Lighting Design - An Introduction
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...
Understanding Circuit Breaker Markings
IEC 60947 is the circuit breaker standard and covers the marking of breakers in detail. Any manufacturer following this standard should comply with the...
Battery Sizing
This article gives an introduction to IEEE 485 method for the selection and calculation of battery capacity.
Periodic Electrical Installation Inspection – What to Inspect?
This is the second post in a series of two on periodic electrical inspections. In the first post, I discussed how often inspections should be carried out...
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...
Magicians of Engineering
The other day I was reading 'Night of the New Magicians' by Mary Pope Osborn with my son. The story is about a young boy and girl who travel back in time...
Batteries
A battery consists of one or more cells, each of which use stored chemical energy to produce electrical energy, There are many types of cells and these...
Photovoltaic (PV) Panel - Performance Modelling
In an earlier note on the site [Photovoltaic (PV) - Electrical Calculations], the theory of solar (PV) cell calculations was introduced. In particular...
Understanding electric motor insulation & temperature
Anyone specifying or using electric motors should have a basic understanding how the insulation is related to temperature. Three classes of insulation...
Generator Sizing & Operation Limits
When selecting a generator, there are inherent limits on the active and reactive power which can be delivered. Generators are normally sized for a certain...