Fermax Universal 3399 Loft Ring signal not detected

Hi all,

Try to configure a 3399 Loft Universal Fermax, Opener can’t detected ring signal.

Any issue known for Fermax 3399?

Ground switch select to common ground.

Any trace on (or debugger on) options to see voltage detection on ring?

I’ve tried with generic analogic model too. But without luck.

Thanks in advance.



How Opener detects rings? Voltage between black, purple… (both?) and green wires?

I need discart a fail in opener hardware to send it for replace…

Firmware up-to-date 1.4.6



Hello Francisco,
I have a Fermax VDS Loft 3314 with the opener working (Ring suppresion never worked). I had to rewire & configure several times but at the end I got it working. I am attaching a photo of the connections.

During these configurations I found out that when you are configuring it is very important that at the step of detecting the ring signal the screen of the intercom is already ON before someone rings. Therefore it is necessary that in the step before the detection of the ring signal you can manage to have someone that rings the bell or maybe you can start the intercom camera from inside (I can do it by pressing the camera button of the intercom during 5 seconds).

Hope this helps.


Thanks Gerard.

Fermax 3399 is a universal analogue loft intercom.

I’ve tried many conf. Now I’ve trying only with the essential wire from/to Opener (purple, yellow, and blue). Door open works perfectly, but ring detection never works.

So, witch voltage between yellow and purple wires trigger a good detection from Opener? I’ve thinking make a simple interfase (may be optocoupler or simple relay)… or to mount a mini-lab and try more combinations on the desk.



Hi again.

Nobody know voltage trigger ring detection?

Technicals docs. about this?



Hi Paco,

I have a Fermex 3399 and was having trouble making it work.

I tried all sorts of ways.

Finally, I had overlooked the step in the instructions to actually disconnect the Opener from the ribbon cable, then wire it per the instructions, plug it back in to the Opener and complete the rest of the configuration steps.

Then it worked for me.

Now I wish the Apple Watch LTE could open the apartment main door all on its own without an iPhone!!

Hi Kim.

Finally I had to do a laboratory test on my desk in order to make a demonstration to show that my opener unit was broken.!!!

After that, support replace that unit and now works perfectly!!.


1 Like

Buenas,no le harías fotos a la instalación por casualidad, estoy pensando comprar uno y no me fío de si vale o no, tengo el 3399 loft 4+N, gracias

Buenos días.
Sí, tengo fotos. Te adjunto un par.

Un saludo.


Muchas gracias Paco,