UTILE NOTES (Basic Electricity).pdf

UTILE1 303 - INTRO AND BASIC ○ Wastewater ELECTRICITY ○ Vacuum In a SHOPPING MALL, they would BUILDING UTILITIES - Building Utilities be: means “cover...

UTILE1 303 - INTRO AND BASIC ○ Wastewater ELECTRICITY ○ Vacuum In a SHOPPING MALL, they would BUILDING UTILITIES - Building Utilities be: means “covered equipment” permanently ○ Electricity mounted on or in a building and used to ○ Water provide any of the following services within ○ Wastewater removal the building: heating, ventilating, air ○ Telecommunications conditioning, electrical power, hot water, elevator or escalator services, central Why there is a need for Civil Engineers to vacuum, natural gas service or study Basic Electricity? communications. I can identify at least one reason why a civil engineer would need to have DIFFERENCE BETWEEN BUILDING basic electrical knowledge and identify SERVICES AND UTILITIES: electrical symbols and that is when they Building services refer to the select structural framing that need to be systems and equipment within a solid he makes sure that the electrical building that provide heating, devices and components are not installed in ventilation, air conditioning, lighting, a manner that will compromise the integrity power, and other services necessary of the structural members, systems or for the building's occupants. This subsystems. Also that the structural framing can include things like elevators, has adequate backing for mounting such escalators, and fire safety system. electrical components. Utilities, on the other hand, refer to - Civil engineers often work on the external services and projects that involve the design, infrastructure that a building relies construction, and maintenance of on, such as electricity, gas, water, infrastructure such as buildings, and sewer. These utilities are roads, bridges, and other structures. typically provided by public or private - These projects often require companies and are essential for the electrical systems such as lighting, functioning of a building. In power distribution and control summary, building services are the systems. internal systems and equipment - By studying the fundamentals of within a building that provide comfort electrical engineering, civil engineers and safety for the occupants, while gain a deeper understanding of how utilities are the external services that these systems work and how to the building relies on for its basic design and integrate them into their functioning. projects. Additionally, an In a REFINERY - for example - understanding of electrical Utilities would be: engineering can enhance the energy ○ Electricity efficiency and sustainability of civil ○ Compressed air engineering projects. ○ Steam ○ Potable water ELECTRICITY - Electricity has a very large influence on our lives, but Symbol is I it is not well understood by many Unit is ampere(A) equivalent to the people. Electricity is used to power flow of 6,250,000,000,000,000,000 many of the things that we use every electrons per second day. The instrument used to measure Electric Charges - Three particles current is known as the ammeter. that make up an atom: 1 A= 1000mA= Protons - positively charged 1,000,000µA Neutrons - no charge Electrons - negatively charged VOLTAGE ○ The proton and It is the force that makes neutron are found in electrons move in a certain the center of the direction within a conductor. atom, a place called Also known as the the nucleus. Electromotive Force(EMF) ○ The electrons orbit Can be DC or AC direct and alternating current the nucleus Symbol is E or V Unit is volts(V) Voltage generated is directly proportional to the speed of rotation. V increases as speed(RPM) is increased. Voltage generated will also increase as the number of turns is increased. V increases as N is increased. Conductors and Insulators: Conductors are the materials STATIC ELECTRICITY or substances which allow Lightning is one of the most dramatic electricity to flow through example of static electricity. During a storm, them. the wind turbulence causes air to move up Insulators are the materials and down quickly. This movement of air is or substances which resist or just what is needed to cause a charge don’t allow the current to flow separation in the clouds and on the ground. through them. The top of the cloud becomes positively Semi-conductors are charged, as does the ground. The bottom of materials that posses the the cloud becomes negatively charged. The properties of both the figure below depicts the charging that conductor and the insulator. occurs during a storm. CURRENT SOURCES OF DYNAMIC ELECTRICITY The flow of free electrons on a 1. Mechanical closed electric circuit. 2. Chemical  3. Photovoltaic SOLAR OR PHOTOVOLTAIC MEANS 4. Thermoelectric Conversion of solar energy to electrical 5. Piezoelectric energy. MECHANICAL MEANS THERMAL MEANS Conversion of mechanical energy to Conversion of heat energy to electrical energy electrical energy. ICE ENGINES(Diesel, gasoline, Common applications in bunker, etc.) instrumentation and controls. Coal plants Devices are responsible in Nuclear automation of systems. Geothermal Two dissimilar metals when heated Hydro will produce electricity. Ex.: Thermocouple Faraday’s Discovery RESISTANCE “ Moving a conductor across The opposition to the flow of electrical magnetic lines of force will produce current. Measured in ohms is a term that voltage at the ends of the describes the forces that oppose the flow of conductor.” electrical current in a conductor. Unit is ohms Ω EMF Equation For DC Generator: Symbol 1K Ω = 1000Ω The EMF generated per conductor in a DC 1M Ω =1,000,000Ω generator is: The instrument used to measure resistance EMF equation for DC generator is the ohmmeter. OHM’S LAW In 1926, George Simon Ohm described the relationship between current, voltage and resistance with his popular Ohm’s Law. Z = number of conductors Ohm’s Law states that P = number of Poles “Current(I) is directly N = Speed of rotor in RPM proportional to the amount of Voltage(V) A = number of parallel paths and inversely proportional to the value of Resistance(R).” CHEMICAL MEANS Movement of electrons from one electrode to the other placed in a solution known as an electrolyte.Conversion of chemical energy to electrical energy. Ex. Batteries POWER The amount of energy transferred or converted per unit time. In the International System of Units, the unit of power is the watt. 1 HORSEPOWER= 746 WATTS 1 KILOWATT= 1000 WATTS FORMULAS FOR POWER ENERGY Energy= Power x Time Units: Energy = KW x HOURS 1 KW-HOUR = 1000 WATT-HOURS We are buying energy from CENECO since they sell their services in KW-Hrs.