Free mock exam
Earthing & Bonding — Level 3 Systems Design Practice
Free topic-focused mock exam: 30 random questions from a pool of 48 on Earthing & Bonding, drawn from the wider Level 3 Systems Design bank. 35-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
- 30
- Time limit
- 35 min
- Pass mark
- 70% · 21/30
- Question bank
- 48
Free, no sign-up. Retake as many times as you like — different questions each time.
Sample questions
01The primary purpose of earthing an installation is to:
- Aimprove the power factor of the supply
- Bprovide a path for fault current and limit touch voltages
- Cincrease the supply voltage to the installation
- Dreduce the installation’s energy consumption
Why: Earthing provides a fault-current path that enables protective-device operation and limits touch voltages.
02The main earthing terminal is the common connection point for:
- Acircuit CPCs, bonding conductors and the earthing conductor
- Bthe line and neutral conductors of the incoming supply, ahead of the main switch
- Cthe meter tails, the cut-out and the supply fuse only
- Dthe neutral conductors of every final circuit, brought back to one bar
Why: The main earthing terminal is where circuit CPCs, bonding conductors and the earthing conductor are connected together.
03A TN-S earthing system has:
- Aa combined neutral-and-earth conductor throughout, in supply and installation alike
- Bseparate neutral and earth conductors throughout, from the source
- Can earth electrode at the installation, in place of any supply earth
- Dno connection to the supply earth at all, the neutral being earthed locally
Why: TN-S has a separate protective conductor throughout, typically provided by the supply cable sheath.
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.
