Operational Amplifier

The fundamental component of any analogue computer is the operational amplifier, or op amp. An operational amplifier (often called an op-amp,) is a high...

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...

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...

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...

Cable Insulation Properties

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

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...

Introduction to Traction Substations

Following on from my post on railway electrification voltages, I thought an introduction to traction substations would be a good idea. Traction substations...

Photovoltaic (PV) - Electrical Calculations

Photovoltaic (PV) cells (sometimes called solar cells) convert solar energy into electrical energy.  Every year more and more PV systems are installed...

Harmonised Cable Codes and Colours

Within Europe the European Committee for Electrotechnical Standardization (CENELEC) has standardised the both the designation and colour of cables.   ...

Fire Resistant and Fire Retardant Cables

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...

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