Report on Electricity and Lighting for Building Services Engineering

This report delves into various aspects of electricity and lighting within the context of building services engineering. It begins with an examination of uninterrupted power supplies (UPS), detailing their features, characteristics, and applications, including considerations for resilience, manageability, and maintenance. The report then moves on to safety principles when handling electrical circuits, emphasizing the importance of protective measures and proper equipment. Subsequent sections cover equipment used in domestic electrical installations, overcurrent protection devices, and cable sizing calculations. Furthermore, it explores legislation and standards for fire systems in industrial/commercial buildings, including different types of cables and fire protection systems. Finally, the report addresses lift and control panel design, focusing on installation methods and wiring circuits, including types of lift control for AC motors.

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ELECTRICITY AND LIGHTING FOR BUILDING SERVICES ENGINEERING
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Contents
2.3 Uninterrupted power supply..........................................................................................................2
Features of the uninterrupted power supply....................................................................................2
Characteristics of uninterrupted power supply.................................................................................2
Analysis of the application of the uninterrupted power supply........................................................5
3.2 safety principle when handling the electrical circuits......................................................................5
Equipment used in the domestic electrical installation.....................................................................7
3.3 overcurrent protection devices.......................................................................................................9
Specifications...................................................................................................................................11
Testing and commission..................................................................................................................12
3.4 cable size.......................................................................................................................................13
Factors to be considered when calculating cable size.....................................................................14
DOL connection...........................................................................................................................14
Star-delta starting........................................................................................................................14
Cable factors....................................................................................................................................14
4.1 legislation and standard of fire system in the industrial/commercial building..............................15
4.3 Types kinds of cable associated with fire alarm system.................................................................18
Non plenum.....................................................................................................................................19
Riser.................................................................................................................................................19
Firepower limited (plenum).............................................................................................................19
Multi-conductor (plenum)...............................................................................................................19
Mid-capacitance (plenum)...............................................................................................................19
Firepower limited (non-plenum).....................................................................................................20
Multi-conductor, non-plenum.........................................................................................................20
Mid-capacitance (non-plenum).......................................................................................................20
Multi-paired (non-plenum)..............................................................................................................20
4.4 fire protection systems..................................................................................................................21
Design fire protection systems for industrial and/or commercial buildings with fire load density..21
5.2 LIFTS AND CONTROL PANELS.........................................................................................................23
B. Design and apply appropriate methods of installation and wiring circuit...................................23
5.4 design for a lift control panel and installation requirements for a 5-story lift installation.............24
Types of lift control for AC motor....................................................................................................26
References...........................................................................................................................................28

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2.3 Uninterrupted power supply
Features of the uninterrupted power supply
 The size is compact and is ergonomically designed to allow for the placement of the
UPS on top of the desk or any strategically located environment.
 This system has a perfect system protection for the overload, short-circuiting, an
oversupply of the voltage, and an overheating of the system.
 It increases the boost and the buck AVR for the stabilization of voltage.
 It optimizes the reliability by the use of excellent microprocessors contained in the
uninterrupted power supply.
 The UPS has three modes which include Line mode, battery mode, and fault alarms
(Administration, 2009).
 It resets automatically when the AC is recovering.
 Its eco-friendly, user-friendly and frequency auto adaptive
 There is low maintenance cost due to the AVR protection function.
 The UPS has wide input range i.e. it has a large input of the voltages.
 Uninterrupted power supply system is easy to install (Barreveld, 2015)
Characteristics of uninterrupted power supply
In connection with the building management in the data center the following factor has to be
considered; resilience, manageability of the UPS, control of the bypass, maintainability and
the comparison of the output key components to the building management needs.
Resilience
This UPS is typically a reliable device but can be of great effect to the failure of the
servers connected to it. If there is virtualization of each server and multiple virtualized
machines are hosted, the disruption of the potential workload can be great. Hence any data
center must put into account the resilience factor. The selection of the UPS that can support

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numerous power inputs must be considered, this will allow the powering of the UPS unit by
two different sources. This implies that when there is a failure in one utility line then the
other shall keep the load running and also charging the uninterrupted power supply
(Brownell, 2009).
The second option is, the parallel operation supported by the Uninterrupted Power
Supply system. This will allow for greater operating time and when there is a failure in the
parallel battery then there will be power to run the UPS. Since two UPS system runs in
parallel it is known as +1 redundant. But if there is the parallel configuration of the UPS then
it is referred to as the architecture of N+1, where N is the required load supplied by the
device and +1 is the value that determines the load demand that is required when there is a
failure in one UPS. Despite this consideration, there is a recommendation of the assessment
of the device and the stability of the UPS as there are changes in the conditions of the load.
The preference in the use of parallel operation by the data center manager to aid in the scaling
up of the capacity of the UPS (Brownell, 2009).
Most of the servers have a redundant supply of power. Additional resilience can be
achieved by the use of redundant power supply due to the connection of the servers. The
management should make the connection of supply to one line and the next supply to the
Uninterrupted Power Supply.
Management and monitoring
The manageability is one of the important factors that the managers have to consider.
For the smaller installations, there should be the use of the USB and RS-232 that is known as
the serial ports. But the inclusion of the IP connection by data center UPS system should be
done to allow the management of the remote across Ethernet LAN. This mechanism also
supports the servers of the remote and the storage in the management of the system. Proper

