Volt Drop Check & Plug
Voltage Drop & NEMA/IEC Guide
Only for iPhone
$0.49 · Designed for iPhone. Not verified for macOS.
iPhone
Voltage drop, cable sizing, ampacity, breaker selection, power conversion, and a NEMA/IEC plug reference — all in one iPhone app. Japanese/English UI. Works offline.
Volt Drop Check & Plug is an iPhone-only electrical calculation toolkit for field electricians, maintenance technicians, and design engineers. Stop juggling paper tables, calculators, and spreadsheets — switch between tabs and get the answer you need in seconds.
■ What's inside
1) Voltage Drop Calculator
• Inputs: supply voltage, load current (or power in W), cable length, conductor material (copper / aluminum), insulation (PVC 70°C, XLPE 90°C, heat-resistant PVC 105°C), circuit type (DC / 1-phase 2-wire, 3-phase 3-wire), power factor, and optional reactance.
• Outputs: ΔV, drop %, terminal voltage, loop resistance, and assumed conductor temperature.
• GOOD / CAUTION / NG verdict badge with a one-line explanation, improvement suggestions, risk notes, and basis notes.
• Round-trip ×2 applied automatically for DC / single-phase; √3 factor applied for three-phase.
2) Cable Size Selection (reverse calculation)
• From load current, voltage, cable length, allowable drop %, material, circuit type, power factor, and ambient temperature, get the minimum required conductor area and a recommended cable size.
• Side-by-side comparison of common sizes with PASS / FAIL / BEST indicators.
3) Ampacity Calculator
• From conductor material, size, installation method (free air / in conduit / bundled), insulation type, ambient temperature, and grouping count, see base ampacity with temperature and grouping correction factors.
• Corrected ampacity plus a per-installation-method summary.
4) Breaker Selection Guide
• From circuit current, circuit voltage, usage (general load / motor / lighting / IT·server), and phase (single / three), get a recommended rating (AT), frame size (AF), and type (MCCB / MCB / ELCB).
• Earth-leakage (ELCB) recommendation is highlighted automatically where appropriate. Includes a type guide.
5) Power Calculator (W ↔ VA ↔ kVA ↔ var)
• Convert between active power (W / kW), apparent power (VA / kVA), reactive power (var / kvar), and phase angle φ from voltage, current, and power factor.
• Three input modes: V×A, W, or VA. Single-phase / three-phase switchable.
6) NEMA / IEC Plug Quick Reference
• A searchable cheat sheet for plugs and connectors — useful for overseas sites and imported equipment. Filter by code, voltage, and more.
■ Designed for the field
• One-tap Japanese / English UI toggle (selection is remembered).
• All calculations run on-device — works reliably even with poor signal.
• Clear separation of inputs and results, with verdict badges and plain-language notes.
• iPhone-first layout tuned for one-handed use.
■ Great for
• Field electricians and contractors
• Facility and maintenance technicians
• Plant and building-services engineers
• Solar, energy-storage, and EV-charging designers
• Teams working with imported or overseas equipment
• Electrical students and trainees
■ Important
Results are reference values based on generic targets (e.g., 3% voltage-drop goal, 5% maximum). Always follow your local codes, internal standards, and equipment specifications for actual design and installation.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Improved usability
Significant enhancements to various features
The developer, MASAHIRO HIRAIWA, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- MASAHIRO HIRAIWA
- Size
- 37 MB
- Category
- Utilities
- Compatibility
Requires iOS 15.1 or later.
- iPhone
Requires iOS 15.1 or later. - iPod touch
Requires iOS 15.1 or later. - Mac
Requires macOS 12.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Copyright
- © 2025 Hiraiwa
