Standard Cable & Wire Sizes
IEC 60228 is the International Electrotechnical Commission's international standard on conductors of insulated cables. Among other things, it defines a...
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...
What is an Open Delta Transformer
In three phase systems, the use of transformers with three windings (or legs) per side is common. These three windings are often connected in delta or...
Equipment Verification (to IEC Standards)
One of the requirements to ensuring that everything works is to have equipment selected, manufactured and verified [tested] to IEC standards. Not all equipment...
Medium Voltage Switchgear Room Design Guide
Many medium voltage (MV) indoor switchgear rooms exist worldwide. The complexity of these rooms varies considerably depending on location, function and...
UPS Battery Sizing
Various techniques exist to enable the correct selection of batteries for UPS applications. The procedure described below is one of the more common. ...
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...
Cable Insulation Properties
Cable insulation is used to provide electrical separation between conductors of a cable. During the historical development of cables, numerous types...
DC Component of Asymmetrical Faults
The image (reproduced from IEC 60909) shows a typical fault in an ac system. From the illustration it can seen that there is an initial dc component ...
RLC Circuit, Resistor Power Loss - some Modelica experiments
Modelica is an open source (free) software language for modelling complex systems. Having never used it before, I thought I would download a development...