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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...

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...

Resistors are electronic components that oppose the flow of current.  Manufactured in various types and ranges they have a wide application to electronics...

For unbalance conditions the calculation of fault currents is more complex. One method of dealing with this is symmetrical components. Using symmetrical...

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...

When current flows within a wire, a magnetic field is created. The potion of this magnetic field perpendicular to the wire is called the magnetic flux...

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...

A UPS is an uninterruptible power supply.  It is a device which maintains a continuous supply of electrical power, even in the event of failure of the...

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...