## 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

${n}_{s}=\frac{120f}{P}$

Rotor Slip

$S=\frac{{n}_{s}-{n}_{r}}{{n}_{s}}×100%$

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

Rated Torque

${T}_{r}=\frac{9550-{P}_{r}}{{n}_{r}}$

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