BUILT FOR THE FIELD. GROUNDED IN ENGINEERING.
LEO FIELD TOOLS
Professional Engineering Suite
Plan the system. Understand the numbers.
Make informed decisions on site.
SURVEILLANCE · POWER · DIAGNOSTICS
Independent tools. One trusted standard.
Leo's Safety Shop LLC
Independent tools. One trusted standard.
Leo's Safety Shop LLC
Your field workspace
02 ACTIVE MODULES01 / SYSTEM PLANNING
Solar Engineering
Energy Production, Battery Banks & Autonomy
Open engineering workspace
02 / MEASURE & COMPARE
Battery Diagnostics
LiFePO4 Testing & Battery Health Analysis
Open Leo Battery · separate app
Next in the suite
COMING SOONElectrical Calculator
Coming soonNetwork Tools
Coming soonCCTV Designer
Coming soonSignal Analyzer
Coming soonTrailer Route Manager
Coming soonField Reports
Coming soonLocal-first workspaceOffline Solar Engineering after cachingNo account required
Leo Battery is an external application with separate storage. Its offline availability is not provided by this app.
01 / SOLAR ENGINEERING
Build a clearer power plan.
Runtime —View results ↓
Battery bank designer
STORAGE / DCUse identical batteries with matching chemistry, capacity, age and state of charge. Verify the manufacturer's permitted series/parallel configuration, BMS limits, balancing, conductor sizing and protection. A calculated configuration is not an approval to connect it.
Depth of discharge is an energy budget, not a voltage-to-state-of-charge conversion. Chemistry selection does not invent manufacturer limits.
Equipment load schedule
ACTUAL SPECIFICATIONSEnter measured or documented input power at the equipment supply. No manufacturer power values are prefilled. Average demand spreads each daily schedule across 24 hours; it does not establish an hourly operating profile.
The initial 200 W load is an illustrative test case, not a specification for any product.
Solar array calculator
ENERGY / DAYPeak sun hours are equivalent full-sun hours, not daylight duration. Confirm local season, panel condition and measured charge-controller data. Availability models the functional deployed portion of the array, including folded, damaged or disconnected panels.
Shading is modeled as an aggregate percentage. Series-string shade, bypass diodes, MPPT limits, temperature and controller clipping can cause nonlinear losses that this estimate does not model.
Nighttime & charging recovery
CONDITIONS / SOCRecovery uses stored battery energy and subtracts simultaneous equipment demand. Daily recovery includes a full 24-hour load budget. Solar-equivalent charging hours describe charging conditions only and do not include intervening nights, tapering, weather or BMS restrictions.
Field troubleshooting
WHAT-IF ANALYSISEach scenario compares an explicit example with your current plan. Applying it changes only this local calculation; it does not control equipment.
Opening independent local storage…
YOUR LOCAL WORKSPACE
Saved work
Calculations and equipment presets stay in this browser at this address. Export backups before changing devices or clearing browser data.
Saved calculations
Equipment presets
Backup & recovery
Imports merge saved calculations and presets without replacing your current plan. A previous local snapshot is retained after each successful write. Browser storage can still be removed by the device; keep exported backups private.
ENGINEERING / FIELD GUIDE
Understand the model.
Series and parallel
Series adds voltage and retains Ah. Parallel adds Ah and retains voltage. Two 12.8 V, 300 Ah batteries in series produce 25.6 V, 300 Ah and 7.68 kWh. The same pair in parallel produces 12.8 V, 600 Ah and 7.68 kWh.
Energy accounting
Nominal energy = bank voltage × bank Ah. Usable output energy = nominal energy × depth of discharge × downstream system efficiency. Operational energy = usable output energy minus the selected reserve. Autonomy = operational energy ÷ average equipment watts.
Collected solar energy = array watts × peak sun hours × functional deployed fraction × (1 − shading) × (1 − orientation / soiling losses) × controller / wiring efficiency. Stored charging energy also accounts for charging efficiency. Daily balance converts stored solar energy through downstream efficiency before subtracting equipment demand. Losses are applied multiplicatively.
Operating conditions matter
Runtime assumes the bank begins full unless the result explicitly references current SOC. Nighttime estimates use the average daily load unless you enter a separate measured nighttime average. Overnight scheduling, inverter peaks, battery temperature, aging, weather, Peukert effects and BMS cutoffs require field verification.
Installation and offline use
On iPhone, open this app in Safari, tap Share, choose Add to Home Screen, then tap Add. Open the installed app online once and wait for “Offline ready” before relying on offline Solar Engineering. On Android, use the browser's Install app or Add to Home screen option.
Leo Battery opens a separate website. This app neither copies its records nor guarantees its offline availability. Back up each app separately.
Data protection
No passwords, secrets, analytics, third-party scripts, cloud databases or account credentials are stored here. Your local records may contain trailer or project identifiers. Protect JSON exports and avoid private browsing for persistent field records.
Diagnostic work
Record charging current and voltage, confirm array deployment and shade, check fuses and connections, and review BMS / controller logs. Do not bypass protection or repeatedly reset an unexplained low-voltage shutdown. These tools do not replace qualified electrical review or manufacturer safety instructions.