The windings of many medium and small sized transformers are protected by restricted earth fault (REF) systems. The illustration shows the principal of...

Lead acid batteries are cost effect and reliable, making them suitable for many applications.This note examines topics of interest associated with the...

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Anyone specifying or using electric motors should have a basic understanding how the insulation is related to temperature. Three classes of insulation...

Depending where in the world you work, you are likely following one of two standards International Electrotechnical Commission (IEC) National...

Within Europe the European Committee for Electrotechnical Standardization (CENELEC) has standardised the both the designation and colour of cables.   ...

The calculation of current in a three phase system has been brought up on our site feedback and is a discussion I seem to get involved in every now and...

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...

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Current transformers (CTs) are used to convert high level currents to a smaller more reasonable level for use as inputs to protection relays and metering...