How to Install Electrical Switches

In construction of house or building, electric work also needs proper attention at the time of laying pipes, wiring and fixing various fittings including their quality and specifications. All electric fittings such as ceiling rose, wall sockets, switches, regulators and accessories are attached to wall or ceiling. Brass screws shall be used for attaching fittings to their base blokes.
 
Switches and Sockets: 

Main Switches:

• All main switches should be of the ironclad type manufactured by reputed manufacturer.
• All switches and circuit breakers shall be constructed and installed in accordance with latest guidelines from the I.E.E. Regulations.
• Handles of switches should be fastened properly, leaving no tendency to unscrew and become loose.
• All tumbler switches must be of bakelite.
• In earthed system, all single-pole switches on 2-wire circuits controlling lights, fans etc must be inserted in outer or phase wire as the case may be.
• In insulated D.C. systems, such switches are to be inserted in the positive side.
• All unlinked single-pole switches throughout an installation shall be fitted in the conductors or connected to the outer or phase conductors of the supply, or in two way system of supply, in the same conductor, which shall not be a conductor earthed either with or without a circuit breaker or added resistance in the earth connection.
• In no case shall the consumer insert any single pole switch, cut out or permit such switch, or cut out to be or remain inserted in any earthed neutral conductor.
• A fuse or unlinked single pole switch shall not be inserted in:
• The middle or neutral conductor of a three-conductor circuit supplied from a direct current or single- phase-three-wire system.
• The common return of a two-phase three-conductor circuit.
• The neutral of a three-phase four-conductor circuit.
• That conductor of an installation, which is permanently earthed at the source of supply without a circuit breaker or added resistance in the earth connection.

Installation of Main Switches:
In the installation of main switches, main and branch distribution boards the following requirements shall be full filled:

• A small bracket for pilot lamp shall be fixed and connected through an independent single pole switch.
• Connections shall be arranged as far as possible to form their own diagram.
• Each circuit shall be clearly numbered, from left to right.
• Iron clad switches and distribution boards shall be mounted on 2”x2”x1/4” angle iron frame covered with 1/8” thick iron sheet covering or in recessed cast iron boxes.
• The casing shall be connected with the main switches and distribution board through flexible metal pipes.

Wall Sockets: