Consumer Units
Installation · C&G 2365 Unit 305 · Premium section
A is not a box of breakers, it is a design decision made visible. Which circuits sit on which device, what happens to the rest of the house when one fault occurs, and whether the person standing in front of it in ten years can tell what is what — all of that is settled when the board is arranged.
Domestic in England and Wales must be in a non-combustible enclosure, which is why steel boards replaced plastic ones. Beyond the enclosure, the live choices are the protective arrangement: a split-load board with two , a high-integrity board keeping critical circuits apart, or an all- board where a single faulty circuit takes only itself out. Surge protection and arc fault detection sit in the same conversation.
Labelling is part of the installation, not paperwork bolted on afterwards. A circuit chart that matches reality, the warning notices a board is required to carry, and bonding connections marked so nobody removes them, are what make the next person's job safe rather than archaeological.
Common questions
- Is there a free Consumer Units quiz?
- 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 Consumer Units sit in the City & Guilds scheme?
- maps to C&G 2365 Unit 305. On TradeTraining it lives in the Installation section as bite-size lessons with practice questions.
- Why must a domestic consumer unit be in a metal enclosure?
- Because a loose connection inside a board can arc, and a plastic enclosure can sustain a fire that a non-combustible one contains. The requirement applies to in domestic premises; the practical effect is that steel boards are now the norm.
- What is a high-integrity consumer unit?
- An arrangement that keeps circuits apart so one earth fault cannot black out the whole installation — typically two -protected banks plus ways for circuits you never want to lose, such as the freezer, the boiler or a socket in the hall.