Free mock exam

Level 3 Fault Diagnosis Mock Exam

Free mock exam for Level 3 Electrical apprentices on Fault Diagnosis. 25 questions from a 251-question bank covering the logical fault-finding sequence, dead vs live testing, multifunction tester use, common fault types (high Zs, low IR, RCD nuisance tripping, broken neutral) and how each maps to EICR observation codes.

Questions
30
Time limit
35 min
Pass mark
70% · 21/30
Question bank
250

Free, no sign-up. Retake as many times as you like — different questions each time.

Sample questions

  1. 01What type of fault occurs when current flows through an unintended path of low resistance?
    • AEarth fault
    • BShort circuit fault
    • CHigh resistance joint
    • DOpen circuit fault

    Why: A short circuit fault occurs when current bypasses the normal load path through an unintended low resistance connection, causing excessive current flow.

  2. 02An open circuit fault would typically be identified by:
    • AWarm cables along the run
    • BReduced brightness at the lamp
    • CA tripped MCB at the board
    • DNo voltage at the load

    Why: An open circuit fault breaks the current path completely, resulting in no voltage reaching the load equipment.

  3. 03What is the primary danger of a high resistance joint?
    • ANo danger if protected by fuse
    • BFire risk from overheating
    • CVoltage drop only
    • DImmediate circuit breaker trip

    Why: High resistance joints generate heat when current flows through them (P=I²R), creating a significant fire risk as they may not be detected by protective devices.

Common questions

Is the Level 3 Fault Diagnosis 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.

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