactors, MCBs, RCDs, overload relays, VFDs, timers, 3-phase motors, sensors, CTs, energy meters, and more. ▸ Make it fail safely: overload a breaker, and it trips; drop a phase, and the relay reacts — zero risk, zero smoke. ▸ Live readouts for voltage, current, power, and energy, like a real test bench. ▸ Practice motor-control wiring: start/stop, delay timers, and seal-in circuits. ◆ PROFESSIONAL ENGINEER-GRADE CALCULATORS ◆ When you need a fast, defensible answer, 20 are built in: • Ohm's Law • Power (1Φ / 3Φ) • Voltage Drop • Wire Size • Motor FLC • Breaker Sizing • Short Circuit • Ground Fault Loop • Relay IDMT • Power Factor Correction • VFD Speed • Earthing Conductor • Busbar Sizing • UPS Sizing • Battery Backup • Generator Sizing • Generator Fuel • Residential Load • Lighting Design Built to recognized standards. With Pro, each calculator also reveals the equation behind the result, so you can check the formula, not just the number. ◆ BUILT FOR LEARNING ◆ Designed for engineers, technicians, educators, and students who want to learn, and instructors who want a safe, zero-equipment lab in the classroom. Practice and better understand electrical systems in a safe digital environment. ◆ FREE & PRO ◆ The simulator and all 20 calculators are free to use, with 10 components to try the canvas, local project saves, and occasional ads. E-Light Pro removes ads, reveals the formula behind every calculator, and unlocks the full 125+ component library plus cloud sync — start a circuit on one device and continue on another. ◆ GROWING WITH EVERY UPDATE ◆ New simulator components, calculators, languages, and features continue to be added. ◆ WORKS ACROSS YOUR DEVICES ◆ Sign in once, and your projects sync across Mobile > Desktop > Tablet. Start a circuit on one device and continue on another. ◆ E-LIGHT PRO ◆ (auto-renewing subscription) Unlock the complete simulator component library, cloud sync, an ad-free experience, and calculator formulas. • Available as Monthly, Quarterly, or Annual plans • Prices are shown in the app and may vary by region • Payment is charged to your Apple ID upon confirmation of purchase • Renews automatically unless auto-renew is turned off at least 24 hours before the end of the current period • Your account will be charged for renewal within 24 hours prior to the end of the current period • Manage or cancel anytime in your App Store account settings Terms of Use (EULA): https://elight.app/terms Privacy Policy: https://elight.app/privacy