Batteries
A battery consists of one or more cells, each of which use stored chemical energy to produce electrical energy, There are many types of cells and these...
RLC Circuit, Resistor Power Loss - some Modelica experiments
Modelica is an open source (free) software language for modelling complex systems. Having never used it before, I thought I would download a development...
Star-Delta Motor Starting - Performance
Many questions sent in to the site are in connection with motor starting and in particular star-delta. For all but the simplest application, there is...
Low Voltage Circuit Breakers
Circuit breakers are switching devices whose primary function is to isolate parts of an electrical distribution system in the even of abnormal conditions...
Cable Insulation Properties
Cable insulation is used to provide electrical separation between conductors of a cable. During the historical development of cables, numerous types...
How to Size Current Transformers
The correct sizing of current transformers is required to ensure satisfactory operation of measuring instruments and protection relays. Several methods...
International System of Units (SI System)
The International System of Units (abbreviated SI) is the world's most widely used system of units. The system consists of a set of units and prefixes...
HTML Symbol Entities
HTML supports a variety of entity symbols which can be entered using either numbers or an entity name. The number or name is preceded by the ‘&’ sign...
DC Component of Asymmetrical Faults
The image (reproduced from IEC 60909) shows a typical fault in an ac system. From the illustration it can seen that there is an initial dc component ...
Mobile Phones (Brick to Implant)
The mobile phone was born in 1973. They were the size of a brick and weighed a couple of kg, making them difficult to fit into your pocket. At a few thousand...