Fibaro Dimmer 2 compatibility with JUNG 1731DD physical dimmer (regulated phase on S1/S2?)

[copderoc 1]

Hello everyone,

I have a wiring and compatibility question regarding the use of a JUNG 1731DD physical dimmer together with a Fibaro Dimmer 2, and I would appreciate some guidance.

The scenario is the following:

I want to install dimmable LED lighting in a bedroom.

Planned setup:

• A standard JUNG wall switch sends the phase to a JUNG 1731DD dimmer.

• The JUNG dimmer:

  • Receives the switched phase from the wall switch

  • Also receives permanent live (L) and neutral (N)

  • Generates a regulated (dimmed) phase output which goes to the LED load

• This is a standalone physical dimmer, not a smart one.

My intention is to add a Fibaro Dimmer 2 in order to:

• Switch the light on/off via home automation

• Control the dimming level via home automation (if possible)

Here are my doubts:

1. Is it possible to connect the regulated (dimmed) phase output from the JUNG dimmer to S1 or S2 of the Fibaro Dimmer 2?

   • My understanding is that S1/S2 expect a clean live signal, not a phase-cut / dimmed signal, but I would like confirmation.

2. Is it safe or supported to place two dimmers in series (JUNG + Fibaro) controlling the same LED load?

   • Or could this cause malfunction or damage?

3. If dimming from Fibaro is not possible, would it at least be feasible to:

   • Use the Fibaro Dimmer 2 (or another Fibaro module, e.g. a switch) only for ON/OFF control

   • While receiving the dimmed phase from the JUNG dimmer as its input?

4. Alternatively, is the recommended solution to:

   • Remove the JUNG dimmer completely

   • Use only the Fibaro Dimmer 2 for load control

   • And use the JUNG wall switch only as a control input (S1)?

I am attaching the wiring diagrams of the JUNG 1731DD dimmer for reference.

Thanks in advance for any clarification or similar experiences.

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[Tim__ 126]

1. No.

2. No.

3. No, unless you use a device with a relay only eg Fibaro Switch

4. The proper approach is to take out the Jung and add the Fibaro.

[copderoc 1]

Thanks for your reply Tom, option 4, I would like to have a physical regulator, I can only control fibaro from mobile. Perhaps option 3 will be the way. What do you think?

[copderoc 1]

I think the best solution is to use a JUNG momentary (push) switch together with the Fibaro Dimmer 2.

I didn’t know this function before, but as I understand it, by keeping the push button pressed for a certain time (1s, 2s, etc.) I can regulate the light level.
A short press is ON/OFF, and a long press increases or decreases the brightness, stopping when I release the button.

So in practice, this allows me to adjust the light percentage in a similar way to a rotary dimmer, but using a push button instead.

Please correct me if I’m wrong, but this seems to be the cleanest and recommended setup:
one physical dimmer only (the Fibaro), and the JUNG switch used just as a control input.

[Tim__ 126]

If the Jung switch is just a momentary switch, then yes, using it to control the Fibaro Dimmer will work. 😀

[Sankotronic 2,370]

I use Fibaro dimmer 2 with double momentary switches and it works great. With momentary switch S1 it is possible to turn on/off and change dimming level and with secondary switch S2 I use scene activation to do 3 different actions when pressed.