Harmonic and capacitor selection

Effects of Harmonics

Schneider Capacitor

Harmonics in electrical installation

The presence of harmonics in electrical systems means that current and voltage are distorted and deviate from sinusoidal wave forms.

Harmonic currents are currents circulating in the networks and which frequency is an integer multiple of the supply frequency.

Power Factor Correction

Improving the PF can maximize current-carrying capacity, improve voltage to equipment, reduce power losses, and lower electric bills. The simplest way to improve power factor is to add PF correction capacitors to the electrical system. PF correction capacitors act as reactive current generators. They help offset the non-working power used by inductive loads, thereby improving the power factor. The interaction between PF capacitors and specialized equipment, such as variable speed drives, requires a well-designed system.

Power Factor

Loads in electrical distributer systems are inductive Loads which need a magnetic field to operate, Such as motors, transformers, ballasts and furnace.

In first we should know what is the two kinds of power that be needed in the inductive loads;

UNITS OF ELECTRICAL MEASUREMENT

System Internationale (SI) Metric System

Electrical units of measurement are based on the International (metric) System, also known as the SI System. Units of electrical measurement include the following:

Ampere

Volt

Ohm

Siemens

Watt

Henry

Farad

ELECTRICAL TERMINOLOGY

Knowledge of key electrical terminology is necessary to fully understand principles in electrical science.

Method of producing electricity

As we explain in the previous topics , the electricity is produced by extraction of electrons from atoms . The energies that are used to produce an electricity are ;

Current Types

• There are Two Types of electrical Flow ;

1- Direct Current ( DC)
2- Alternating Current ( AC)

What is electricity?

On the Principle any thing consists of  a very small part which is called atom . Atom are made up of three small parts :