Notes

3 Phase Loads 

By on

Three Phase SystemWe have had some more forum questions on this, so a quick explanation/reminder.

Three phase systems are derived from three separate windings, either connected in delta or star (wye). Each winding can be treated separately, leading to the idea that the load in each winding can be viewed independently. I'm not going into any math's, but if you did you can prove this.

 

What it means in practice is that if you know the load in each phase, the total load is the simply the sum of the individual loads. Easy to remember. By using this you can turn any three phase problem into a single phase problem which is easier to solve.

 

Some related links:

, ,

More interesting Notes:
Steven McFadyen's avatar Steven McFadyen

Steven has over twenty five years experience working on some of the largest construction projects. He has a deep technical understanding of electrical engineering and is keen to share this knowledge. About the author

myElectrical Engineering

comments powered by Disqus

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...

DC Motor Operation

Coils of wire on the rotor carry a d.c. current which generates a magnetic field. A stator magnetic field is created using either permanent magnets or...

Restricted Earth Fault Protection

The windings of many medium and small sized transformers are protected by restricted earth fault (REF) systems. The illustration shows the principal of...

Multimeter

Multimeters are undoubtedly the most common item of electrical test equipment in use.  Often it is the first piece of equipment people will turn to when...

Introduction to Lighting

When looking at the design of a lighting scheme it is useful to have an understanding on the nature of light itself and some of the basic theory associated...

Skin Tapping Input

Tapping your forearm or hand with a finger could soon be the way you interact with gadgets. A new technology created by Microsoft and Carnegie Mellon ...

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...

Electromagnetic Compatibility (EMC)

Electromagnetic compatibility (EMC) is the study of coordinating electromagnetic fields give off equipment, with the withstand (compatibility) of other...

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...

UPS Sizing - Rules of Thumb

It wasn't so long ago I was telling someone that I don't use rules of thumb as most things are easily calculated anyhow.   As it turns out I last week...

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. 

Footer
(click here to extend)
Copyright (c) 2026 myElectrical