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
Lightning Risk Assessment (IEC 62305)

IEC 62305 'Protection against lightning' requires a risk assessment be carried out to determine the characteristics of any lightning protection system...

ANSI (IEEE) Protective Device Numbering

The widely used United Sates standard ANSI/IEEE C37.2 'Electrical Power System Device Function Numbers, Acronyms, and Contact Designations' deals with...

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...

Cable Sheath and Armour Loss

When sizing cables, the heat generated  by losses within any sheath or armour need to be evaluated. When significant, it becomes a factor to be considered...

Maximum Demand for Buildings

Estimating maximum demand is a topic frequently discussed. Working out how much power to allow for a building can be very subjective . Allowing too much...

DC Component of Asymmetrical Faults

The image (reproduced from IEC 60909) shows a typical fault in an ac system.  From the illustration it can seen that there is an initial dc component ...

Gas Insulated or Air Insulated Switchgear

Various arguments exist around SF6 Gas Insulated (GIS) and Air Insulated (AIS) medium voltage switchgear. Recently we had to change a GIS design to AI...

Smarter Electrical Distribution

The other day I came across an article in Technology Review on the development of a smart transformer. A professor at North Carolina State University is...

myElectrical - Cable Sizing Tool Upgrade

Our IEE cable sizing was wrote a few years ago and had become rough around the edges. I thought it was time to give the tool a service. Unfortunately when...

Low Voltage Switchroom Design Guide

Low voltage (LV) switchrooms are common across all industries and one of the more common spatial requirements which need to be designed into a project...

Footer
(click here to extend)
Copyright (c) 2025 myElectrical