Phoenix Contact

What is Phoenix Contact?

Phoenix Contact is a family-owned German company based in Blomberg that supplies connection technology, power supplies, controllers, industrial networking components and OT security products for machine building, the process industry, energy and infrastructure. Founded in 1923 in Essen, it is best known for the terminal block on the DIN rail, but today it also offers PLCnext Technology, an open PLC platform, and the FL mGuard family of industrial firewalls and VPN routers. In 2025 the group reported sales of around 3.3 billion euros with roughly 21,000 employees. That puts Phoenix Contact right at the intersection of OT, industrial networking and OT convergence.

🕰️ How did Phoenix Contact come about?

Hugo Knümann founded the company in 1923 in Essen as a sales agency for electrical products, including clamps for the overhead lines of trams. A few milestones show how a terminal maker grew into an automation supplier:

INTERBUS was one of the first German-designed fieldbuses and was later included in the international fieldbus standard IEC 61158. It gave Phoenix Contact know-how in O and industrial communication that carried over into Industrial Ethernet and PROFINET.

🏭 What products does Phoenix Contact supply?

The range is broad and runs from the control cabinet to the cloud:

This combination is unusual: few vendors supply the terminal block and the power supply as well as the PLC, the switch and the firewall. For a machine builder that means one supplier for a complete cabinet; for an OT architect it means many components come from the same security and update chain.

⚙️ What is PLCnext Technology?

PLCnext Technology is Phoenix Contact’s open control platform. A PLCnext Control runs real-time Linux with a deterministic PLC runtime on top. Classic IEC 61131-3 programs, built in the PLCnext Engineer engineering software, run alongside code in higher-level languages such as C++, C# and MATLAB Simulink. A task and synchronisation mechanism ensures that all these programs exchange consistent data within the same cycle.

What sets PLCnext apart from a traditional PLC:

• Open operating system - your own applications and containers can run on the Linux side, for example a Docker or Podman container with analytics software or Node-RED
• PLCnext Store - an app store with ready-made software functions and runtime licences
• Built-in communication - OPC UA server, PROFINET controller and device, Modbus TCP and MQTT for IIoT connections
• Safety - the RFC 4072S combines control and safety (SIL 3 according to IEC 61508) and communicates via PROFIsafe

That makes PLCnext a hybrid of a PLC, an edge computer and a soft PLC. The benefit is flexibility: data analysis, predictive maintenance and a connection to the cloud no longer need a separate industrial PC. The downside is a larger attack surface, because a full Linux system needs the same management as a server, and ransomware or abuse of open services then hits the controller directly.

🔄 How does Phoenix Contact compare with other PLC vendors?

Phoenix Contact is not a PLC market leader like Siemens or Rockwell Automation, but it is one of the largest players in cabinet components and industrial connection technology. Many installations in the Netherlands and elsewhere combine Phoenix Contact terminals and power supplies with a PLC from another brand.

🌐 What role does Phoenix Contact play in industrial networks?

Phoenix Contact supplies industrial switches, WLAN components, media converters and routers for Ethernet networks on the plant floor. The switches support PROFINET diagnostics, ring redundancy and time synchronisation via PTP. For deterministic communication the company is working on TSN, among other things within OPC UA FX.

Two developments stand out:

• Single Pair Ethernet - Phoenix Contact was one of the founders of the SPE System Alliance in 2020 and supports the IEC 63171-2 and -5 connector faces
• Real-time requirements - motion control and energy automation depend on low latency, minimal jitter and redundancy, which require ring protocols and PTP

In energy infrastructure Phoenix Contact also supplies components for substations built to IEC 61850.

🔐 How does Phoenix Contact secure OT networks?

The mGuard line comes from the Berlin security specialist Innominate Security Technologies, which Phoenix Contact acquired in 2008 after distributing its products from 2007. The FL mGuard combines a stateful firewall, VPN (IPsec and OpenVPN), NAT and routing in a DIN-rail housing. In stealth mode the device works transparently at layer 2, so you can shield an existing PLC without changing IP addresses. The mGuard 2000 and 4000 families are certified to IEC 62443-4-2, and the development process follows IEC 62443-4-1.

For remote access Phoenix Contact offers mGuard Secure Cloud, a VPN service through which service engineers connect to machines via a central point. That fits Zero Trust and Defense in Depth, provided you approve and log access per session.

The PLCnext Control family (AXC F 1152, 2152 and 3152) is certified by TÜV SÜD to IEC 62443-4-2 at Security Level 2, with a development process at maturity level 3 under 4-1. The certification only applies with the Security Profile activated and for the certified firmware baseline (2024.0 LTS for the certificate of July 2025). It is a concrete example of Security by Design.

🧯 Which vulnerabilities and incidents are known?

