How to refer fault levels across a transformer
Over the past year or so I've been involved in on going discussions related to referring fault levels from the secondary of a transformer to the primary...
Cable Insulation Properties
Cable insulation is used to provide electrical separation between conductors of a cable. During the historical development of cables, numerous types...
IEC Reference Designations
The IEC publishes a series of documents and rules governing the preparation of documents, drawings and the referencing of equipment. Depending on country...
9 power supply issues solved by using a UPS
Installation of a UPS can help in reducing problems due to issues with the power supply. A lot of people relate this to nine key issues. Depending on...
Lithium Ion Battery
Over recent years the Lithium Ion battery has become popular in applications requiring high power densities with small weight and footprint. Today Lithium...
Differential protection, the good old days
This morning I was explaining how differential protection works to a junior engineer. To give him something to read I opened up the NPAG (Network Protection...
IEC 60287 Current Capacity of Cables - Rated Current
In the previous note we looked at the approach taken by the standard to the sizing of cables and illustrated this with an example. We then looked at one...
Fault Calculation - Per Unit System
Per unit fault calculations is a method whereby system impedances and quantities are normalised across different voltage levels to a common base. By removing...
Back to basics - the Watt (or kW)
When thinking about watts (W) or kilowatt (kW = 1000 W) it can be useful too keep in mind the fundamental ideas behind the unit. Watt is not a pure electrical...
Network Theory – Introduction and Review
In electrical engineering, Network Theory is the study of how to solve circuit problems. By analyzing circuits, the engineer looks to determine the various...