The wire can never be smaller than the breaker allows. Electricians make that call every day. Five questions per round, get four right to pass. Pick your country and the questions use its wire size unit, or switch the unit yourself.
Wire sizing down? The next step is the licensing exam: take a practice test for the country you picked.
Take an electrician practice exam Taking the Texas Journeyman exam? Get the practice pack (US$39)
Signed-in members who pass on the site earn 5 learning points, once a day.
Practice questions based on common reference tables. Real installations must follow local code, installation method, ambient temperature and conductor-count corrections, and be decided by a qualified electrician.
