Electrical fittings
Electrical fittings are devices for connecting and breaking an electric circuit. A switch connects and disconnects appliances; it has a base, a body and two contacts, one moving and one fixed. The switch contact is made of copper or brass. By structure a switch may be wall- or ceiling-mounted or hanging. A lamp holder connects a light bulb to the mains: it consists of a body, a porcelain core, centre and side contacts and contact screws. A plug connects a consumer to the mains through a socket; non-dismantlable plugs are now used more, as they are reliable and safe. Plastic and porcelain do not conduct current, so cases are made of them. Safety: do not touch plugs and sockets with wet hands; pull a plug out by the plug itself, not the cord; do not push sharp objects into a socket; replacing or repairing a switch is done only with the power off by adults.
Important: children never work with mains (socket) voltage. In this lesson: only looking, pictures and small battery models (up to 4.5 V); cutting, stripping, soldering or connecting real wires is done only by the teacher/electrician with the power off. Activity: build a simple circuit with a battery (4.5 V), a small bulb and a cardboard “switch” (paper clip); watch the bulb with the switch open/closed. Use only a battery.