Free mock exam
Polarity & Functional Testing — C&G 2391 Inspection & Testing Practice
Free topic-focused mock exam: 20 random questions from a pool of 20 on Polarity & Functional Testing, drawn from the wider C&G 2391 Inspection & Testing bank. 25-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
- 20 questions
- Time limit
- 25 min
- Pass mark
- 70% to pass (14/20)
- Bank size
- 20 question bank
Free · no sign-up · timer can be ignored · retake as many times as you want
Sample questions
01What is polarity testing?
- A.Verifying correct connection of phase, neutral and earth conductors
- B.Verifying the continuity of the ring final circuit
- C.Verifying the earth fault loop impedance at each point
- D.Verifying the insulation resistance between live conductors
Why: Polarity testing verifies that phase, neutral and earth conductors are correctly connected.
02Why is correct polarity important for single-pole switches?
- A.To ensure the switch breaks both phase and neutral
- B.To ensure the switch breaks the neutral conductor
- C.To ensure the switch breaks the phase conductor
- D.To ensure the switch breaks the earth conductor
Why: Single-pole switches must be in the phase conductor to isolate the load when switched off.
03What could happen if polarity is reversed at a socket outlet?
- A.The circuit will draw twice its normal current
- B.The earth conductor will carry the full load current
- C.Risk of shock when maintaining equipment that appears off
- D.The RCD will trip every time the socket is used
Why: Reversed polarity means the neutral is switched, leaving equipment live even when switched off.
FAQ
Is the Polarity & Functional Testing 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.
