Notes

Electric Motors

By Steven McFadyen on 3/28/2012 1:12 PM

Collection of links to various places with useful motor information. I’ll try and return to the page every now and again to update it with any motor notes added to the site. read more..

How a Digital Substation Works

By Steven McFadyen on 3/2/2014 12:06 PM

Traditionally substations have used circuit breakers, current transformers (CT), voltage transformers (VT) and protection relays all wired together using copper cables. With advances in digital... read more..

The ac resistance of conductors

By Steven McFadyen on 1/11/2012 4:03 PM

In a previous article I looked at the dc resistance of conductors and in this article we turn our attention to ac resistance. If you have not read the previous article, now may be a good time to do so. ... read more..

Restricted Earth Fault Protection

By Steven McFadyen on 3/25/2012 12:49 PM

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

Cable Insulation Properties

By Steven McFadyen on 5/15/2012 6:13 AM

Cable insulation is used to provide electrical separation between conductors of a cable. During the historical development of cables, numerous types of insulation have been employed. ... read more..

Photovoltaic (PV) Panel - Performance Modelling

By Steven McFadyen on 1/8/2015 3:55 AM

In an earlier note on the site [Photovoltaic (PV) - Electrical Calculations], the theory of solar (PV) ... read more..

Load Flow Study – how they work

By Steven McFadyen on 12/8/2014 10:25 AM

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 the electrical network. Carrying out a load flow s... read more..

Thermoplastic and Thermosetting Insulation

By Steven McFadyen on 7/6/2011 3:12 AM

While there are a vast array of cable insulation materials, these are often divided into two general types; Thermoplastic or Thermosetting. For example the current capacity determination of a cable in a... read more..

Arc Flash Calculations

By Steven McFadyen on 3/22/2012 6:14 AM

Working in the vicinity of electrical equipment poses an hazard. In addition to electric shock hazard, fault currents passing through air causes Arc Flash. To protect people a risk analysis on the ar... read more..

Motor Starting - Introduction

By Steven McFadyen on 8/11/2011 1:28 AM

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, less familiar to others. This post ... read more..

Tips for a better Low Voltage Protection Discrimination Study

By Steven McFadyen on 11/3/2014 11:48 AM

Carrying out a protection system discrimination study is critical to ensure the correct functioning of the electrical system in the event of faults. The IEC defines discrimination as:

What is an Open Delta Transformer

By Steven McFadyen on 10/13/2014 11:54 AM

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 star, resulting in common transformer conf... read more..

Pages: Prev 123 4 5 6 7...16 Next Return Top

Induction Motor Calculator

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...

Control Theory

Control theory looks at how systems work and are controlled from a mathematical view. This note gives a brief introduction to some of the concepts – more...

Post Authorship

In 2011, with the introduction of it’s Panda search ranking algorithms, Google introduced tools for determining the original author of posts. The intention...

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. ...

What is an Open Delta Transformer

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...

UPS Battery Sizing

Various techniques exist to enable the correct selection of batteries for UPS applications. The procedure described below is one of the more common. ...

Gas Insulated or Air Insulated Switchgear

Various arguments exist around SF6 Gas Insulated (GIS) and Air Insulated (AIS) medium voltage switchgear. Recently we had to change a GIS design to AI...

Why is electricity so hard to understand?

It's been a busy few months on different projects or busy couple of decades depending on how I look at it. I can say that on the odd (frequent) occasion...

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...

What happened to the cable notes?

If you are wondering what happened to our cable notes, the short answer is that we have moved them to myCableEngineering.com. The "Knowledge Base" at...

Have some knowledge to share

If you have some expert knowledge or experience, why not consider sharing this with our community.

By writing an electrical note, you will be educating our users and at the same time promoting your expertise within the engineering community.

To get started and understand our policy, you can read our How to Write an Electrical Note.

Click here to view the notes list in a table format

Click here to view the notes indexed by tag

Popular Tags

Have some knowledge to share