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ELEK Cable Pro Web™

Compliant with NEC (NFPA 70) Standards

Electrical Design and Wire Sizing Software

*No credit card required - ongoing free plan.

What is Cable Pro Web?

ELEK Cable Pro Web is cloud-based electrical design software for electricians, electrical engineers and contractors in the United States.

Design NEC (NFPA 70) compliant electrical systems with tools for wire sizing, service load calculations, voltage drop analysis, grounding conductor sizing, protection coordination, arc flash analysis and standards-referenced reports.

Get your free account and run compliant electrical calculations from any device.

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Key Features and Capabilities

Electrical System Design

Automated low-voltage electrical system design from utility service or transformer supply through multiple switchboards, loads and capacitor banks.

Generate calculation reports, equipment schedules and single-line diagrams for your electrical system designs.

  • Interactive Single-Line Diagrams: Build and visualize custom network diagrams with live editing and AutoCAD® export.
  • Service, Transformer & Generator Sizing: Size utility services, transformers and generators while designing systems with multiple switchboards and panelboards.

  • Fault Current Verification: Verify conductor sizing and protective device settings using calculated fault current values.

  • Fault Current & Service Load Calculations: Calculate available fault current and upstream load requirements for switchboards, panelboards, and distribution equipment.

Protective Device Coordination and Selection

Perform coordination studies, verify selective coordination and choose the right protective devices with confidence.

  • Time-current curves: Plot time-current curves and verify selective coordination between circuit breakers and fuses.

  • Huge database of devices: Over 50,000 manufacturer devices. Time-current curves, settings, breaking capacities, part numbers and characteristics are available.

  • Coordination Criteria & Sequence of Operation: Verify current-based and time-based selective coordination in accordance with project requirements.

  • Generate Commissioning-Ready Reports: Create detailed reports including time-current curves showing selective coordination, device details and protective device settings.

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Wire Sizing and Service Load Calculations

Easily determine the minimum compliant conductor size in accordance with NEC (NFPA 70) Standards.

The service load calculator automatically applies the rules for all installation types and balances the loads.

  • Automatic Conductor & Grounding Conductor Sizing: Automatically determine minimum compliant conductor and grounding conductor sizes, or manually select conductors to verify compliance.

  • Voltage Drop Analysis: Calculate voltage drop and voltage rise for DC, single-phase and three-phase electrical systems.

  • Automated Service Load Calculations: Automatically calculates residential and commercial load requirements in accordance with NEC demand factors and installation rules.

  • Ground Fault Current Verification: Verify conductor sizing and protective device selection using calculated ground fault current values.

Compliance Reports and Project Documentation

Create client-ready reports, compliance documentation and wire schedules directly from your electrical design calculations.

  • Custom-Branded PDF Reports: Generate professional reports containing calculation inputs, results and compliance checks, complete with your company logo.

  • Standards-Based References: Includes referenced NEC (NFPA 70) tables and supporting standards data to improve transparency and verification.

  • Voltage Drop Reports: Generate dedicated voltage drop reports for multiple conductor runs and support project documentation requirements.

  • Wire Schedules for Project Delivery: Export wire schedules directly to Excel for procurement, construction documentation and project handover.

AI Electrical Calculations

Get standards-compliant cable sizing results through ChatGPT and Claude’s interfaces, backed by the proven Cable Pro Web engine.

  • Natural Language Workflow: Describe your project requirements conversationally without entering parameters manually.
  • Verified Calculations: Every calculation is produced by the Cable Pro Web engine, delivering results you can trust on real projects.
  • Standards-Compliant Results: Receive outputs aligned with NEC (NFPA 70) requirements, complete with documented calculation details.

  • Submission-Ready Reports: Generate professional reports with applied parameters, referenced standards and traceable results.
Diagram showing Cable Pro Web (CPW) cable sizing calculator engine connecting to Claude and ChatGPT, indicating compatibility with both AI platforms.

Start For Free Today

Our Free Plan never expires and no credit card is required. With no software to install, you’re minutes away from easy and accurate calculations.

Explore the NEC (NFPA 70) compliant features:

You’re viewing United States cable sizing calculations in Cable Pro Web using NEC (NFPA 70).

Need another standard? Select one below.

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United States

NEC (NFPA 70)

Current Standard

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Australian & NZ

AS/NZS 3008

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British

BS 7671

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International

IEC 60364-5-52

A Plan for Every Need

Select from a range of plans. Not ready to decide? Simply choose our Free plan – no credit card required.

Discounts are available for additional users and for annual payments. Prices shown are inclusive of tax.

Annual Plans (Save 45%)
Monthly Plans

Free

0
Per year, per seatThe number of seats translates to how many users can access Cable Pro Web at the same time.

No credit card required

100 cable sizing calls per day

Main Features:

Online Documentation & Tutorials

No Commitment

Works on Desktop and Mobile

Essential

81
Per year, per seatThe number of seats translates to how many users can access Cable Pro Web at the same time.

50% discount on additional seats

500 cable sizing calls per day

Main Features:

Cable Sizing Includes:

Auto-size or manual. 1ph, 3ph, DC, 2ph. Cu/flex, Al/flex conductors. Accurate voltage drop/rise. Fault loop impedance check. Derating factors. Protective devices. Conduit sizing. Short-circuit rating. Unbalanced voltage drop (Premium plan or above). Reports with references.

