Hazardous Areas – IEC and NEC/CEC Comparison
Depending where in the world you work, you are likely following one of two standards
International Electrotechnical Commission (IEC)
National...
Electromagnetic Fields - Exposure Limits
Exposure to time varying magnetic fields, from power frequencies to the gigahertz range can have harmful consequences. A lot of research has been conducted...
Variable Frequency Drive
Variable frequency drives are widely used to control the speed of ac motors. This note looks at the mechanisms which enable drive units to control the...
Questions - Reputation and Privilege
Our question and answer system while letting you do exactly what it says, is much more. It is a dynamic user driven system, where our users not only ask...
Capacitors - Energy Storage Application
Capacitors have numerous applications in electrical and electronic applications. This note examines the use of capacitors to store electrical energy....
Three Phase Power Simplified
A single phase system is perhaps the most common type of system most people are familiar with. This is what people have in their homes and what appliances...
How to Size Power Cable Duct
Some colleagues had an issue earlier in the week on sizing conduits to be cast in concrete for some power cables . It became clear that none of us had...
Periodic Electrical Installation Inspection – How Often?
How often installations are inspected is up to the owner of the installation, provided such durations do not exceed any regulatory maximums in force. ...
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...
How to refer fault levels across a transformer
Over the past year or so I've been involved in on going discussions related to referring fault levels from the secondary of a transformer to the primary...