Introduction to Lighting
When looking at the design of a lighting scheme it is useful to have an understanding on the nature of light itself and some of the basic theory associated...
Multimeter
Multimeters are undoubtedly the most common item of electrical test equipment in use. Often it is the first piece of equipment people will turn to when...
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...
Smarter Electrical Distribution
The other day I came across an article in Technology Review on the development of a smart transformer. A professor at North Carolina State University is...
Photovoltaic (PV) Panel - Performance Modelling
In an earlier note on the site [Photovoltaic (PV) - Electrical Calculations], the theory of solar (PV) cell calculations was introduced. In particular...
Lead us, Warleader
Delum, who had watched all in silence, his face empty of expression, now spoke in turn. ' "Lead us, Warleader, into glory."'
Reading is something I do...
DC Motor Operation
Coils of wire on the rotor carry a d.c. current which generates a magnetic field. A stator magnetic field is created using either permanent magnets or...
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...
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...
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...