This Calculator Is Built For You If:

Audience list:

• You are an electrical engineer or engineer-in-training sizing cables for mining, industrial, or petrochemical projects.
• You work under SANS 10142 or IEC 60364 and need your calculations to be defensible and sign-off ready.
• You are tired of cross-referencing multiple tables, applying derating factors manually, and reformatting the result into a report every time.
• You are a consultant who wants a professional, repeatable calculation workflow across all your projects.
• You are an engineer at a contractor or EPC company who needs to turn around cable sizing quickly without errors.

This is NOT for you if:

• You work only on domestic or small commercial installations where full IEC derating methodology is not required.
• You need a tool that auto-populates a full cable schedule from a load list (that is a separate, more complex product — see the Cable Sizing Masterclass course).

What the Calculator Does

Feature list:

• Current-carrying capacity check — compares your selected cable against the required current automatically.
• Voltage drop calculation — runs both running current and motor starting current scenarios simultaneously.
• Short-circuit withstand verification — checks that the selected cable survives the fault current for the given protection device clearance time.
• All six derating factors — ambient temperature, grouping, installation method, soil thermal resistivity, depth of burial, and solar radiation. Enter your values; the calculator applies them in the correct sequence.
• Cable selection guidance — the tool flags pass/fail for each check so you know immediately if the selected cable meets all criteria.
• Compliant calculation report — the output sheet is formatted for client submission and engineering sign-off. Print or export to PDF directly from Excel.
• Standards-based — built to SANS 10142-1 and IEC 60364-5-52. Suitable for South African and international projects.

What's in the file:

• 1 × Excel workbook (.xlsx) — Cable Sizing Calculator v1.1
• 1 × PDF quick-start guide — explains each input field and how to read the output report
• 1 × worked example — pre-filled with a real motor cable calculation so you can see the tool in action before entering your own data.

Digital Download Guarantee 

✓ 7-Day Satisfaction Guarantee

If the calculator doesn't work as described — wrong standard applied, formulas producing incorrect results, or the file won't open in Excel 2016 or later — email me within 7 days and I'll either fix the issue immediately or refund you in full.

Note:

Refunds are not issued for change-of-mind on digital downloads, but I will always resolve a genuine product issue.

FAQ

Does this replace the Practical Cable Sizing Masterclass?

No — the calculator is the tool; the Masterclass is the training. The Masterclass teaches you to use this calculator correctly, work through real case studies, and produce professional documentation. If you're new to cable sizing, start with the course.

What Excel version do I need?

Microsoft Excel 2016 or later on Windows or Mac. The file uses standard formulas — no macros. Google Sheets is not supported.

Will I receive updates?

Yes. All purchasers receive future v1.x updates of the calculator through their Teachable account.

Can I use this for commercial projects?

Yes. The calculator is a professional engineering tool. As with any engineering calculation, results must be reviewed, verified, and signed off by a registered professional engineer before use in a commissioned project.

What version of Excel do I need?

Excel 2016 or later on Windows. The calculator uses standard Excel functions — no macros, no VBA, no add-ins required. It will open in Excel 365 and Excel 2019/2021 without issues.

Does it work on Mac?

Yes, in Excel for Mac (2016 or later). Some formatting may differ slightly but all calculations function correctly. It is not designed for Numbers or Google Sheets.

Which standards does it cover?

SANS 10142-1 (South African) and IEC 60364-5-52 (international). The current-carrying capacity tables are from SANS 10142-1 Annex B. Voltage drop and short-circuit withstand methods follow IEC 60364.

 Can I use this for domestic installations?

Technically yes, but it is over-engineered for domestic use. For a house or small commercial building, a simpler table-lookup approach is more practical. This tool is designed for industrial and mining projects where all six derating factors are typically relevant.

What happens when v1.2 is released?

Buyers of v1.1 receive v1.2 as a free update. You will be notified by email when it is available.

Is this tool accepted by clients and engineering review panels?

The tool produces a formatted calculation report that presents the methodology clearly. It has been used on projects reviewed by major engineering firms in the mining and petrochemical sectors. Whether a specific client or certifier accepts it depends on their own requirements, but the methodology is fully standards-compliant.