Following on from my post on railway electrification voltages, I thought an introduction to traction substations would be a good idea. Traction substations...

Induction motors are frequently used in both industrial and domestic applications.  Within the induction motor, an electrical current in the rotor is induced...

Our cable sizing tool is one of the more popular tools on the site.  The tool enables cables to be sized in compliance with BS 7671 (the IEE Wiring Regulations...

Often document control is dictated by project requirements, for example a particular organisation may have an existing numbering system. Existing company...

For unbalance conditions the calculation of fault currents is more complex. One method of dealing with this is symmetrical components. Using symmetrical...

Electric motors are one of the most widely used items of electrical equipment. Improving motor efficiency benefits include, reduced power demand, lower...

Visitors who like to type web address rather then click menus may be interested in how our URL structure works.

The correct sizing of current transformers is required to ensure satisfactory operation of measuring instruments and protection relays. Several methods...

Per unit fault calculations is a method whereby system impedances and quantities are normalised across different voltage levels to a common base.  By removing...

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...