Cable Size Calculator
– CABLE SIZING SOFTWARE –
Don’t get caught short, have the cable calculator app to hand ready for when you need it.
Do you ever need to carry out a quick on-site cable size calculation? If so, this is where this cable calculator becomes handy, a pocket sized cable calculator app for your mobile device.
Calculate the minimum cable size for various cable types, protective devices, installation methods and correction factors, also calculates voltage drop, R1+R2 and Ze, based on British Standard 7671.
- Calculate a cable size in two easy steps with instant results!
CABLE CALCULATION FEATURES
- Cable Size Calculation
- Maximum Zs
- Voltage Drop Calculation
- Tabulated Current (It)
- Expected Zs
- Print or Save The Results
- Expected R1+R2
- Digitally Sign & Approve
Don’t take our word for it – here’s what other cable calc app users say:
Been using it for about a month now and it’s been brilliant. Best cable calc I’ve found by far.
By far the best I have used.
Great app. Best cable calculator out there.
Great fast calculating tool, very accurate.
Cable Size Calculations
CALCULATING CABLE SIZES
Carry out instant cable calculations, great for electrical surveys, condition reports, circuit design and cable sizing on the go.
This cable size calculator has been designed to make it as easy as possible, calculate a cable size in two simple steps.
Input your circuit design parameters,
- Design Current
- Length of Circuit
- Supply Voltage
- Source Ze or Zdb
Select your design options,
- Voltage Drop %
- Earthing Type
- Protective Device Type
- Device Rating
- Cable Type
- Max Disconnection Time
CABLE CALCULATION CORRECTION FACTORS
In step 2 we apply and relevant correction factors. For BS 3036 fuses a correction factor is automatically applied if a BS 3036 protective device is selected.
Select from the available options,
- Installation Method
- Ambient Temperature
- Surrounded by Thermal Insulation
Now hit the calculate button to display the results.
– Cg : Grouping
– Ca : Ambient air temperature
– Ca : Ambient ground temperature
– Ci : Thermal insulation
– Cc : BS 3036 semi-enclosed fuses
The cable calculation results screen displays your circuit design data, selected options, cable size and other related calculation results.
Cable Size Calculator Calculations:
- It : Tabulated current
- R1+R2 : Circuit expected R1+R2 value
- Zs : Circuit expected Zs value
- Max Zs : Calculated max Zs values for 0.2s, 0.4s & 5s (80% + 100% values)
- Vd : Calculated voltage drop %
- CF : Total applied correction factor value
- Minimum required cable size (mm²)
QUICK AND EASY CABLE CALCS
Calculating cable sizes need not be daunting, let the cable calc app do it for you.
✔ Print cable calculator results
✔ Verification and validation checks
✔ Support for manufacturer specific MCCB’s & ACB’s (max Zs)
✔ Support for RCD’s in TT Earthing Systems
- Quick and easy
- Saves time
- Print the results
- Digitally sign
FREQUENTLY ASKED QUESTIONS
What are correction factors?
Correction factors are multipliers applied to cable sizing calculations for specific circumstances.
Correction factors include:
- Cg Grouping
- Ca Ambient air temperature
- Ca Ambient ground temperature
- Ci Thermal insulation
- Cc BS 3036 semi-enclosed fuses
What is Zdb?
Zdb is the term generally used to refer to the earth loop impedance at a distribution board.
What is design current?
The circuit design current is the minimum amount of current the circuit needs to be able to sustain in normal use.
To calculate the design current or maximum demand check out our Diversity / Maximum Demand Calculator App.
What is Voltage drop?
Voltage drop is the amount of volts lost due to the resistance of a cable, the longer the cable is the higher the volt drop will be.
This is also true for varying cable sizes, the smaller the cable the higher the voltage drop will be, hence for long circuits a larger cable might be required to satisfy the maximum permitted voltage drop.
Demo video may show an older version of the app
Tablets and Phones
OPTIMISED FOR MULTIPLE SCREEN SIZES
This cable calculation software is optimised to work on all screen sizes and resolutions from the iPhone 5 up to large tablets such as the iPad Pro and all Android devices.
- Easy to use
- Print results
- Quick and instant results
- Dedicated support team
DOWNLOAD YOUR CABLE CALC APP TODAY!
Volt Drop Calculation
VOLTAGE DROP CALCULATOR
This cable calculator will also calculate and apply a voltage drop calculation as part of the cable sizing calculation process. Volt drop is generally measured in mV (millivolts) or as a percent (%), A millivolt is one thousandth of a volt.
If a cable calculation fails the Volt drop maximum but passes all other requirements such as Max Zs, Current Carrying Capacity etc. then you will be prompted with a message “Volt Drop Compliance Failed, try next cable size up?” to select the next larger cable size to then try the full calculation again until all of the requirements are met before selecting the most suitable cable size.
If you only need to carry out a Voltage Drop Calculation and not a Cable Size Calculation you can use our free Voltage Drop Calculator.
Cable Size for Cooker
COOKER CABLE SIZES
The cable size for a cooker is dependent on multiple factors, these factors include kW rating of the cooker, the method of installation used for the installation of the cooker cable, the length of the cooker cable and the rating of the required over-current protection device.
Things to consider when selecting a suitable cable size for a cooker is the max Zs of the over-current protective device, voltage drop, cable rating and the manufactures instructions.
The maximum current carrying capacity (rating) of a cooker cable can be significantly reduced depending on the installation method used to install the cable (see the relevant current carrying capacity tables for cables in BS 7671), correction factors may also be relevant and need to be applied.
Cooker Connection Cable
When connecting a cooker, oven or electric hob to the cooker connection unit (CCU) outlet, the cable selected for this purpose should comply with the manufactures installation instructions, many manufactures specify a suitably sized H07 cable (similar to what can be found here H07RN-F) is used and NOT a standard flat twin and earth cable, a flat twin & earth cooker cable does not support the heat resistant properties which many manufactures specify for connecting directly to a cooker, oven or electric hob. See this Doncaster Cables spec sheet for a H07RN-F cable datasheet.
Beware when purchasing a suitable cable for anything be that a cooker, hob, oven or anything else, ALWAYS only use approved cables purchased from a reputable supplier, believe it or not there are fake cables on the market.
You can use this cable calc app for calculating the cable size for a cooker.
Current Carrying Capacity for SWA
SWA CURRENT CARRYING CAPACITY
The current carrying capacity tables for some SWA cables is already pre-programmed in to this cable calc app.
To view the current carrying capacity of SWA cable tables you can find them in Appendix 4 Current-Carrying Capacity and Voltage Drop for Cables of BS 7671. We have also included a few of those Current Carrying Capacity tables in our Electricians App “Electrical Tools and Reference”.
Demo video may show an older version of the app
CABLE SIZE CALCULATION SOFTWARE
Calculate cable sizes for a variety of different cable types and installation methods.
- Simple to use & print the results
- Calculate Volt Drop
- Calculate Estimated Zs and R1+R2
- Calculate Cable Size