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.

Arc Flash Calculator

Calculation of arc flash incident energy and protection boundary in accordance with IEE Std. 1584 'IEEE Guide for Performing Arc-Flash Hazard Calculations'.

Sytem Details

Equipment Details

Arc Flash


Tip: registered users can save calculations.

Symbols

V - system voltage (kV)
Ibf - bolted three phase fault current (kA)
Ia - arcing current (kA)
E - incident energy (J/cm2)
EB - - incident energy at boundary distance (J/cm2)
En - - normalized incident energy (J/cm2)
t - arcing time (s)
D - distance from arc to person (mm)
CB - distance of boundary from arc point (mm)

Notes

  1. Boundary Energy can be set at 5.0 J/cm2 for bare skin or at the rating of any proposed PPE.
  2. The limit of 5.0 J/cm2 is that at which a person is likely to receive second degree burns.
  3. To convert J/cm2 to cal/cm2 multiply by 0.239
Gap and distance factors
Voltage (kV) Equipment Type Typical gap between
conductors (mm)		 Distance factor,
x
0.208 - 1



 Open Air 10-40 2.000
Switchgear 32 1.473
MCC and Panels 25 1.641
Cable 13 2.000
>1 - 5 Open Air 102 2.000
Switchgear 13-102 0.973
Cables 13 2.000
>5 -15 Open Air 13-153 2.000
Switchgear 153 0.973
Cables 13 2.000

For a more detailed explanation of the calculation, please see: Arc Flash Calculations Post

What does N+1 mean?

The term 'N+1' relates to redundancy and simply means that if you required 'N' items of equipment for something to work, you would have one additional...

Lightning Protection and Earth Electrode Resistance

Most installations involve some form of lightning protection system which is connected to an earth electrode.  The function of the earth electrode is to...

Photovoltaic (PV) Panel - Performance Modelling

In an earlier note on the site [Photovoltaic (PV) - Electrical Calculations], the theory of solar (PV) cell calculations was introduced.  In particular...

Contribute to myElectrcial

Have an opinion or something to say, want to ask or answer questions, share your knowledge then use our site to do it . As a community of people interested...

Cables for MV Power Distribution - Earthed versus Unearthed Systems

Power cables can basically be classified into earthed and unearthed cables, where earthed and unearthed refer to the application for which the cable is...

Star-Delta Motor Starting - Performance

Many questions sent in to the site are in connection with motor starting and in particular star-delta.  For all but the simplest application, there is...

IEC 61439 Verification Methods

The (relatively new) switchgear and control gear standard, IEC 61439 'Low-voltage switchgear and controlgear assemblies' has three methods which can be...

How to measure power supply quality

If your are ever called out to troubleshoot something on your electrical system, one of the first things consider is the supply voltage. You want to ensure...

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...

Capacitors - Energy Storage Application

Capacitors have numerous applications in electrical and electronic applications.  This note examines the use of capacitors to store electrical energy....

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