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Table 537: which device for which kind of switchingCan a plug and socket be emergency switching?
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Chapter 46 names four kinds of isolation and switching: isolation (462), functional switching (463), switching off for mechanical maintenance (464) and emergency switching (465). Table 537.4 has columns for three of them, and they are not interchangeable:
| Type | What it is for |
|---|---|
| Functional switching | Everyday on and off, in normal use |
| Emergency switching | Cutting the supply fast, to remove a hazard |
| Isolation switching | Making a circuit safe to work on |
BS 7671 · Table 537.4 sets out which devices are acceptable for each. For functional switching, for example, it marks fuses, disconnectors, luminaire connecting devices and luminaire supporting couplers No, and switch-disconnectors and isolating switches Yes.
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