Can I Use an Existing Dimmer in Combination with a Shelly RGBW2, Dimmer, DUO, Bulb (or any other Shelly)?

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Can I Use an Existing Dimmer in Combination with a Shelly RGBW2, Dimmer, DUO, Bulb (or any other Shelly)?

 

KERRY CLENDINNING·WEDNESDAY, FEBRUARY 12, 2020·

The answer is simply no.

The input to the RGBW2 is low voltage DC, and your existing dimmer switch is AC. (There is some confusion around the device included with the RGBW2, but it does not enable a dimmer switch to work, despite a somewhat ambiguous diagram we’ll discuss later.)

Though the input for the Shelly Dimmer is AC, same answer goes: no. An existing switch or button with built in dimming can neither drive the “L” input to the dimmer, nor should it be wired to the switch input. Only a simple switch or pushbutton should be wired to the input on either the Dimmer or other Shelly devices.

In the case of both the RGBW2 and the Dimmer, you have options to use a momentary pushbutton whose default behavior will be as follows: push briefly to toggle the power on/off at the existing brightness. Push-and-hold the button to alternately raise or lower the brightness level. When the Shelly product reaches either extreme it stops changing (doesn’t reverse until you release and then hold the button again).

Shelly Bulb, Duo and Vintage are designed to be powered by regular house current and cannot be used on a circuit wired to a dimmer. Not even the Shelly Dimmer can work to power Bulb, Duo, Vintage, or any other Shelly lighting product.

For the relay-type products (Shelly 1/1PM/2.5/4Pro), a switch or button is also all that can be connected to their switch inputs. They provide no dimming features, but there are things you can do with a “long press” of the button. See the documentation on the “actions” menu or a document on direct device-to-device communications for more info on the long-press features.

Now, back to the RGBW2 and this diagram:

The label “AC (110-230V) ON/OFF/dimming switch” has created some confusion for people. This is not intended to mean that a dimmer can be connected to the the input of the device shown in black and having four cables. It simply means that if a momentary button (or a spring-loaded paddle), rather than a two-position switch, is connected in the fashion shown, it will be able to control the on/off/dimming of the Shelly Dimmer itself, with the press on/off and press-and-hold to dim/brighten functionality described already.