Nikola Tesla
Nikola Tesla was born exactly at midnight on July 10, 1856 in the tiny village of Smiljan, Lika in Croatia. In his late teens, Tesla left the village to...
Photovoltaic (PV) - Electrical Calculations
Photovoltaic (PV) cells (sometimes called solar cells) convert solar energy into electrical energy. Every year more and more PV systems are installed...
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...
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...
UPS - Uninterruptible Power Supply
A UPS is an uninterruptible power supply. It is a device which maintains a continuous supply of electrical power, even in the event of failure of the...
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...
ANSI (IEEE) Protective Device Numbering
The widely used United Sates standard ANSI/IEEE C37.2 'Electrical Power System Device Function Numbers, Acronyms, and Contact Designations' deals with...
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...
Paths of Flight
GE have put together a time-lapse video shown flight take-off and landings at some airports. An interesting view:
Frame Leakage Protection
While not as popular as it once was, frame leakage protection does still have some use in some circumstances. In essence frame leakage is an earth fault...