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..
When making adding a Note to our site we have a great online WYSIWYG editor and things are pretty simple. However, if you prefer you can write, manage...
While not as popular as it once was, frame leakage protection does still have some use in some circumstances. In essence frame leakage is an earth fault...
We have a sister note to this (Robots - Interesting Video), in which I have posted some videos of interesting robots developed by commercial corporations...
IEC 61439 'Low-voltage switchgear and controlgear assemblies', specifies standard arrangements of switchboard (call forms of internal separation). The...
The term 'N+1' relates to redundancy and simply means that if you required 'N' items of equipment for something to work, you would have one additional...
Current transformers (CTs) are used to convert high level currents to a smaller more reasonable level for use as inputs to protection relays and metering...
Estimating maximum demand is a topic frequently discussed. Working out how much power to allow for a building can be very subjective . Allowing too much...
Most installations involve some form of lightning protection system which is connected to an earth electrode. The function of the earth electrode is to...
For unbalance conditions the calculation of fault currents is more complex. One method of dealing with this is symmetrical components. Using symmetrical...
Electrical engineering is a field that covers a wide variety of sub-fields, including electricity and electronics. It is a field that goes back to the...
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