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...
Variable Frequency Drive
Variable frequency drives are widely used to control the speed of ac motors. This note looks at the mechanisms which enable drive units to control the...
8 Motor parts and common faults
Straight forward list of some common motor faults. If I have missed any other common faults, please take a bit of time to add them in as a comment below...
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...
Lighting Design - An Introduction
From the earliest times, humans have found ways to create light. Pre-historic peoples used natural materials (moss, grass, etc.) soaked in animal fat and...
Load Flow Study – how they work
A load flow study is the analysis of an electrical network carried out by an electrical engineer. The purpose is to understand how power flows around...
Standard Cable & Wire Sizes
IEC 60228 is the International Electrotechnical Commission's international standard on conductors of insulated cables. Among other things, it defines a...
Paternoster Lifts
These lifts were first built in 1884 by J. E. Hall and called a paternoster ("Our Father", the first two words of the Lord's Prayer in Latin) due to its...
Medium Voltage Switchgear Room Design Guide
Many medium voltage (MV) indoor switchgear rooms exist worldwide. The complexity of these rooms varies considerably depending on location, function and...
Star-Delta Motor Starting - Performance
Many questions sent in to the site are in connection with motor starting and in particular star-delta. For all but the simplest application, there is...