# TrafoCalc — Power Transformer Calculations

> Power Transformer Calculations (iPhone/iPad app by Mohd Dahnial Ismail.)

- Source: https://appshunter.io/ios/app/trafocalc/id6757797482 (this page in markdown: same URL + `.md`)
- Developer: [Mohd Dahnial Ismail](https://appshunter.io/developer/1868973164)
- Category: Utilities, Productivity
- Price: $0.99
- Age rating: 4+
- Requires: iOS 18.2 · 4 MB
- Languages: American English
- Released: 2026-01-16
- Data updated: 2026-09-08
- User reviews in markdown: https://appshunter.io/ios/app/trafocalc/id6757797482/reviews.md

## What is TrafoCalc?

TrafoCalc is a practical transformer calculation tool built specifically for field engineers, commissioning teams, and utility professionals.
Designed for real-world use at substations and test sites, TrafoCalc provides fast, reliable calculations without spreadsheets or manual formulas.
Key Features
• Rated current calculation (HV & LV, 3-phase)
• Transformer ratio calculation based on vector group
• Full tap-changer support (Tap 1 = highest voltage)
• Per-tap voltage and ratio calculation
• ±0.5% ratio tolerance range for testing reference
• Short-circuit current calculation
• Supports common IEC vector groups (Dyn, YNd, Yy)
• Clean, offline-ready interface
Built for Professionals
TrafoCalc follows IEC-based formulas and is suitable for:
• Factory Acceptance Tests (FAT)
• Site Acceptance Tests (SAT)
• OLTC verification
• Ratio testing reference
• Substation commissioning
No ads. No clutter. Just the calculations engineers actually need.


## Version history (last 2 releases)

### 1.0.1 — 2026-01-25

New vector group added, ZNyn1 and ZNyn11.

### 1.0 — 2026-01-16

No release notes.

## Apps similar to TrafoCalc

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [ActiveOBD](https://appshunter.io/ios/app/activeobd/id1524791245) | 3.6 (39) | Free | Utilities |
| [Spreadsheet Formula AI](https://appshunter.io/ios/app/spreadsheet-formula-ai/id6470530421) | 4.6 (58) | Free | Utilities |
| [TMP DVR II](https://appshunter.io/ios/app/tmp-dvr-ii/id1659597979) | — | Free | Utilities |
| [Vehicle Maintenance Tracker](https://appshunter.io/ios/app/vehicle-maintenance-tracker/id1315913699) | 4.3 (2,887) | Free | Utilities |
| [Thermal Xplorer](https://appshunter.io/ios/app/thermal-xplorer/id6450157809) | 1.8 (12) | Free | Utilities |
| [Thermal Mobile](https://appshunter.io/ios/app/thermal-mobile/id1590989268) | 1.9 (16) | Free | Utilities |

## More apps by Mohd Dahnial Ismail

- [TransZCalc](https://appshunter.io/ios/app/transzcalc/id6758698481)

All apps by Mohd Dahnial Ismail: https://appshunter.io/developer/1868973164

---

*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-09-08.*