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

Bows and Arrows

It starts with me reading one of the Horrible History books with my son (Groovy Greeks). Arrows were mentioned which lead to the discussion of the bodkin...

The dc resistance of conductors

This is the first of two posts on the resistance of conductors. In the next post I will look at the ac resistance, including skin effect and we deal with...

How to refer fault levels across a transformer

Over the past year or so I've been involved in on going discussions related to referring fault levels from the secondary of a transformer to the primary...

GE's Shingijutsu Factory

GE's latest thinking on product manufacturing is he Shingijutsu philosophy or Lean production system. They have started applying this at the Louisville...

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...

How to Size Power Cable Duct

Some colleagues had an issue earlier in the week on sizing conduits to be cast in concrete for some power cables . It became clear that none of us had...

Fault Calculations - Typical Equipment Parameters

A frequent problem in fault calculations is the obtaining of equipment parameters.  While it is always preferable to use the actual parameters of the equipment...

Periodic Electrical Installation Inspection – How Often?

How often installations are inspected is up to the owner of the installation, provided such durations do not exceed any regulatory maximums in force. ...

Understanding electric motor insulation & temperature

Anyone specifying or using electric motors should have a basic understanding how the insulation is related to temperature. Three classes of insulation...

How to Size Current Transformers

The correct sizing of current transformers is required to ensure satisfactory operation of measuring instruments and protection relays. Several methods...

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