Category: 1. Basic Electrical terms

In AC circuits, the power factor is the ratio of the real power that is used to do work and the apparent power that is supplied to the circuit. The power factor can get values in the range from 0 to 1. When all the power is reactive power with no real power (usually inductive load) – the power… Continue reading Power Factor

Power efficiency Power efficiency is defined as the ratio of the output power divided by the input power: η = 100% ⋅ Pout / Pin η is the efficiency in percent (%). Pin is the input power consumption in watts (W). Pout is the output power or actual work in watts (W). Example Electric motor has input power consumption of 50 watts. The motor was… Continue reading Electric Power Efficiency

What is electric charge? Electric charge generates electric field. The electric charge influence other electric charges with electric force and influenced by the other charges with the same force in the opposite direction. There are 2 types of electric charge: Positive charge (+) Positive charge has more protons than electrons (Np>Ne). Positive charge is denoted… Continue reading Electric Charge

Electric power definition The electric power P is equal to the energy consumption E divided by the consumption time t: P is the electric power in watt (W). E is the energy consumption in joule (J). t is the time in seconds (s). Example Find the electric power of an electrical circuit that consumes 120… Continue reading Electric Power

Resistance definition Resistance is an electrical quantity that measures how the device or material reduces the electric current flow through it. The resistance is measured in units of ohms (Ω). If we make an analogy to water flow in pipes, the resistance is bigger when the pipe is thinner, so the water flow is decreased. Resistance calculation The resistance… Continue reading Electrical Resistance

Electric current definition Electrical current is the flow rate of electric charge in electric field, usually in electrical circuit. Using water pipe analogy, we can visualize the electrical current as water current that flows in a pipe. The electrical current is measured in ampere (amp) unit. Electric current calculation Electrical current is measured by the rate of… Continue reading Electric Current

Electrical voltage is defined as electric potential difference between two points of an electric field. Using water pipe analogy, we can visualize the voltage as height difference that makes the water flow down. V = φ2 – φ1 V is the voltage between point 2 and 1 in volts (V). φ2 is the electric potential at point #2 in volts… Continue reading Electrical Voltage