How a Digital Substation Works
Traditionally substations have used circuit breakers, current transformers (CT), voltage transformers (VT) and protection relays all wired together using...
Earth Electrode Resistance
Earthing of electrical systems is essential for the correct functioning and the protecting of life and equipment in the event of faults. The earth electrode...
What is Aircraft Ground Power
Ever wondered what kind of power an aircraft uses when parked at the airport stand. Normally the aircraft generates it own power, but when parked with...
E-Ink
Before the technical, some general information. E-ink display are found in a lot of e-readers, some mobile phones and similar devices and the intent is...
Cost Performance and Time
Often us engineers get so bogged down in equations, using software, producing drawings and writing specifications that this becomes the sole focus. ...
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...
The dc resistance of conductors
This is the first of two posts on the resistance of conductors. In the next post I will look at the ac resistance, including skin effect and we deal with...
Voltage Levels to IEC 60038
The standard aims to consolidate AC and traction voltages within the industry and defines the following bands:
band 1 - A.C. systems 100 V to 1...
Understanding electric motor insulation & temperature
Anyone specifying or using electric motors should have a basic understanding how the insulation is related to temperature. Three classes of insulation...
Calculating Cable Fault Ratings
When selecting a cable, the performance of the cable under fault conditions is an important consideration. It is important that calculations be carried...