Tools

Cable Sizing Application

Click here to register to use our cable sizing application

What Changed

So that we can focus all our efforts on our new application, we have retired our myElectrical.com cable sizing calculator. We recommend you now use our main cable sizing application over at myCableEngineering.com.

myCableEngineering.com

Cable Sizing Software - select, size and manage your power cables using myCableEngineering. All your cables, for all your projects.
  • LV and MV cables up to 33 kV with current capacity in accordance with BS 7671, ERA 69-30 and IEC 60502.
  • Positive and zero sequence impedance to IEC 60609. Voltage drop in accordance with CENELEC CLC/TR 50480.
  • Project management and team collaboration, with clear easy to read calculations and reports.

Our software is the only cloud-based solution and has been built from the ground up to be fully responsive - meaning you can access your cables from anywhere and on any device, desktop, tablet or smartphone.

Induction Motor Calculator

Calculate the synchronous speed, slip and rated torque for an induction motor


Tip: registered users can save calculations.

Symbols

  • f  -  system frequency (Hz)
  • nr  - rated (or rotor) speed (rpm)
  • ns  - synchronous speed (rpm)
  • P   - number of poles
  • Pr  - motor rated power (kW)
  • S   - motor slip (%)
  • Tr  - rated torque (Nm)

Formulae

Synchronous Speed

n s = 120f P

Rotor Slip

S= n s − n r n s ×100%

Note: for locked rotor nr = 0, therefore S = 1. The slip will decrease as the rotor speed increases.

Rated Torque

T r = 9550− P r n r
Electromechanical Relays

Electromechanical relays have been the traditional backbone of electrical protection systems.  While over recent years these have been replaced by microprocessor...

Windows Live Writer and myElectrical

When making adding a Note to our site we have a great online WYSIWYG editor and things are pretty simple.  However, if you prefer you can write, manage...

8 Motor parts and common faults

Straight forward list of some common motor faults.  If I have missed any other common faults, please take a bit of time to add them in as a comment below...

Write your best report

Years ago I was told that you should always try to write the best report you can.  Many years later I still think on this as one of the better pieces of...

Motor Starting - Introduction

Motor starting and its associated problems are well-known to many people who have worked on large industrial processes. However, these things are, of course...

Differential protection, the good old days

This morning I was explaining how differential protection works to a junior engineer. To give him something to read I opened up the NPAG (Network Protection...

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...

IEC 60287 Current Capacity of Cables - An Introduction

IEC 60287 "Calculation of the continuous current rating of cables (100% load factor)" is the International Standard which defines the procedures and equations...

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...

Calculating Cable Fault Ratings

When selecting a cable, the performance of the cable under fault conditions is an important consideration. It is important that calculations be carried...

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