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...
Battery Cars A to Z
Battery powered cars are a hot topic and widely debated. The pros, cons, issues and time frames can be talked about endlessly. An article by the Telegraph...
The ac resistance of conductors
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...
Low Voltage Fault Tables
The following tables provide quick order of magnitude fault levels for a a range of typical low voltage situations.
Why use catalogues
I'm a fan of using manufacturers catalogues. There are two main reasons for this. Firstly, if your involved in the purchase of equipment, you will likely...
How to Size Current Transformers
The correct sizing of current transformers is required to ensure satisfactory operation of measuring instruments and protection relays. Several methods...
Maxwell's Equations - Introduction
Maxwell's Equations are a set of fundamental relationships, which govern how electric and magnetic fields interact. The equations explain how these fields...
The dc resistance of conductors
This is the first of two posts on the resistance of conductors. In the next post I will look at the ac resistance, including skin effect and we deal with...
E-Ink
Before the technical, some general information. E-ink display are found in a lot of e-readers, some mobile phones and similar devices and the intent is...
Hazardous Areas – IEC and NEC/CEC Comparison
Depending where in the world you work, you are likely following one of two standards
International Electrotechnical Commission (IEC)
National...