How to Size Power Cable Duct
Some colleagues had an issue earlier in the week on sizing conduits to be cast in concrete for some power cables . It became clear that none of us had...
Motor Efficiency Classification
Electric motors are one of the most widely used items of electrical equipment. Improving motor efficiency benefits include, reduced power demand, lower...
Three Phase Current - Simple Calculation
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...
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...
Lead us, Warleader
Delum, who had watched all in silence, his face empty of expression, now spoke in turn. ' "Lead us, Warleader, into glory."'
Reading is something I do...
Motor Starting - Introduction
Motor starting and its associated problems are well-known to many people who have worked on large industrial processes. However, these things are, of course...
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...
Battery Sizing
This article gives an introduction to IEEE 485 method for the selection and calculation of battery capacity.
Lightning Protection and Earth Electrode Resistance
Most installations involve some form of lightning protection system which is connected to an earth electrode. The function of the earth electrode is to...
ABB Technical Guides - Motor Operation
ABB has produced a range of technical guides that offer concise explanations of the major technologies and technical issues in low voltage AC drives. ...