CSLB Electrical (C-10)

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A 100-question, 3.5-hour simulation to test your readiness.

Free practice for the California CSLB C-10 Electrical trade exam — the craft/classification test you take in addition to the Law & Business exam. Original questions in English, 中文 and Español, with 2023 NEC / 2025 California Electrical Code references.

Sen Lin, PrepPass Founder · Verified against California CSLB · How we review
Reviewed by Abraham Chen — Licensed California Electrical Contractor (C-10) (CSLB License #1142431 — verify)
To get a C-10 Electrical license you must pass BOTH exams — the Law & Business exam and this C-10 Electrical trade exam. Both are about 3.5 hours at a PSI center. CSLB does not publish the exact question count or passing score for the trade exam; you're told the passing mark at the test site.
Studying in order?

Practice stays free. The full CSLB Class C-10 — Electrical (Trade Exam) study guide is the material itself, taught start to finish — a downloadable PDF + EPUB you keep.

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What the C-10 trade exam covers

24%
Branch Circuits & Wiring
branch circuits · GFCI/AFCI · raceways · box & conduit fill · ampacity · voltage drop
22%
Services & Distribution
services · feeders · load calcs · grounding & bonding · OCPD · transformers
22%
Equipment & Systems
motors · HVAC · lighting · generators · solar · pools · low-voltage
12%
Planning & Estimating
plan & one-line reading · load-calc methods · permits · estimating
12%
Safety
Cal/OSHA · lockout/tagout · arc-flash PPE · working space · trenching
8%
Testing & Troubleshooting
meters · Ohm's law · fault diagnosis · grounding checks · terminations
Study guide →Browse all questions →CSLB Law & Business exam →

Frequently asked questions

Is PrepPass's CSLB Electrical (C-10) Trade practice free?

Yes — every CSLB Electrical (C-10) Trade practice question, study guide, and lesson on PrepPass is free. A full timed mock exam is also included at no cost.

How many CSLB Electrical (C-10) Trade practice questions does PrepPass have?

PrepPass currently has 521 original CSLB Electrical (C-10) Trade practice questions across 6 topic areas, and every question comes with a written answer explanation.

What languages is PrepPass's CSLB Electrical (C-10) Trade prep available in?

English, 中文 (Chinese), Español (Spanish), and Tiếng Việt (Vietnamese).

How are PrepPass's CSLB Electrical (C-10) Trade questions written?

They are original questions written by PrepPass from public-domain statutes and official exam blueprints — never copied from the real exam. Read our question methodology →

Is PrepPass affiliated with the licensing board or exam provider?

No. PrepPass is an independent study resource and is not affiliated with, endorsed by, or connected to any licensing board or official exam provider.

Can I practice CSLB Electrical (C-10) Trade on my phone?

Yes — PrepPass runs in any mobile or desktop web browser, with no app to download.

Own the complete CSLB Class C-10 — Electrical (Trade Exam) guide — PDF + EPUB, $14.99 →

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