Phoenix Contact products have vulnerabilities too. The company runs its own PSIRT and publishes advisories through CERT@VDE, including in the machine-readable CSAF format. Some examples:

• CHARX SEC charging controllers (2024) - at Pwn2Own Automotive 2024 researchers found thirteen CVEs in the SEC-3000, -3050, -3100 and -3150, three of them rated CVSS 9.8; firmware 1.5.1 fixes them (advisory VDE-2024-011)
• IOCONTROL - the malware attributed to CyberAv3ngers targets embedded Linux devices from vendors including D-Link, Hikvision, Phoenix Contact, Teltonika and Unitronics
• Open platforms - because PLCnext runs Linux and containers, Linux libraries and container images also belong in your patch management

For OT cybersecurity the lesson is not that Phoenix Contact is less secure than other vendors, but that every device with a network port needs an update process. A SBOM helps you see quickly which components are affected.

🧭 How do you deploy Phoenix Contact securely?

A practical approach for an installation with PLCnext controllers and mGuard firewalls:

1. Inventory - record all controllers, switches, routers and firmware versions, including PLCnext Store apps and your own containers
2. Segment - place cells behind an mGuard or another industrial firewall following the Purdue Model and the zones and conduits model, with an IDMZ or DMZ between office and production
3. Activate the Security Profile - only then do the SL2 functions of PLCnext Control apply, such as stricter authentication and user management; combine this with hardening and secure boot where the platform offers it
4. Manage firmware - subscribe to the CERT@VDE advisories, choose LTS firmware and test updates first on a test rig and through FAT and SAT
5. Control remote access - let vendors in only through a controlled VPN, with temporary accounts and logging
6. Secure the lifecycle - include certificates, licences and container versions in lifecycle management

Regulation matters too. In the Netherlands, entities covered by the Cybersecurity Act (in force since 15 August 2026) must include their OT suppliers and supply chain in their risk management; see also supply chain risk. As a manufacturer, Phoenix Contact itself falls under the Cyber Resilience Act: reporting of actively exploited vulnerabilities from 11 September 2026 and full application from 11 December 2027. Other relevant frameworks for your own architecture are ISA-95, NIST SP 800-82 and ISO 27001.

❓ Frequently asked questions

Where does Phoenix Contact come from?

Phoenix Contact was founded in 1923 in Essen by Hugo Knümann and has had its main site in Blomberg, North Rhine-Westphalia, since 1966. It is a family-owned company with around 21,000 employees and 3.3 billion euros in sales in 2025.

Is PLCnext an ordinary PLC?

PLCnext Control works like a PLC running IEC 61131-3 programs, but it runs on real-time Linux and also supports C++, C#, MATLAB Simulink, apps and containers. That makes PLCnext more of a combination of PLC and edge computer than a classic closed PLC.

Is PLCnext certified to IEC 62443?

Yes, the PLCnext Control models AXC F 1152, 2152 and 3152 are certified by TÜV SÜD to IEC 62443-4-2 at Security Level 2, with a development process at ML3 under IEC 62443-4-1. The certification only applies with the Security Profile activated and for the certified firmware version.

What is an FL mGuard?

The FL mGuard is a DIN-rail industrial firewall and VPN router from Phoenix Contact. An mGuard separates machine cells from the rest of the network and, in stealth mode, can protect an existing PLC without changing IP addresses.

How do you keep track of vulnerabilities in Phoenix Contact products?

Phoenix Contact publishes security advisories through CERT@VDE, also as CSAF files that you can process automatically. Link those advisories to your asset inventory so you can see for each Phoenix Contact device whether an update is needed.

Does the Cyber Resilience Act apply to Phoenix Contact?

Yes, as a manufacturer of products with digital elements Phoenix Contact falls under the Cyber Resilience Act. From 11 September 2026 the company must report actively exploited vulnerabilities, and from 11 December 2027 all CRA requirements apply to new products placed on the EU market.

📌 In summary

Phoenix Contact is a German supplier that can fill an entire control cabinet, from terminal block and power supply to PLC, switch and firewall. With PLCnext and the mGuard family it brings open IT technology to the plant floor, which calls for segmentation, active firmware management and following the CERT@VDE advisories.

• Origins - founded in 1923 in Essen, headquartered in Blomberg, inventor of the modular terminal block
• Control - PLCnext combines IEC 61131-3 with Linux, higher-level programming languages and containers
• Security - mGuard and PLCnext are certified to IEC 62443-4-2, with a development process to 4-1
• Points of attention - a larger attack surface from open platforms, known vulnerabilities in products such as the CHARX charging controllers, and CRA obligations for the manufacturer
• Context - relevant to Industry 4.0, MES and SCADA integration and compliance with IEC 62443 and the Cybersecurity Act