How to Become a Freelance Automation Engineer: Skills, Clients and the Business Basics

To become a freelance automation engineer you need three things before your first client: enough site experience to commission a system on your own, a reliable way to find work (usually system integrators and machine builders who need extra hands), and the business basics: a written scope, insurance, licensed software and safe working.

Are you ready to be a freelance automation engineer?

A freelancer is hired to be useful from the first morning, often on a plant that is running, with nobody available to explain the code. That changes what a client looks for. Before going independent, most engineers have:

• commissioned several complete projects, from factory acceptance test (FAT) through site acceptance test (SAT) to handover;
• found faults under time pressure on someone else's program, not only their own;
• worked on more than one version of their main platform, because clients run old software as well as new;
• followed site safety systems without being reminded: permits to work, lockout and tagout, and inductions.

If you are still building that experience, keep building it as an employee. An integrator will give you variety quickly, and the people you work with there are likely to be your first clients. How to become a commissioning engineer sets out that site experience step by step.

Choose a niche

Generalists compete with everyone. A niche makes you easy to recommend. Pick it along three lines:

• Platform. Siemens (TIA Portal, and the large installed base of STEP 7 and S7-300 systems) or Rockwell (Studio 5000, and older RSLogix 500 systems) are the most common, but a strong niche in a regional platform or a DCS can be worth more.
• Industry. Water, food and beverage, packaging, pharmaceuticals, material handling and energy each have their own standards and habits. Food and pharmaceutical batch work follows ISA-88; pharmaceutical projects add validation work under GAMP 5.
• Task. Migration from obsolete controllers, HMI and SCADA upgrades, commissioning support for machine builders shipping abroad, documentation and I/O checks, or remote support for small plants.

Migration work deserves a special mention. Plants keep controllers for decades, and moving an old system to a current one without stopping production is careful, well-defined work that suits an experienced freelancer.

Where the work comes from

• System integrators with more projects than staff. They need someone who can take a machine or a section of a plant and deliver it to their standard.
• Machine builders who need commissioning engineers to travel with equipment. Demand differs by country; see automation jobs by country and the job board.
• End users with legacy systems, small maintenance teams or a one-off upgrade.
• Former colleagues who have moved on. Referrals are how most freelance work is found.
• Online freelance platforms, mostly for remote tasks such as HMI screens, documentation, simulations and code reviews. Be cautious with any request to change logic on a live plant remotely for a client you have never met. For employed rather than freelance work from home, see remote PLC programming jobs.

Business basics

The details depend on your country, so take local advice on company structure, tax registration and invoicing. These points apply almost everywhere.

A written scope. State the deliverables, the acceptance tests (FAT and SAT), what the client provides (drawings, I/O lists, access, licences) and what counts as a change. Most freelance disputes are about work that was never written down.

How you charge. The usual structures are a day or hourly rate, a fixed price for a defined scope, and time and materials. Fixed price rewards a tight scope and punishes a vague one. Whatever the structure, price and approve changes in writing before doing them, and agree payment milestones and terms up front.

Ownership. State who owns the code, the documents and any reusable function blocks you bring with you.

Insurance. Professional indemnity and public or general liability are commonly asked for. Check each client's contract for the cover it requires.

Safety on site. You are responsible for your own safe working: induction, personal protective equipment, permits, and never working on live equipment outside the site's system.

Software, tools and good habits

Licences. Trial and student licences are generally for evaluation or learning, not commercial work; read each vendor's terms. Use the client's licensed engineering station, or buy your own licences once the work justifies it.

A clean laptop. Engineering tools are version-sensitive. Many freelancers keep separate virtual machines for different software versions, so one project's installation does not break another's.

Backups and version control. Take a backup of every program before you touch it, name versions clearly and hand the client the final archive. Tools such as Git work for text-based code and exports, even where the project file itself is binary.

Documentation. Leave behind what you would want to find: a change log, updated I/O lists, commented code and a short handover note.

Remote access and security

Remote support is convenient and risky. Connect only through the client's approved remote access method, with multi-factor authentication and logged sessions. CISA's guide to securing remote access software explains how attackers increasingly co-opt legitimate remote access tools to reach victims' systems. Never leave your own modem or remote access tool installed on a client's network. Make no change to running logic without the client's change procedure and a backup. The ISA/IEC 62443 standards describe how plants separate their networks, and a freelancer who understands them is easier to trust.

Build a portfolio that breaks no NDA

Most project work is confidential. Build a portfolio from work you own: simulated machines programmed end to end, a write-up of how you would structure a migration, sample HMI screens, a clean function block library. Building an engineering portfolio from course projects shows how to present them. Screenshots from client projects need the client's permission. A verifiable course certificate is supporting evidence of study, not of commissioning; what employers actually check covers how to present it.

Free courses that fill common gaps

1. Siemens TIA Portal Commissioning: hardware configuration, PLCSIM, download and upload, archives, firmware, cross-references, traces and program protection.
2. Siemens S7-300 with STEP 7: the installed base that migration work starts from.
3. Allen-Bradley Studio 5000: CompactLogix and ControlLogix for the Rockwell side.
4. OT and ICS Cybersecurity with ISA/IEC 62443: zones, conduits and risk assessment for anyone working remotely on plants.

The Siemens engineer path and Rockwell engineer path group the platform courses.

Start the courses

The courses are free in full, with lessons from independent creators credited on each course page, EDWartens notes, practice tasks and one final assessment of 15 questions (60% to pass, three attempts). Create a free account to save progress.

The optional EDWartens Certificate of Completion is a small one-off fee, US$8.99 for a beginner course such as S7-300 or Studio 5000 and a little more for an intermediate one such as commissioning or IEC 62443. Anyone can check it at edwartens.com/verification. It is not a Siemens or Rockwell certification, and not an accredited qualification.

Take the free course

Free

PLC programming · Intermediate · Free

Siemens TIA Portal Commissioning: Hardware, PLCSIM, Backups and Troubleshooting

Free

PLC programming · Beginner · Free

Siemens S7-300 with STEP 7

Free

PLC programming · Beginner · Free

Allen-Bradley Studio 5000

Free

Cybersecurity · Intermediate · Free

OT and ICS Cybersecurity with ISA/IEC 62443