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HVACR214 – Electrical for Oil

Lesson 1 Basic Electricity

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Electronics

• Will be a part of your every day job.• 90% of the problems you encounter will be

electrical.• You will not understand anything else if you

do not understand basic electrical.

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What is electricity?

• Electricity is a fundamental element of nature.

• Electricity starts with an atom consisting of an electron and a proton.

• The electrons jump from atom to atom.

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What is electricity?

• This movement of electrons creates electric current.

• With the use of a proper conductor the current will move in a controlled manner and become usable.

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What is electronics?

• Electronics is a study of the movement of electricity through wires, switches, and loads.

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Conductors

• Conductors are substances like wire, metal, earth, and water where electrical current can easily pass.

• Keep in mind that the human body is a great conductor of electricity.

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Insulators

• Insulators are substances such as rubber, cloth, dry wood, and glass that resists the flow of electricity.

• Insulators are found on the top of power poles and around wires.

• Insulators are there for safety and to isolate electrical wires.

• Most insulation you will deal with will be rubber or plastic.

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Electrical Production

• Electricity is produced by one of four methods.– Friction creates static electricity.– Chemically is how electricity is produced in a

battery.– Magnetism is how electricity is produced in a

power plant.– Mechanically is how electricity is produced in a

thermocouple.

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Electro-magnetic Force

• An electro-magnetic force is one that is created by a magnet spinning inside wires. The current that is generated by the spinning magnet is sent out over the wires to do work. This is power, voltage, and amperage.

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Voltage

• Voltage is the potential for electricity to do work.

• Voltage is measured in volts.

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Current

• Current is the movement of electrons.• Current is measured and recorded in Amps.

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Resistance

• Resistance is a force that opposes electrical flow.

• If there where to be no resistance than the current would run uncontrolled and would become what is known as a “short” circuit.

• Resistance is measured in Ohms.

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Wattage

• Watts are the measurement of power.• A watt equals one amp of current flowing

with a pressure (or potential) of one volt.• Watts are used by the power companies to

bill customers.

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Types of current

• There are two types of current– Alternating Current– Direct Current

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Direct Current

• Known as “DC”.• Direct current is what is produced by

batteries. It is what is used in automotive.• Direct current is used inside high tech

electrical devices.• Direct current is used in a lot of higher end

(more expensive) control devices.

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Alternating Current

• Alternating current is known as “AC”• Alternating current is what is available from

the power company.• Alternating current has a wave pattern to

the voltage levels that vary between positive and negative.

• In the United States this change happens 60 times per second.

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Alternating Current

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Frequency

• Frequency is the measurement of the AC voltage shifts from positive to negative.

• Frequency is measured in Hertz (of Hz)• This is usually based on times per second.• United States = 60 Hz• Europe = 50 Hz

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Line Voltage

• Line voltage is the power coming in from the power company.

• Line voltage is high voltage and in most cases can cause you serious harm, if not death.

• Line voltage is available from wall plugs.

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Control Voltage

• In most cases control voltage is lower voltage.

• Control voltage in the heating air conditioning industry is 24 VAC.

• VAC is Volts AC (or Alternating Current Voltage)

• Control voltage is designed to be easy to handle and safer.