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...

Per unit fault calculations is a method whereby system impedances and quantities are normalised across different voltage levels to a common base.  By removing...

Modelica is an open source (free) software language for modelling complex systems. Having never used it before, I thought I would download a development...

In three phase systems, the use of transformers with three windings (or legs) per side is common.  These three windings are often connected in delta or...

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...

Problems on achieving maximum voltage drop within an installation come up often. Depending where you live, local regulations will have different limits...

Many medium voltage (MV) indoor switchgear rooms  exist worldwide. The complexity of these rooms varies considerably depending on location, function and...

If two dissimilar metals are touching and an external conducting path exists, corrosion of one the metals can take place.  Moisture or other materials...

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The following tables provide quick order of magnitude fault levels for a a range of typical low voltage situations.