ABB Controller Selection Guide
How to choose between AC700F, AC800F, and AC900F controllers for your Freelance DCS application.
Quick Recommendation
New projects: Start with AC900F for best-in-class cybersecurity and future-proof capabilities. Cost-sensitive small projects: Consider AC700F for up to ~500 I/O. Existing AC800F systems: Continue with AC800F for consistency, or upgrade to AC900F for new areas.
ABB Freelance Controller Family
The Freelance DCS uses F-line controllers—the "F" designating the Freelance product family. All three generations remain active products with full ABB support. They share the same DigiVis engineering environment and can coexist on the same network.
AC700F
Compact Controller
Entry-level controller for small process applications. Compact form factor with integrated I/O options.
AC800F
Mid-Range Controller
Proven workhorse for medium process applications. Extensive installed base with excellent reliability record.
AC900F
Next-Gen Controller
Latest generation with enhanced cybersecurity, edge computing, and modern connectivity for Industry 4.0.
Detailed Comparison
| Feature | AC700F | AC800F | AC900F |
|---|---|---|---|
| Typical I/O Capacity | ~500 | ~2,000 | ~2,500+ |
| Controller Redundancy | No | Yes | Yes |
| IEC 62443 Cybersecurity | Limited | Partial | Full |
| Edge Computing | No | No | Yes |
| OPC UA Native | Via gateway | Via gateway | Built-in |
| PROFINET Support | Via CI867 | Via CI867 | Native |
| Form Factor | Compact | Modular | Modular |
| Relative Cost | $ | $$ | $$$ |
Selection Decision Tree
1Is this a new project or expanding an existing system?
New Project
Consider AC900F for latest capabilities and longest support horizon.
Existing System
Match existing controllers for consistency, or upgrade new areas to AC900F.
2What is your I/O count and redundancy requirement?
<500 I/O, No Redundancy
AC700F is cost-effective choice.
500-2000 I/O or Redundancy
AC800F or AC900F recommended.
>2000 I/O
Multiple AC800F/AC900F or consider System 800xA.
3Are cybersecurity or edge computing critical requirements?
Yes - Critical
AC900F has IEC 62443 certification and native edge computing.
No - Standard Security
AC700F or AC800F with network security measures.
Application Examples
Small Water Treatment Plant
200 I/O, basic process control, no redundancy required
Chemical Batch Plant
1,500 I/O, batch processing, redundancy required for critical reactors
Pharmaceutical Manufacturing
1,000 I/O, strict cybersecurity requirements, cloud connectivity for analytics
Existing AC800F System Expansion
Adding new production area to existing Freelance system
Important: F-line vs M-line Controllers
ABB maintains two parallel controller families for different market segments:
F-line (Freelance)
AC700F, AC800F, AC900F
Small to mid-size process applications
M-line (System 800xA)
AC800M (PM860, PM861, etc.)
Enterprise-level facilities
Note: M-line did NOT replace F-line. The AC800M superseded the AC450 (Advant Master), not F-line controllers. Both families remain actively developed.
Frequently Asked Questions
What is the difference between AC700F, AC800F, and AC900F?
AC700F is the compact controller for small applications (up to ~500 I/O). AC800F is the mid-range controller for medium applications (up to ~2,000 I/O). AC900F is the latest generation with enhanced performance, cybersecurity, and edge computing capabilities for modern applications.
Which ABB controller should I choose for a new project?
For new projects, the AC900F is generally recommended as the latest generation with best-in-class cybersecurity and future-proof capabilities. Choose AC800F for proven reliability in critical applications. AC700F suits small, cost-sensitive projects.
Can I mix different ABB controllers in one system?
Yes. Freelance DCS architecture supports mixing AC700F, AC800F, and AC900F controllers on the same network. This allows you to choose the right controller for each area based on requirements and upgrade existing systems incrementally.
What is the difference between F-line and M-line controllers?
F-line controllers (AC700F, AC800F, AC900F) are for Freelance DCS—designed for small to mid-size process applications. M-line controllers (AC800M) are for System 800xA—designed for enterprise-level facilities. They are parallel product families, not replacements for each other.
Is the AC700F being discontinued?
No. All F-line controllers (AC700F, AC800F, AC900F) remain active products. ABB maintains long product lifecycles with extended support. The AC900F is the newest addition, but AC700F and AC800F continue to be manufactured and supported.
Related Guides
Need Help Selecting the Right Controller?
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