From the monthly archives: August 2009

We are pleased to present below all posts archived in 'August 2009'. If you still can't find what you are looking for, try using the search box.

IEC 61439 - The Switchgear Standard

By Steven McFadyen on 7/1/2009 3:08 AM

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 of pre-tested designs. .

Some key... read more..




Equipment Verification (to IEC Standards)

One of the requirements to ensuring that everything works is to have equipment selected, manufactured and verified [tested] to IEC standards. Not all equipment...

What is Aircraft Ground Power

Ever wondered what kind of power an aircraft uses when parked at the airport stand. Normally the aircraft generates it own power, but when parked with...

Calculating Cable Fault Ratings

When selecting a cable, the performance of the cable under fault conditions is an important consideration. It is important that calculations be carried...

RLC Circuit, Resistor Power Loss - some Modelica experiments

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

IEC 61439 Verification Methods

The (relatively new) switchgear and control gear standard, IEC 61439 'Low-voltage switchgear and controlgear assemblies' has three methods which can be...

Lithium Ion Battery

Over recent years the Lithium Ion battery has become popular in applications requiring high power densities with small weight and footprint.  Today Lithium...

Operational Amplifier

The fundamental component of any analogue computer is the operational amplifier, or op amp. An operational amplifier (often called an op-amp,) is a high...

Are We Losing Professional Integrity

I have been thinking recently that there appears to be less professional integrity around than when I first started my career in electrical engineering...

Wiki Depreciation

We have had the Wiki with us for a long time now, but at last I have decided to say bye bye – more details on why below.

ANSI (IEEE) Protective Device Numbering

The widely used United Sates standard ANSI/IEEE C37.2 'Electrical Power System Device Function Numbers, Acronyms, and Contact Designations' deals with...

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