I’m an amateur and I self-studied using a textbook plus YouTube explainer videos.
This article covers what the Class 2 Electrician’s License is, how I got it, and what it cost in total.
What’s the Class 2 Electrician’s License?
In short, it’s a Japanese national license that authorizes you to do home wiring work.
For example, replacing one of those old “Showa-era” light switches with a modern one (photo below) legally requires a Class 2 Electrician’s License in Japan.
Some “minor work” is exempt and can be done without a license. For example, plugging cables into an outlet:
But most other wiring work in your home requires the license.
(Per Japan’s Electrician’s Act.)
Why I Decided to Get It
For me it expands what I can do as part of DIY.
The trigger was researching how to swap an old “Showa-era” switch for a modern one. Quick search → in Japan, even your own home requires a license to do that.
“It’s my house — surely I can mess with my own wiring, right?”
Apparently, no. Japanese law says you can’t.
And I obviously can’t blog about doing it without one.
(Side note: a British friend told me the UK lets you mess with your own house freely without a license. I have no idea if that’s actually legal there, but interesting.)
So:
“Fine, I’ll just go get the license. It sounds fun.”
And I signed up for the test.
(I have a separate Japanese article on actually swapping a Showa switch for a modern one — English version forthcoming.)
The Path to the License
As of 2022, the test runs twice per year — first half and second half. I looked into it, found that registration for the first-half test opens around March, and signed up in March.
The exam has two parts: written exam and practical (hands-on) exam.
Pass the written, and you advance to the practical.
The “Electrical Engineers Examination Center” (一般財団法人 電気技術者試験センター) administers the test. Sign-up cost: 9,300 yen (~$60). You also create an account on their site and upload a photo.
1万円 already spent — failure was not an option.
Time to study for the written exam. (At this point I didn’t yet realize how much more I’d be spending on textbooks and tools later…)
Written Exam
Textbook
I searched Amazon for “Class 2 Electrician textbook” and bought the top result.
“Class 2 Electrician’s License — Written Exam: Sui-tto Pass” (2,090 yen).
Six chapters in priority order, lots of diagrams, very accessible.
What score do you need?
It’s a multiple-choice test, 50 questions, and you need to get 30 right (60%) to pass.
So I didn’t aim to master any one section perfectly — I covered the entire range.
(If you’re a non-engineer / non-math type and you find “basic electrical theory” topics like resistivity and circuit analysis painful, honestly you can skip those — 60% is enough to pass.)
Per the textbook’s intro, the best loop is: read a chapter’s explanation → immediately do the past-exam questions in the back. Repeat. I started with chapter 1, got a feel for time-per-chapter, and paced myself to finish all 6 chapters by exam day, studying mornings (I’m a morning person).
Side tip — about “complete wiring diagrams”
The written exam tests you on “complete wiring diagrams” (複線図, fukusen-zu). A “single-line diagram” is a simplified schematic of how devices connect; a “complete wiring diagram” is the actual every-conductor wiring representation.
Complete wiring diagrams are tricky at first, but they’re worth studying.
Reason: drawing the complete wiring diagram from a single-line diagram is essential for the practical exam.
You’ll have to learn it eventually for the practical, so you may as well learn it during written-exam prep.
Taking the written exam
The 2022 first-half written exam was on Sunday, May 29. I live in Saitama, and the venue was Saitama University. The campus had club recruitment posters everywhere — peak nostalgia. Made me wistful that I’ll never be a college student again. Maybe after retirement I’ll re-enroll?
Results posted online about 2 weeks later (June 13).
→ Passed!
For 2022 first half, written exam: 78,634 sat, 45,734 passed — 58.2% pass rate.
Practical Exam
Pass the written, advance to the practical.
Overview
40-minute time limit. Successfully build the wiring per the given problem to pass.
The exam provides cables, switches, and other components — but you bring your own tools.
The practical is a single defect anywhere = automatic fail. High pressure.
