IEC 61439 - The Switchgear Standard
The new standard IEC 61439 replaces the old 60439. Compared to the old standard, the new 61439 is a more clearly defined and takes into account the assembly...
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...
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...
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...
ABB Technical Guides - Motor Operation
ABB has produced a range of technical guides that offer concise explanations of the major technologies and technical issues in low voltage AC drives. ...
Generation of a Sine Wave
A fundamental concept behind the operation of alternating current systems is that voltage and current waveforms will be sinusoidal – a Sine Wave. This...
Resistors
Resistors are electronic components that oppose the flow of current. Manufactured in various types and ranges they have a wide application to electronics...
Arc Flash Calculations
Working in the vicinity of electrical equipment poses an hazard. In addition to electric shock hazard, fault currents passing through air causes Arc Flash...
Lighting - Lamps
Lamps are the essential part of any luminaire. These are the light generating components. Since the advent of electrical lighting in the middle of the...
MIT OpenCourseWare
MIT OpenCourseWare, makes the materials used in teaching all MIT subjects available on the Web, free of charge, to any user in the world.