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management system allows monitoring of the equipment in any location and alarm signals
are sent if something went wrong. This implies that critical information should be directed to
the building management system.
The distribution of the power is a responsibility of the facility personnel, hence the
integration of the building management system is equally important. When there is an alert
that there is a problem, the information must be passed to the IT expert. The typical interface
is applied to monitor and manage the UPS and the administration is also allowed to track
numerous factors such as the availability of power and the load current, running time and the
temperature of the Uninterrupted Power Supply (Bryson, 2014).
Capability of the bypass control
The working of the UPS unit is extended beyond the use of the transformer and the
basic design. This factor has the capability of allowing the UPS to be removed from the
distribution power system. This also allows the prevention of the defective UPS that causes
the outage of power which tends to prolong the downtime. This ability to bypass permits the
maintainability and the repair without load disruption.
Maintenance and the output;
This characteristic should be considered especially at the battery. The maintainability
and repair of the UPS should be easy and the technicians should use the field replaceable
batteries for the upgrade. Hot-swappable batteries in the UPS gives room for the replacement
of the damaged batteries.
Analysis of the application of the uninterrupted power supply
Uninterrupted power supply is mostly applied in the electronics devices. The applications are
of a wider range. They include

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 Power supply in computers; the current power supply in the computers have power
switch mode that aids in the conversion of the AC power to DC power voltages. This
switching supply helps in the replacement of the linear supplies as a result of
improvement of the cost, weight and the size. The variation of the current drawn is
due to the collection of the output voltage.
 Power supply for the Electric vehicle; this type of vehicle deeply rely on the created
energy from the electricity generation. Supply of the power is part of the design which
directly relates to the conversion of the power battery voltage.
 Welding power supply; this power supply provides the electricity in form of AC and
DC for the melting of metal surfaces in Arc welding. The welding arc requires high
current which ranges between 100A to 300 A. Besides, the welding power supply has
transformers that drive the generators (Bennett, 2009).
3.2 safety principle when handling the electrical circuits
I. When handling the electrical circuits always makes sure that you put on rubber gloves
and appropriate goggle.
II. When handling the electrical appliance's water should avoid data all costs and one
should never touch electrical appliance with wet hands. With the water in the hand,
there is an increase in the conduction that may lead to electrocution.
III. When doing installation one should not use the ladder made of aluminum. This can
lead to the electric surge that might lead to electrocution.
IV. When one is dealing with home appliances all the mains must be switched off to
avoid electrocution. It is also recommended that one should place some indication that
there is some work that is ongoing in that particular area (Crolla, 2015).

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V. One should never use insulators that are damaged and plugs that are broken, this will
also avoid one from electrocuting that might lead to the death of the operators and any
other user.
Safety procedures
During the installation, there are some of the safety measures that one should take into
consideration. Some of these safety measures include;
 The power should be off; during the installation, one should always do the checking
on the source of power and circuit breakers to confirm if they are off. The breakers
should be locked but in case they are not locked then everybody should be made
aware that the breakers are off and then a notice has to be placed in the area that some
electrical work is ongoing.
 Wearing of the protective cloths and protective: when one is dealing with any
electrical operation, they should put on protect fabric and parks which are long, such
as pants, gloves and also closed shoes. In cases where the electrical works are done
outdoor or they are done on a larger area, they should be wearing the hard hat and
some construction gear (Erjavec, 2003).
 Testing should be done first; wire connection should be tested before the start of any
electrical operation. The voltage tester should be used to confirm whether they are
actually dead. This creates room for the judgment of the kind of the tools to be used
and to identify the need for the work to be done.
 Should always carry the right tool; during the installation, one should always have a
proper tool for the kind of the work that one is doing. This will allow you to finish the
work as fast as possible. It is detrimental to have the right tool during installation.
Some of the tools that one needs to have are a tester used to test voltage, strippers

