Electromagnetic Fields - Exposure Limits
Exposure to time varying magnetic fields, from power frequencies to the gigahertz range can have harmful consequences. A lot of research has been conducted...
Tip – Latitude and Longitude on Large Scale Plans
If you are working on a large plan, get the real coordinates [latitude, longitude] for two or more points and add them to the drawing. That way you can...
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...
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 Sizing
This article gives an introduction to IEEE 485 method for the selection and calculation of battery capacity.
HTML Symbol Entities
HTML supports a variety of entity symbols which can be entered using either numbers or an entity name. The number or name is preceded by the ‘&’ sign...
Aluminium Windings - Dry Type Transformers
The other day I was talking to a colleague who is a building services consultant. Despite regularly specifying dry-type/cast resin transformers he was...
Voltage Levels to IEC 60038
The standard aims to consolidate AC and traction voltages within the industry and defines the following bands:
band 1 - A.C. systems 100 V to 1...
IEC 60287 Current Capacity of Cables - Rated Current
In the previous note we looked at the approach taken by the standard to the sizing of cables and illustrated this with an example. We then looked at one...
Arc Flash Calculations
Working in the vicinity of electrical equipment poses an hazard. In addition to electric shock hazard, fault currents passing through air causes Arc Flash...