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 cable sizing calculator. We recommend you now use our main cable sizing application over at

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.

Motor Starting Time Calculator

Calculate the approximate starting time for asynchronous motors. Please review the notes towards the bottom of the page to understand the implications.

Motor Details

Mechanical Load Details

Tip: registered users can save calculations.

This Cacluation

The calculation uses the simplified method given in our site post 'How to Calculate Motor Starting Time' to determine the approximate starting time.


per unit voltage: this setting allows for reduced voltage starting scenarios.  For for direct online starting the motor would be operated at full voltage (per unit voltage =1).  For star-delta the voltage during starting would be 1/√3 of the normal running voltage  (per unit voltage = 0.577).  Similar situation for other starting methods. 

Introduction to Traction Substations

Following on from my post on railway electrification voltages, I thought an introduction to traction substations would be a good idea. Traction substations...

Introduction to Current Transformers

Current transformers (CTs) are used to convert high level currents to a smaller more reasonable level for use as inputs to protection relays and metering...

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...

How Electrical Circuits Work

If you have no idea how electrical circuits work, or what people mean then they talk about volts and amps, hopefully I can shed a bit light.  I’m intending...


When current flows within a wire, a magnetic field is created. The potion of this magnetic field perpendicular to the wire is called the magnetic flux...

Sony Pocket eBook Reader

For the past few years I have reading eBooks on my HTC touch phone. On and off I have debated buying an eReader and recently purchased a Sony PRS-300 ...

Maxwell's Equations - Gauss's Electric Field Law

Gauss's Electrical law defines the relation between charge ("Positive" & "Negative") and electric field.  The law was initially formulated by Carl Friedrich...

Laplace Transform

Laplace transforms and their inverse are a mathematical technique which allows us to solve differential equations, by primarily using algebraic methods...

Closed Doors

"I can live with doubt and uncertainty and not knowing. I think it is much more interesting to live not knowing than to have answers that might be wrong...

Introduction to Cathodic Protection

If two dissimilar metals are touching and an external conducting path exists, corrosion of one the metals can take place.  Moisture or other materials...