Wiring problem in your Fermax DUOX PLUS installation?

At ProFermax , a store specializing in video door entry and intercom technology, we receive daily inquiries from technicians experiencing problems after installing Fermax DUOX PLUS systems. The system won't start, there are intermittent power outages, or the video is poor. The most common cause? Improper wiring and power failure .

Yes, it's that simple. One of the most common mistakes when installing Fermax DUOX PLUS is using unsuitable cables , with insufficient cross-section or low quality. Below, we analyze this problem in depth and how you can easily solve it with the help of the Fermax regenerator Ref. 3268 and other technical advice from our team.

📉 Why can wiring cause a DUOX PLUS installation to fail?

The Fermax DUOX PLUS system works with just two non-polarized wires , making it versatile and easy to install. But this doesn't mean it works with any cable . If you use older telephone cables, cables with a high aluminum content, or cables with different cross-sections, you risk communication problems, video signal interruptions, or failure to open the door.

🔌 Key problem: voltage drop

An inadequate cable causes significant voltage drops , especially when multiple devices are connected, over long distances, or with Wi-Fi monitors. This can lead to unstable power and, consequently, a faulty installation.

At ProFermax , we always recommend using high-quality copper cable , such as parallel, twisted pair, or CAT5, and maintaining the same cross-section throughout the entire cable run. The minimum recommended cross-section? 1 mm² , especially if there are more than 20 terminals or if you're working in video mode.

🔁 What to do if you have already installed with low-quality cable?

If you've already installed one and are experiencing these issues, the solution is to add a Fermax regenerator Ref. 3268. This device is key to recovering the signal and restoring communication quality to the DUOX PLUS system.

🔧 What does the Fermax 3268 regenerator do?

The DUOX 1S DUAL regenerator, Ref. 3268, acts as a bidirectional signal amplifier. It can be placed between long cable runs or between different blocks and allows:

  • Regenerate the video and audio signal in both directions.

  • Avoid interference caused by complex installations or reuse of old wiring.

  • Create new basic facilities , with independent rules for distance and food.

Furthermore, in multi-channel configuration, the Fermax 3268 regenerator allows simultaneous calls to different blocks , ideal for large communities.

📏 Basic rules to avoid problems with a DUOX PLUS installation

At ProFermax , we always insist on adhering to the technical specifications offered by Fermax for a successful installation. Here's a quick summary:

  • Max. 30 terminals per basic installation without regenerators.

  • Recommended topologies :

    • Distribution (max. 2 trunks)

    • Cascade (max. 4 trunks)

    • Star (max. 10 terminals per point)

  • Maximum distance from the plate to the first connection point :

    • Up to 55 meters in cascade or distribution with a trunk.

    • Only 25 meters if there is more than one trunk road.

  • Keep the same cable section throughout the entire route .

And above all: do not mix sections or types of cable within the same installation.

✅ Conclusion: Installing DUOX PLUS successfully is easy... if you choose well

The Fermax DUOX PLUS system is a powerful, modern, and flexible solution, but its performance depends on proper installation. At ProFermax , we recommend all our clients:

  • Don't skimp on the wiring .

  • Plan the network topology according to the distances and number of terminals.

  • Use Fermax 3268 regenerators when signal quality is at risk.

  • And if in doubt, consult our technical support team , always available to help you.

👉 Visit www.profermax.com and find everything you need for a perfect DUOX PLUS installation: regenerators, power supplies, line adapters, and expert advice.

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