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..
Reading is a bit of a hobby of mine and I"ve done a few off-topic posts in the past on this. Rather than continue doing the occasional post I thought ...
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...
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...
A recurring theme on our forums is cable sizing. Now many installations are unique and require special consideration. However, a lot of the time things...
IEC 60228 is the International Electrotechnical Commission's international standard on conductors of insulated cables. Among other things, it defines a...
Various techniques exist to enable the correct selection of batteries for UPS applications. The procedure described below is one of the more common. ...
Lead acid batteries are cost effect and reliable, making them suitable for many applications.This note examines topics of interest associated with the...
In an earlier note on the site [Photovoltaic (PV) - Electrical Calculations], the theory of solar (PV) cell calculations was introduced. In particular...
Electrical engineering has a multitude of laws and theorems. It is fair to say the Ohm's Law is one of the more widely known; it not the most known. Developed...
In the previous note we looked at the approach taken by the standard to the sizing of cables and illustrated this with an example. We then looked at one...
If you have some expert knowledge or experience, why not consider sharing this with our community.
By writing an electrical note, you will be educating our users and at the same time promoting your expertise within the engineering community.
To get started and understand our policy, you can read our How to Write an Electrical Note.