Live Chat with Engineering Support

No Contracts, Cancel Anytime

Works on Desktop and Mobile

Premium

239
Per year, per seatThe number of seats translates to how many users can access Cable Pro Web at the same time.

50% discount on additional seats

1500 cable sizing calls per day

Main Features:

Maximum demand Includes:

Domestic or living units and non-domestic installations. Automatically applies rules and balances phases.

Live Chat with Engineering Support

No Contracts, Cancel Anytime

Works on Desktop and Mobile

Professional

515
Per year, per seatThe number of seats translates to how many users can access Cable Pro Web at the same time.

50% discount on additional seats

5000 cable sizing calls per day

Main Features:

LV Network Calculator Includes:

Electrical network calculations with multiple switchboards, Single line diagrams, Transformers and generators, Fault level calculations, Protection coordination, Arc flash, Power factor correction, AutoCAD design export.

Live Chat with Engineering Support

No Contracts, Cancel Anytime

Works on Desktop and Mobile

Start For Free Today

Our Free Plan never expires and no credit card is required. With no software to install, you’re minutes away from easy and accurate calculations.

Frequently Asked Questions

Yes, ELEK Cable Pro Web includes a dedicated version built specifically for the United States, and performs electrical design and wire sizing calculations in accordance with NEC (NFPA 70).

ELEK Cable Pro Web supports several international standards in the same software, selected at login:

  1. Australian and New Zealand Standard: AS/NZS 3008 and AS/NZS 3000.

  2. British Standard: BS 7671.

  3. International Standard: IEC 60364.

  4. United States Standard: NEC (NFPA 70) 

Yes, you can get started in two ways:

  1. Free account: Requires no credit card and gives you immediate access to basic wire sizing calculations. 

  2. Free 14-day trial: For engineers and electricians who want to evaluate the full feature set of our paid plans: Essential, Premium and Professional.

You can access ELEK Cable Pro Web on any device (desktop, laptop, tablet, or mobile) with an internet connection and a web browser.

ELEK Cable Pro Web is fully responsive and adapts to any device screen, including desktop, tablet, and mobile devices. Simply log in from any device, anywhere, via your web browser.

Multiple users can share a login; however, only one user can be logged in at a time. If you’d like to share an account, then you can create a generic username, for example, “YourCompanyName”. Contact us if you’d like assistance to do this.

You will be automatically logged out of your office computer so you can use the software immediately on your mobile.

Yes, your calculations and projects are securely stored in the cloud and are linked to your private account. Storage limits depend on your subscription plan. Each plan includes a specific amount of cloud storage, and you can upgrade at any time to increase capacity. You can also archive your projects and calculations as needed.

ELEK Cable Pro Web is supported by a team of electrical engineers who understand the work you are doing. Support is available via live chat directly inside the application on paid plans, and by email for all users.

The ChatGPT and Claude AI interface doesn’t do the calculation; the ELEK Cable Pro Web engine does.

The AI handles the conversation; every number is generated by the same deterministic calculation engine that ELEK Cable Pro Web users rely on. Results in chat are identical to results in ELEK Cable Pro Web, verified field-by-field.

Yes, ELEK Cable Pro Web is suitable for residential electrical installations and performs wire able sizing calculations in accordance with the NEC (NFPA 70). Single-phase loads are automatically balanced across phases and included in all compliance calculations and reports, helping ensure accurate and code-compliant residential electrical designs.

Yes, ELEK Cable Pro Web is suitable for commercial and industrial electrical installations and performs wire sizing calculations in accordance with the NEC (NFPA 70). The software supports complex electrical systems with multiple switchboards, large loads and detailed calculation reports, making it suitable for projects ranging from small commercial developments to large industrial facilities.

Expert Support and Resources

Our software is designed to be simple and intuitive, but if you need a helping hand, we have a support team and range of online resources to help get you get up to speed quickly.

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First Class Support

Our technical team is on-hand to assist you with any questions you have about ELEK software.

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Step-by-Step Tutorials

Dive into our library of tutorials to expand your skills and get more from Cable Pro Web.

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Technical Resources

Broaden your knowledge with our range of videos and in-depth articles on a wide range of topics.

Start For Free Today

Our Free Plan never expires and no credit card is required. With no software to install, you’re minutes away from easy and accurate calculations.

elek about team - Electrical Design & Wire Sizing Software | NEC (NFPA 70)

About ELEK Software

We're Here For You

ELEK is an electrical software company founded in 2009.

We provide software solutions to the electrical design industry. Our vision is to provide the world’s best and most innovative electrical software for engineers and electrical contractors.

Our software is developed and supported by an experienced team from our head office.

Read about our story.