Free mock exam
Earthing & Bonding — 18th Edition (BS 7671) Practice
Free topic-focused mock exam: all 15 questions on Earthing & Bonding, drawn from the wider 18th Edition (BS 7671) bank. 60-minute timer, 70% to pass, worked explanation on every question. Use this when you've taken the full mock once and want to drill the topics you got wrong.
- Questions
- 15
- Time limit
- 60 min
- Pass mark
- 70% · 11/15
- Question bank
- 15
Free, no sign-up. Retake as many times as you like — the questions are reshuffled, with the answer order changed.
Sample questions
01Before commencing work, what must be established about the installation?
- ASupply characteristics and earthing system
- BThe original installer of the consumer unit
- CThe exact age of every cable installed
- DThe energy supplier and tariff in use
Why: Knowing the supply characteristics (Uo, frequency) and earthing arrangement (TN-S, TN-C-S, TT) is fundamental to designing protection and working safely.
02You discover a protective conductor is not continuous. What action should you take?
- AIncrease the protective device rating to compensate
- BRecord the defect and inform the responsible person
- CReplace the conductor with a larger line conductor
- DContinue testing and note it on the next inspection
Why: A discontinuous protective conductor is potentially dangerous; it must be recorded as a defect and the responsible person informed so it can be remedied.
03The minimum cross-sectional area for a main earthing conductor in a domestic installation is:
- A16mm²
- B6mm²
- C4mm²
- D10mm²
Why: The minimum size for a main earthing conductor is typically 10mm² for domestic installations.
Common questions
Is the Earthing & Bonding mock exam free?
Yes — 100% free, no sign-up needed. Questions are pulled at random from a substantial bank, with a worked explanation on every question after you submit.
Can I retake the mock exam?
Yes. Every attempt picks a different random selection and reshuffles the options, so each retake gives you genuinely new questions. No limit on retakes.
Does this count towards the real qualification?
No — this is independent practice material. To gain the actual qualification you need to sit the official assessment through an approved provider.
