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...
Always Use PPE
A lot of our members work in countries where PPE (personal protective equipment) is regulated or they work for companies/organizations which take employee...
110 or 230 Volts
I've been considering a blog on the 110 or 230 Volt issue for a while. While browsing the Internet I came across a great summary by Borat over at engineering...
How D.C. to A.C. Inverters Work
Traditionally generation of electricity has involved rotating machines to produce alternating sinusoidal voltage and current (a.c. systems). With the development...
Motor Insulation
Insulation on a motor prevents interconnection of windings and the winding to earth. When looking at motors, it is important to understand how the insulation...
Understanding Circuit Breaker Markings
IEC 60947 is the circuit breaker standard and covers the marking of breakers in detail. Any manufacturer following this standard should comply with the...
Occam's Razor
I was reminded of Occam's Razor while reading a book. It's quite a simple principal of logic which has stood the test of time and is accepted as central...
IEC 61439 Verification Methods
The (relatively new) switchgear and control gear standard, IEC 61439 'Low-voltage switchgear and controlgear assemblies' has three methods which can be...
Gas Insulated or Air Insulated Switchgear
Various arguments exist around SF6 Gas Insulated (GIS) and Air Insulated (AIS) medium voltage switchgear. Recently we had to change a GIS design to AI...
Power Factor
Power factor is the ratio between the real power (P in kW) and apparent power (S in kVA) drawn by an electrical load. The reactive power (Q in kVAr)...