We are pleased to present below all posts archived in 'October 2011'. If you still can't find what you are looking for, try using the search box.
If you are working on a large plan, get the real coordinates [latitude, longitude] for two or more points and add them to the drawing. That way you can always work out the scale and dimensions.
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 1827 by Georg Ohm the law defines the re... read more..
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 spare item. If any one item of equipment breaks dow... read more..
A lot of our members work in countries where PPE (personal protective equipment) is regulated or they work for companies/organizations which take employee safety seriously. Unfortunately, there are plac... read more..
‘Kept looking at a card, y’see? Kept looking at it. Welcome back Bottle. Gods below welcome home.
read more..
This morning I was explaining how differential protection works to a junior engineer. To give him something to read I opened up the NPAG (Network Protection and Automation Guide, by Areva) and turned to... read more..
ABB has produced a range of technical guides that offer concise explanations of the major technologies and technical issues in low voltage AC drives. ...
The IEC publishes a series of documents and rules governing the preparation of documents, drawings and the referencing of equipment. Depending on country...
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...
The standard aims to consolidate AC and traction voltages within the industry and defines the following bands: band 1 - A.C. systems 100 V to 1...
I think this post is going to be helpful to several of our readers. While the IEC low voltage circuit breaker Standard [IEC 60947-2, Low voltage switchgear...
The windings of many medium and small sized transformers are protected by restricted earth fault (REF) systems. The illustration shows the principal of...
Three phase systems are derived from three separate windings, either connected in delta or star (wye). Each winding can be treated separately, leading...
Variable frequency drives are widely used to control the speed of ac motors. This note looks at the mechanisms which enable drive units to control the...
Carrying out a protection system discrimination study is critical to ensure the correct functioning of the electrical system in the event of faults. ...
It wasn't so long ago I was telling someone that I don't use rules of thumb as most things are easily calculated anyhow. As it turns out I last week...
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.