Three phase system
Introduction
The three-phase system is an economical way of bulk power transmission over long distances and for distribution. The three-phase system consists of a three-phase voltage source connected to a three-phase load by means of transformers and transmission lines. Two types of connections are possible, namely delta (Δ) connection and star or wye (Y) connection. The load and the source can be either in delta or star. The transmission line will be in delta connection. Normally the power system is operated in balanced three-phase condition. Most of the bulk loads such as industrial loads are three-phase balanced loads in nature. However, when there is a mix of single-phase and three-phase loads such as residential loads, the load will be unbalanced. Nevertheless, an unbalanced load can be resolved into a set of more than one balanced system. Hence, the analysis of a balanced system at steady state will be enough to understand three-phase systems
Three-phase power is a three-wire ac power circuit with each phase ac signal 120 electrical degrees apart. Residential homes are usually served by a single-phase power supply, while commercial and industrial facilities usually use a three-phase supply.
- Trainer: Johannes Shagama
This unit standard specifies the competencies required to provide basic first aid. This includes identifying an emergency situation; applying first aid procedures and/or techniques; reporting on casualty’s condition, treatment and hand over to EMS; and reporting to record. This unit describes the competency skills and knowledge required to recognize and responds to any sudden illness, injuries and or life threatening incidents in low – risk areas.
- Trainer: Ottilie Angala