Photovoltaic (PV) - Utility Power Grid Interface

By Steven McFadyen on 4/4/2013 12:47 PM

Photovoltaic (PV) systems are typically more efficient when connected in parallel with a main power gird. During periods when the PV system generates energy this can be utilized and the grid energy u... read more..


Switchboard - Forms of Internal Separation

By Steven McFadyen on 1/29/2012 12:57 PM

IEC 61439 'Low-voltage switchgear and controlgear assemblies', specifies standard arrangements of switchboard (call forms of internal separation).

read more..


Fire Resistant and Fire Retardant Cables

By Steven McFadyen on 7/4/2013 1:31 PM

Fire resistant and fire retardant cable sheaths are design to resist combustion and limit the propagation of flames. Low smokes cables have a sheath designed to limit the amount of smoke and toxic ha... read more..


How to measure power supply quality

By Steven McFadyen on 2/14/2012 11:43 AM

If your are ever called out to troubleshoot something on your electrical system, one of the first things consider is the supply voltage. You want to ensure you have a good electrical supply before movin... read more..


IEC Document Designation

By Steven McFadyen on 5/9/2012 2:07 PM

Often document control is dictated by project requirements, for example a particular organisation may have an existing numbering system. Existing company or group/department document control systems may... read more..


Lighting Design - An Introduction

By Steven McFadyen on 4/12/2012 1:50 PM

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 then ignited. Around 3000 to 4500 BC, oil lam... read more..


Low Voltage Circuit Breakers

By Steven McFadyen on 4/15/2012 1:55 PM

Circuit breakers are switching devices whose primary function is to isolate parts of an electrical distribution system in the even of abnormal conditions.  Abnormal conditions are generally caused ... read more..


Medium Voltage Switchgear Room Design Guide

By Steven McFadyen on 5/9/2012 2:12 PM

Many medium voltage (MV) indoor switchgear rooms  exist worldwide. The complexity of these rooms varies considerably depending on location, function and technology adopted by the owner. This articl... read more..


Low Voltage Switchroom Design Guide

By Steven McFadyen on 5/9/2012 2:10 PM

Low voltage (LV) switchrooms are common across all industries and one of the more common spatial requirements which need to be designed into a project. Main LV switchrooms w... read more..


Standard Cable & Wire Sizes

By Steven McFadyen on 4/9/2012 7:45 AM

IEC 60228 is the International Electrotechnical Commission's international standard on conductors of insulated cables. Among other things, it defines a set of standard wire cross-sections. In the United... read more..


Power Factor

By Steven McFadyen on 7/10/2012 11:43 AM

Power factor is the ratio between the real power (P in kW) and apparent power (S in kVA) drawn by an electrical load.

The reactive power (Q in kVAr) causes the real and apparent power to be ... read more..


Introduction to Lighting

By Steven McFadyen on 4/4/2012 1:32 PM

When looking at the design of a lighting scheme it is useful to have an understanding on the nature of light itself and some of the basic theory associated with this.  This article provides an over... read more..




How to refer fault levels across a transformer

Over the past year or so I've been involved in on going discussions related to referring fault levels from the secondary of a transformer to the primary...

MIT OpenCourseWare

MIT OpenCourseWare, makes the materials used in teaching all MIT subjects available on the Web, free of charge, to any user in the world.

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...

IEC Reference Designations

The IEC publishes a series of documents and rules governing the preparation of documents, drawings and the referencing of equipment.   Depending on country...

Robots - Interesting Videos

The robot folding towels post below was interesting enough at the time to post a link.  Recently I’ve come across a couple of other interesting videos...

Lithium Ion Battery

Over recent years the Lithium Ion battery has become popular in applications requiring high power densities with small weight and footprint.  Today Lithium...

Surface Treatment – Ladders, Trays and Baskets

Steel ladders, trays and baskets form the backbone of cable containment systems. Often these items need some form of surface treatment to prevent corrosion...

Fault Calculation - Per Unit System

Per unit fault calculations is a method whereby system impedances and quantities are normalised across different voltage levels to a common base.  By removing...

Understanding Motor Duty Rating

One of the comments on my Motor Starting Series was asking for something on duty cycles. Here it is. As a purchaser of a motor, you have responsibility...

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...

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