This document discusses the components and requirements for building services engineering, including reception and distribution of the main supply. It is divided into four components: control point, main switches and switchboard, branch distribution boards, and wiring. The control point should provide overcurrent protection and no break in the neutral wire. Main switches should be located near the entry point and be easily accessible. Branch distribution boards should provide spare circuits and not exceed 10 points or 800W per circuit. Wiring must be capable of carrying maximum rated current and follow specific sizing, routing, and protection methods.

1. BUILDING
SERVICES
ENGINEERING

2. RECEPTION AND DISTRIBUTION OF
MAIN SUPPLY
• Divided into four components:
• Control Point
• Main switches and switchboard
• Branch Distribution Boards
• Wiring

3. CONTROL POINT
• Should provide a circuit breaker/miniature circuit breaker/switch at the point of
entry
• Should not be a break in the neutral wire –either as a switch or fuse unit
• The Main switch should be easily accessible – easy to terminate the service line

4. MAIN SWITCHES AND
SWITCHBOARD
• Main switches should be metal clad or insulated enclosed pattern and fixed near
the point of entry
• Open switch types preferred only in dry, ventilated rooms – should not be in the
vicinity of batteries, chemical fumes, gas stoves
• Three types of Main switchboards
• Hinged type metal boards
• Fixed type metal boards
• Wood boards

5. BRANCH DISTRIBUTION BOARDS
• One spare circuit should be provided on each branch distribution board
• Lights and fans can be wired to the same circuit
• Each circuit should not have more than ten points of lights, fans, and socket outlets
– load restricted to 800watts
• Should be provided with fuse and an earthed neutral conductor

6. • Special requirements – IC switch on a separate circuit should be provided for
Air-conditioners
• Fuse boards should be easily accessible – to be replaced in case of damage
• Should be totally enclosed if exposed to weather or dampness

7. WIRING
• All conductors, switches, and accessories should be capable of carrying
maximum current according to ratings
• Conductors should be of copper or aluminum
• Min. the cross-sectional area of the conductor:
• For sub-circuit wiring – 1 mm2 for copper
• - 1.5 mm2 for aluminum
• For power wiring - >= 2.5mm2 for copper
• - >= 4 mm2 for aluminum
• If flexible cord – 0.5 mm2

8. • Power sub circuits should be different from lighting and fan subcircuits
• Wiring should be easily inspected
• Surface wiring should be nearer the ceiling and have a good and neat appearance
• Wiring when passing through walls should follow one of three methods below:

9. • Wiring should pass through a wooden box, extending the whole thickness of the
wall and is buried in the wall, and allow an air space of 1.3 cm on three sides of the
conductor or casing
• Passing in a rigid steel conduit or rigid nonmetallic conduit of accepted standards
or porcelain tube
• When passing through floors, protected by a rigid steel conduit, earthed and
secured.

10. THANK YOU