Lineman's Reference - XFMR LABios
Learn it. Wire it. Energize it. 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]

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#88
United States · paid
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As of Jul 23, 2026stale (56d)
Rating 4.35
Ratings 175
Price $19.99
Version 2.0.3
Updated Jul 4, 2026
Released Sep 12, 2021

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v2.0.3Jul 4, 2026
XFMR Lab 2.0 — the biggest update since launch. NEW: Built-in Transformer Training (replaces XFMR Info). Six guided lessons take you from "what's a transformer?" to wiring a 3-pot bank — Start Here, Dual H Bushings, The Tap Changer, Three-Phase, Bank Identification, and Your First Bank: Delta-Wye Closed. More lessons on the way. More lessons on the way soon! NEW: The Sandbox (Beta) — wire anything from scratch in a fully customizable lab, with live, vector-based voltage and fault logic baked in. NEW: Death Traps — scenario-based transformer traps linemen run into, and how to navigate them safely (3 scenarios with more on the way). NEW: User Customizations — set the spec of your own labs: grounding, parallel coil cutover direction, requiring the 4th cutout, tap changers, and more. NEW: Bank ID quiz — a beginner quiz tied to the Training lessons; identify primary and secondary wirings on sight. NEW: Stats — track lab completions, quiz scores, and for-fun numbers like how many fuses you've blown. ALSO: • A brand-new look across every lab — new graphics, sharper and easier to read in the field. • Tap changer, nameplate, and secondary coil animations. • Parallel the secondary coils by hand in wye-secondary labs. • Advanced labs can now be wired Wye OR Delta on the topside. • Voltmeter now drags with two fingers; readings update as the leads move. 2.0 is FREE for everyone who already owns XFMR Lab — and every future update is free, too. One-time purchase. Thank you for years of feedback and encouragement.

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