“Strict!” was my reaction. But honestly — if you hired an electrician for your house, you wouldn’t accept “there are some defects but it’s 70% done, so OK”? So fair enough.
“Candidate problems” — known in advance
The official site publishes 13 candidate practical problems — your exam will be one of those 13.
So you can prepare specifically.
Practical exam prep
Lots of options for studying — books, web resources, etc. I used the explainer pamphlet that came with my tool kit, plus the corresponding YouTube videos.
Tools
I have woodworking tools from DIY, but electrical work needs different tools.
Searching online, I found that HOZAN sells a tool kit specifically for the Class 2 Electrician practical. I bought it on Amazon (12,000 yen).
(Plenty of test-takers at the actual exam venue had this same kit.)
Practice cable and parts
There are bundled practice cable + components sets for sale, so I bought one — also Amazon.
“Class 2 Electrician Practical Exam — Practice Material Set (1 round of cables + components)” — about 15,000 yen.
I ran out of cable while practicing, so I bought more.
This second set was pre-cut to expected lengths and packaged per problem — really easy to use. Amazon, 8,800 yen.
Practicing
HOZAN (the tool kit company) also runs a YouTube channel called “Denko Shiken no Tora” (電工試験の虎) with videos on tool usage and step-by-step builds for all 13 candidate problems.
I leaned on those videos pretty much exclusively.
If you watch them, the host’s tone is just-right — neither overhyped nor monotone. You’re going to rewatch these a lot, so that actually matters.
As mentioned, the 13 candidate problems are public, and one of them is your exam. But memorizing all 13 wirings outright isn’t realistic.
The right approach: get really comfortable converting the exam’s single-line diagram into a complete wiring diagram, and then build from that.
After studying individual operations for a while, I tried doing one full problem end-to-end — over an hour. (Exam is 40 minutes.) Yikes.
So I drilled night after night.
By the end I was finishing with about 7 minutes to spare.
Defect criteria
Even one defect = automatic fail. The official site lists exactly what counts as a defect — required reading.
Taking the practical
2022 first-half practical was Sunday, July 24.
One step in the practical involves mounting a switch in a “modular mounting frame” (連用取付枠). I drew the wiring diagram first, then went straight to mounting the switch — but I tightened it down before the switch was fully seated. Probably nerves.
I removed the switch, intending to reseat it properly, retightened — and somehow it still wasn’t fully seated. Round three.
This was where I started to panic.
The mounting frame is held by deformable metal tabs you bend with a flat-head screwdriver. Repeatedly loosening and tightening will eventually break them.
And if it breaks: defect → instant fail. (And the exam had barely started.)
I went super delicate on the third try, careful not to add stress. The mounted switch had a tiny bit of play (slight rattle when tapped) but I was too scared to push the frame any further. Hopefully a tiny rattle is fine.
After that I got into a flow with the wiring and recovered mentally. Finished within the time limit.
Hard part of practice (and the exam): self-judging whether the wiring is correct and defect-free is tough…
Passed!
Online results released August 18 → Passed!
The official site says, in delicately roundabout Japanese, “your number appears in the pass list” — that’s the pass message.
I’d put serious time into practice, so passing was a real relief.
The official certificate arrives by mail later.
For 2022 first half, practical: 53,558 sat, 39,771 passed — 74.3% pass rate.
License issuance is the last step — there’s a 5,300 yen issuance fee…
Total Cost
Main costs to get the Class 2 Electrician’s License:
・Exam fee: 9,300 yen
・Written exam textbook (“Sui-tto Pass”): 2,090 yen
・Practical exam tool kit (HOZAN): 12,000 yen
・Practice cable + components (Mozu series, 1 round): 15,000 yen
・Additional practice cable (Pro Support set): 8,800 yen
・License issuance fee: 5,300 yen
(Plus train fares, etc.)
Total: 52,500 yen (~$350).
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