Lineman's Reference - XFMR LAB
Digital Apprentice LLC Education iPhoneiPadiPod touch
Lineman's Reference - XFMR LAB is a paid Education app for iPhone and iPad by Digital Apprentice LLC. Rated 4.7/5 from 408 ratings. Requires iOS 16.0.
- Rating
- 4.7
- 408 ratings
- Price
- 19.99 USD
- on the App Store
- Size
- 65 MB
- Age 4+
- Updated
- Oct 21
- 2026 · v2.0.7
Screenshots
About Lineman's Reference - XFMR LAB
Learn it. Wire it. Energize it. Check your work. Built by a working journeyman lineman for linemen and their apprentices. The XFMR Lab simulates distribution transformer banks driven by your own wiring — the metering, fusing, and faulting all behave the way you'd expect in the field. NEW IN 2.0 — BUILT-IN TRANSFORMER TRAINING (Replacing XFMR INFO) Six guided lessons take you from "what's a transformer?" to wiring a 3-pot bank: • Start Here — What is a Transformer? • Dual H Bushings — The Two Wirings & the Nameplate • The Tap Changer — One Pot, Multiple System Voltages • Three-Phase — The Three Phases and How They're Related • Bank Identification — Delta or Wye, Open or Closed • Your First Bank: Delta-Wye Closed (120/208) • More lessons on the way! Work the lessons in order, or jump straight to the labs. ALSO NEW IN 2.0 • The Sandbox (Beta) — wire anything from scratch in a COMPLETELY-customizable lab, with live, vector-based voltage and fault logic baked in. • Death Traps — scenario-based transformer traps linemen run into — and how to navigate them safely. • A brand-new look across every lab — new graphics, sharper, faster, & easier to read in the field. • Voltmeter you can now drag with two fingers; readings update as the leads move. • Parallel the secondary coils by hand in wye secondary labs • Stats that track lab completions, quiz scoring and for-fun stuff like the number of fuses you've blown. • User Customizations - the user can now alter the spec of their labs; from grounding to parallel coil cutover-direction, requiring the 4th cutout, tap changer implementation and more. • 2.0 is FREE for everyone who already owns XFMR Lab — thank you for years of feedback and encouragement. WHAT YOU GET Single Phase — Single Bushing · Dual Bushing Three Phase (closed) — Delta-Delta · Delta-Wye · Wye-Delta · Wye-Wye Three Phase (open) — Open Delta-Delta · Open Wye-Delta Misc — Paralleling · 4th Cutout · Death Traps (6 Scenarios) Advanced — Straight 480 · 240/480 · 277/480 · Corner-Grounded 240/480 · Wye-Wye 5-Wire (120/240 + 120/208) - all now able to be wired up Wye AND Delta on the topside The Sandbox (Beta) EVERY FUTURE UPDATE IS FREE - THE APP IS A ONE-TIME PURCHASE. I'm always working on new updates. TOOLS & REFERENCE • Volt, ohm and rotation meters with real behavior • Nameplate, secondary coil and tap changer animations • Reference diagrams for every standard bank Learning Mode walks apprentices through every wrong-connection check. Journeymen and experienced users can keep this turned off if they'd like. QUIZZES • Classic Quiz — Select each lab you want in your quiz - with graded scoring across each lab. • Advanced Quiz — You're provided with the job-site info and need to pick the right nameplate and coil setup, then wire it. • Bank ID - A beginner's quiz tied into the new XFMR Training lesson plan. The user is provided with different primary and secondary wirings and must correctly identify them. Used by 30,000+ linemen since 2021. Questions? Suggestions? Reach me at [email protected]
Ratings & reviews
4.7
408 ratings
What’s new
Version 2.0.7 · Updated October 21, 2026
What's new in 2.0.7 - Sandbox: the Wye 5-Wire bank now builds a 50 kVA series pot behind the two 25s, the way it goes on the pole, and the ratings panel shows what that pot's two coils can carry. Overload a coil and the risk pill names it. - Sandbox: a wye bank whose pots were left in series reads its true usable capacity. - A privacy policy link in Settings. - Small fixes across the labs and the lessons.
App privacy
The developer, Digital Apprentice LLC, reported these privacy practices to Apple.
Data Not Linked to You
The following data, which may be collected but is not linked to your identity, may be used for the following purposes:
- Contact Info: Name
- Usage Data: Other Usage Data
Used for: App Functionality
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| App | Rating | Price | Last updated | Compare |
|---|---|---|---|---|
| Lineman's Reference - XFMR LAB | 4.7 / 5 (408 ratings) | 19.99 USD | October 21, 2026 | |
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