We are pleased to present below all posts archived in 'April 2012'. If you still can't find what you are looking for, try using the search box.
Control theory looks at how systems work and are controlled from a mathematical view. This note gives a brief introduction to some of the concepts – more of a notepad of concepts really, whi... read more..
Sometimes it’s useful to be able to quickly lookup a piece of technical information. This note is a collection of information related to motors, and in particular ac induction motors. read more..
Variable frequency drives are widely used to control the speed of ac motors. This note looks at the mechanisms which enable d... read more..
Electric motors are one of the most widely used items of electrical equipment. Improving motor efficiency benefits include, reduced power demand, lower operating costs and reduced environment impact.... read more..
Collection of links to various places with useful motor information. I’ll try and return to the page every now and again to update it with any motor notes added to the site. read more..
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 functions and its practical applicatio... read more..
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 mag... read more..
We have had the Wiki with us for a long time now, but at last I have decided to say bye bye – more details on why below. read more..
The windings of many medium and small sized transformers are protected by restricted earth fault (REF) systems. The illustration shows the principal of REF protection. read more..
Electrical notes are a collaborative collection of electrical engineering information and educational material. Any registered user can add content.
Think of Notes as an online book;&#... read more..
The widely used United Sates standard ANSI/IEEE C37.2 'Electrical Power System Device Function Numbers, Acronyms, and Contact Designations' deals with protective device function numbering and acronyms. ... read more..
Here’s list of some famous scientists. Deliberately short, with the aim to provide a quick memory jog or overview. If your looking for more detailed information, Google and Wikipedia have tons of ... read more..
Many questions sent in to the site are in connection with motor starting and in particular star-delta. For all but the simplest application, there is...
Recently I have seen a few interesting articles on viable cold fusion; the combining of atoms at room like temperatures to create boundless energy. Now...
At the beginning of the year China put the world's first 1,000 kV UHV transmission system into operation. Transmitting power at over a million volts is...
In electrical engineering, Network Theory is the study of how to solve circuit problems. By analyzing circuits, the engineer looks to determine the various...
I'm a fan of using manufacturers catalogues. There are two main reasons for this. Firstly, if your involved in the purchase of equipment, you will likely...
Photovoltaic (PV) systems are typically more efficient when connected in parallel with a main power gird. During periods when the PV system generates energy...
The 27 km, Euro 6 billion Collider lies on the border between France and Switzerland, took nearly 30 years to complete. Some of the lofty goals for the...
The fundamental component of any analogue computer is the operational amplifier, or op amp. An operational amplifier (often called an op-amp,) is a high...
There are a lot of interesting two page type notes on various medium voltage topics – switchgear, circuit breakers, bus systems etc. It is on the Siemens...
The mobile phone was born in 1973. They were the size of a brick and weighed a couple of kg, making them difficult to fit into your pocket. At a few thousand...
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