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used to strip wires amongst others. Some heavy machine is needed especially during
the work on large scale jobs.
 The work should be checked; after doing the work, it should be checked for a loose
connection that might set the whole area into flames. The fire caused electrically is as
a result of the electric sparks. All connections should be pulled to confirm if they are
secure. The electricity should be turned on to confirm if everything is working
correctly and the operation of the system is starting to work without incidences. The
casing of the wire should be checked by the voltage tester to confirm if there are no
leakages. For the case of longer lifespan, there should be the use of right insulators.
And all the electrical works should be done by the professionals (Owen, 2013).
Equipment used in the domestic electrical installation
Fish tape -this is used in the pulling of the solid wire through metal. There is the availability
of the lube of the cables which aids in the pulling of the wire through the pipe.
Tape measure- it is used in the measurement of the switch heights and the outlets. Also used
in centering the lighting fixture boxes
Hammer -used in securing the boxes with nails on the brackets. It can also be used in the
driving of the traps with romex especially when adding new Romex wiring.
Channels lock pliers -this is an equipment that is used in taking of the knockouts from the
boxes, down romex connectors tightening and aids in the adjustment of the ceiling fan boxes
that are expandable.
Wire strippers –this is used in the removal of the insulation from the wire. They are designed
with the different type of the teeth depending on the size of the wire that is to be cut.

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Voltmeter; this is used in checking of the variation of the voltages and aids in the verification
of the live circuits. The choice of the voltmeter should be based on the need of the user.
Non-contact voltage detector; this equipment is used for checking the presence of a flow of
current and some voltage. Since some devices switch automatically while others do not, this
device helps in checking the flow of the current before starting operation in such devices. It is
normally placed at the end of the wire to see if there is activation.
Linesman pliers; this is a device that is used in several functions. They are used in the cutting
of the wire, twisting wires together and aids in the gripping of the wires. Their ends are
squared to twist the wire towards a center cutting blade and an area between the handle used
for pulling the wire.
Torpedo level; this is used in the levelling of the work done by the installer, the installation
should be straight for proper use.
Flashlight; this is used in an area where there is less lighting and there is a need for the
installation. It helps in the improvement of the lighting in the area of work to avoid the
mistake in connection (Gordon, 2016).
Allen wrench set -This is a device that is applied in the tightening of the screws with Allen's
head during installation.
Razor blade knife; this is a device that is used in the cutting of the insulation from the wire
with Romex. It is also used in the opening of the boxes during installation.
Phillips screwdriver; this is a screwdriver that has four different blades used in the installation
of the screws with Philips' head.

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Wire crimpers; this is a tool that is used in the stripping of the wire and also in the crimping
of the lug onto the wire.
3.3 overcurrent protection devices
(a) A 11kV feeder is protected by overcurrent and earth fault protective relays fed from
600/5 CTs The phase fault relays are set at 125 % (PS), 0.4 ™; and the earth fault relay is set
at 40% 0.6. If the fault current during a single phase to earth fault is 3000A, (1) evaluate the
operating time of the relays by Normal inverse relay characteristic may be used. In addition,
(2) please produce specifications for overcurrent protection devices for testing and
commission.
Solution
Fault current = 3000A
Supply =11kV
CT ratio = 600/5
=120
Pick up current
=% PSB setting * CT secondary current
= 125% * 5
=6.25
Plug settling multiplier
= fault current / (Pick up current * CT ratio)

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=3000/ (6.25* 600/5)
=4
Form the table, the corresponding value to the PSM settling 4 = 1.5
The operation of time = 1.5
The time of operation relay
T= TMS * time corresponding to 4
=1.23 * 1.5
=1.9 seconds
b)
Overcurrent protection devices OCPD
An overcurrent is said to exist when the current that is flowing exceeds the ratings of the
conductors which are used in the supply, sometimes even the equipment. Before noting down
the specifications let’s consider some definitions
 Overload – this refers to a state whereby the conductors or the equipment carry the
amount of current which exceeds the rating of the equipment's or the conductors, for
instance, plugging a 25A electric kettle into 20A circuit branch.
 Short circuit – this refers to the accidental connection between any two conductors
which normally carry current for instance line to neutral or a line to line
 Ground fault – this term refers to an accidental fault which conducts electrically
between the equipment, enclosures of metallic nature, or the earth and an ungrounded

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conductor. In the events of a ground fault, currents and voltages that are extremely
dangerous are usually experienced (Johnson, 2012).
Circuits or equipment
Overcurrent protection devices offer protection to both the circuits and equipment but they
first provide the protection to the circuit and thereafter the equipment. It offers protection to
the circuit by breaking or opening upon the current being supplied reaching a certain limit
that may result into a temperature rise of the conductors. Usually, the devices which help in
the opening are the fuses and the circuit breakers which are normally rated at certain limits
and the rating of the interrupt must be good enough to cause the maximum possible fault
current triple off (Erjavec, 2003).
Overcurrent protection devices offer protection to the equipment by opening upon the
detection of a ground fault or a short circuit. Normally, all the electrical equipment's have
short-circuited currents which are responsible for allowing the Overcurrent protection devices
to disable the ground faults or the short circuit currents without causing any damage to the
circuit components.
Specifications
The specifications include
 Power loss hazard
In situations where the circuit protection would result in hazard, then the Overcurrent
protection devices are not required.
 Overcurrent protection devices rating must not exceed 800A