Arc fault interrupting breakers (USA relevant)
In a (much) earlier post, AFCI breakers were described thus (with a bit of paragraph compression):
The main reason is that the US uses wirenuts. Which are utter shit. Other types of joint tend to fail in safer ways, partly because they're enclosed - a loose screw terminal will overheat but tends to disconnect itself before burning down the building because its inside a box. A lot of modern kit uses sprung terminals which (sans overload) are either a good connection or no connection. The US wiring regs are written assuming fire is the primary danger. AFCIs only protect against fire caused by a bad joint. If you're not using wirenuts then AFCIs don't really do anything much. RCDs will both save your life *and* prevent fire. Definitely fit them.
This is not correct. First, wire nuts properly used are at least as effective and reliable as pressure crimps (which they are a different form of), and in any case are limited in use to connections within approved junction boxes and certain conduit bodies.
Second, the emphasis on avoiding fires results from the controlling authority for the USA's National Electrical Code being the National Fire Protection Association.
Third, the AFCI addresses the problem of zip cord extensions routed under rugs where they gradually degrade, as well as old defective wiring in inaccessible locations, and even new cable subjected to someone's poorly positioned nail.
Fourth, most AFCIs sold are combo types that include GFCI functionality.
Biting the hand that feeds IT
