We are pleased to present below all posts archived in 'May 2012'. If you still can't find what you are looking for, try using the search box.
How often installations are inspected is up to the owner of the installation, provided such durations do not exceed any regulatory maximums in force. The criticality of the electrical installation to th... read more..
Laplace transforms and their inverse are a mathematical technique which allows us to solve differential equations, by primarily using algebraic methods. This simplification in the solving of equat... read more..
I have been thinking recently that there appears to be less professional integrity around than when I first started my career in electrical engineering. Recently the IET has also had a discussion around... read more..
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 are plugged in to. For larger amounts of power,... read more..
A fundamental concept behind the operation of alternating current systems is that voltage and current waveforms will be sinusoidal – a Sine Wave. This is best explained by considering how a coil of wire... read more..
Circuit breakers are switching devices whose primary function is to isolate parts of an electrical distribution system in the even of abnormal conditions. Abnormal conditions are generally caused ... read more..
In 2011, with the introduction of it’s Panda search ranking algorithms, Google introduced tools for determining the original author of posts. The intention is to provide more relevant search... read more..
From the earliest times, humans have found ways to create light. Pre-historic peoples used natural materials (moss, grass, etc.) soaked in animal fat and then ignited. Around 3000 to 4500 BC, oil lam... read more..
The International System of Units (abbreviated SI) is the world's most widely used system of units. The system consists of a set of units and prefixes. read more..
IEC 60228 is the International Electrotechnical Commission's international standard on conductors of insulated cables. Among other things, it defines a set of standard wire cross-sections. In the United... read more..
One of the requirements to ensuring that everything works is to have equipment selected, manufactured and verified [tested] to IEC standards. Not all equipment out there meets this requirements. It is t... read more..
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 are combined in a multitude of ways to produce ... read more..
A UPS is an uninterruptible power supply. It is a device which maintains a continuous supply of electrical power, even in the event of failure of the...
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...
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 European Union is implementing a voluntary code of practice for participants with the aim of improving the overall efficiency of data centres. As part...
IEC 62305 'Protection against lightning' requires a risk assessment be carried out to determine the characteristics of any lightning protection system...
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...
I was digging in my bookshelf and came across the 80th Anniversary Association of Mine Resident Engineers, Papers and Discussions Commemorative Edition...
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...
If you want to check a circuit is dead (not live), you should always use the three point method. First check a known live circuit, then check the dead...
We have a sister note to this (Robots - Interesting Video), in which I have posted some videos of interesting robots developed by commercial corporations...
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