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.

Duct Size Calculator


Tip: registered users can save calculations.

Typical Cable Diameters

Following outside diameters are for reference only and will vary depending on cable manufacturer. 

600/1000V XLPE Armoured

Overall Diameter (mm)
mm2 1core  2 core  3 core  4 core 
1.5    12.3  12.8  13.5
2.5    13.6  14.1  15.0
4    14.7  15.3  16.4
6    16.9  16.6  18.7
10    18.0  19.5  21.1
16     20.0  21.2  22.9
25    24.1  26.7  28.9
35    27.9  29.6  32.1
50*   17.5  25.8  28.5  32.0
70   20.2  29.0  32.2  37.7
95   22.3  33.1  37.0  41.7
120   24.2  36.1  40.0  47.7
150   27.4  39.3  45.5  51.4
185  30.0  44.7  49.8  56.6
 240  32.8  49.0  55.1  63.0
300  35.6  53.5  60.2  68.8
400  40.4  59.0  66.6  78.1
500  44.2      
630  48.8      
800  55.4      
1000  60.6      

 * - change in class of conductor

Calculation

1. Required fill factor k (in decimal)
2. Cable diameter d, giving a cable area, a:

a= π 4 d 2
3. Cable total area Ca = sum of area for all cables
4. Minimum duct diameter D:

D= 4 C a πk
Power Transformers - An Introduction

One of the fundamental requirements of an alternating current distribution systems it to have the ability to change the magnitude of voltages.  It is more...

Variable Frequency Drive

Variable frequency drives are widely used to control the speed of ac motors.  This note looks at the mechanisms which enable drive units to control the...

Why is electricity so hard to understand?

It's been a busy few months on different projects or busy couple of decades depending on how I look at it. I can say that on the odd (frequent) occasion...

Multimeter

Multimeters are undoubtedly the most common item of electrical test equipment in use.  Often it is the first piece of equipment people will turn to when...

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...

Paths of Flight

GE have put together a time-lapse video shown flight take-off and landings at some airports. An interesting view:

Motor Efficiency Classification

Electric motors are one of the most widely used items of electrical equipment. Improving motor efficiency benefits include, reduced power demand, lower...

Large Hadron Collider

The 27 km, Euro 6 billion  Collider lies on the border between France and Switzerland, took nearly 30 years to complete.  Some of the lofty goals for the...

Dielectric loss in cables

Dielectrics (insulating materials for example) when subjected to a varying electric field, will have some energy loss.   The varying electric field causes...

Power Factor

Power factor is the ratio between the real power (P in kW) and apparent power (S in kVA) drawn by an electrical load. The reactive power (Q in kVAr)...

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