3 Phase Loads
Three phase systems are derived from three separate windings, either connected in delta or star (wye). Each winding can be treated separately, leading...
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...
Photovoltaic (PV) - Utility Power Grid Interface
Photovoltaic (PV) systems are typically more efficient when connected in parallel with a main power gird. During periods when the PV system generates energy...
Voltage Levels – Confused?
I was having a conversation the other day about voltage levels. While everyone was in agreement that low voltage was 1000 V and less, there was more confusion...
Cable Sizing Software
When sizing cables nearly, everyone uses some form of software. This ranges from homespun spreadsheets to complex network analyses software. Each has its...
Understanding LV Circuit Breaker Fault Ratings
I think this post is going to be helpful to several of our readers. While the IEC low voltage circuit breaker Standard [IEC 60947-2, Low voltage switchgear...
Cost Performance and Time
Often us engineers get so bogged down in equations, using software, producing drawings and writing specifications that this becomes the sole focus. ...
Fault Calculation - Symmetrical Components
For unbalance conditions the calculation of fault currents is more complex. One method of dealing with this is symmetrical components. Using symmetrical...
Random Numbers
Using laser optical pulses the random number generator utilizes the time between arrival of random photos to generate the numbers, ensuring true accuracy...
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...