Earthing & Bonding
Installation · C&G 2365 Units 203/305 · Premium section
connects an installation's exposed metal parts back to the source, so when a live conductor touches a casing, a large fault current flows and the protective device disconnects — that's . Bonding is different: it ties extraneous metalwork like incoming water and gas pipes to the same potential, so a fault can't leave two things you're touching at dangerously different voltages.
The system arrangement — , or TT — decides where that fault path runs and how good it is, which is why the same house rewire can need different protection in different streets.
Our questions drill the distinction, the conductor names and the system types until you can explain them to a customer in one breath — which is roughly what a 2365 assessor wants too.
Common questions
- Is there a free Earthing & Bonding quiz?
- & Bonding sits in the Installation section, which is part of TradeTraining Premium — but the app is free to start, sample questions are open to everyone, and the free sections cover the fundamentals first.
- Where does Earthing & Bonding sit in the City & Guilds scheme?
- & Bonding maps to C&G 2365 Units 203/305. On TradeTraining it lives in the Installation section as bite-size lessons with practice questions.
- What is the difference between earthing and bonding?
- provides a deliberate path for fault current back to the source so protective devices disconnect quickly. Bonding connects touchable metalwork together so it all sits at the same potential during a fault. Earthing clears faults; bonding limits the voltage between things you can touch while the fault lasts.