We are pleased to present below all posts archived in 'November 2011'. If you still can't find what you are looking for, try using the search box.
Some colleagues had an issue earlier in the week on sizing conduits to be cast in concrete for some power cables . It became clear that none of us had a clear idea on an approved method. In the end w... read more..
Request to look at induction motor starting time have come up a few times on the site. Hopefully in this post, I give you guys some idea on how to calculate this. Failing that, hopefully at least som... read more..
A quick post in connection with an email question:
Live Tank - the circuit breaker the switching unit is located in an insulator bushing which is live at line voltage (or some voltage above g... read more..
The correct sizing of current transformers is required to ensure satisfactory operation of measuring instruments and protection relays. Several methods exist to size current transformers. This note will... read more..
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 circuit and finally recheck the live circuit. Carry... read more..
Tapping your forearm or hand with a finger could soon be the way you interact with gadgets. A new technology created by Microsoft and Carnegie Mellon ...
Problems on achieving maximum voltage drop within an installation come up often. Depending where you live, local regulations will have different limits...
Over the past year or so I've been involved in on going discussions related to referring fault levels from the secondary of a transformer to the primary...
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...
IEC 60228 is the International Electrotechnical Commission's international standard on conductors of insulated cables. Among other things, it defines a...
Per unit fault calculations is a method whereby system impedances and quantities are normalised across different voltage levels to a common base. By removing...
Anyone specifying or using electric motors should have a basic understanding how the insulation is related to temperature. Three classes of insulation...
Our cable sizing tool is one of the more popular tools on the site. The tool enables cables to be sized in compliance with BS 7671 (the IEE Wiring Regulations...
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...
This post is quick introduction and overview to different railway electrification voltages used in answer to a question sent in via email. While there...
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