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The correct sizing of current transformers is required to ensure satisfactory operation of measuring instruments and protection relays. Several methods...

This post is quick introduction and overview to different railway electrification voltages used in answer to a question sent in via email. While there...

Just added a page to the tools, which will allow you to calculate the synchronous speed, slip and rated torque for an induction motor. Not a particularly...

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...

The mobile phone was born in 1973. They were the size of a brick and weighed a couple of kg, making them difficult to fit into your pocket. At a few thousand...

The International System of Units (abbreviated SI) is the world's most widely used system of units.  The system consists of a set of units and prefixes...

The inventor of the first visible light-emitting diode makes history again this year as it begins to show customers a 40-watt replacement GE Energy Smart...

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...

This article gives an introduction to IEEE 485 method for the selection and calculation of battery capacity.