Two-way switching is standard in lighting control. Occasionally,
adding dimming on top of the two-way switching circuit is required. The most
common implementation involves using Single Pole Double Throw (SPDT) switches.
However, as we’ll show, different approaches are possible without SPDT
switches. To address this topic, we’ll cover
Standard approach using SPDT Switches
Two-Way Dimmer Switch with DZ4G450MULT
Dynamic Lighting Controller
The SPST Switch Approach
regular (SPST) light switches, the SPDT switches have three terminals for
To implement dimming using a single-pole dimmer, like DZ3G450DAL, Electricians
shall connect the pair of SPDT switches as per normally required for two-way
switching circuit and add the dimmer at either one of the locations where
dimming control is mostly expected. This approach indeed can dim the lights and
switch them on-off at either location. Note that only a single dimmer is
allowed in the entire circuit.
The DZ4G450MULT Approach
second approach regarding two-way applications is to utilize our DZ4G450MULT dimmer
switch. Besides standalone operations, our DZ4G450MULT supports two-way dimming
control (dimming and switching) by connecting a pair of dimmers by a single
wire (DC) via the T3 terminal available with the units.
As soon as the dimmers are connected, the dimmer unit
connected to the LED lights becomes the “Master” unit, and the other unit that
only has a Live-In connection and single DC connection to the “Master” unit
becomes the “Interface” unit. After connecting the devices, users would find
that different DZ4G450MULT functions replicate at the “Interface” unit location.
As a result, users can switch and dim at both locations. Note either unit can
be the Master unit subject to the wiring. For detail wiring, please refer to the DZ4G450MULT Manual.
Dynamic Lighting Controller Approach
Dynamic Lighting Controller, DZ2G300TUNE, represents another type of
lighting control connection that allows homogeneous operations at
multi-locations. As the faceplates are separate from the controller, we can
connect these faceplates in parallel for a joint return to the controller’s DC terminals.
We used this feature to have two-channel dimming control on two separate
faceplates in residential projects.
The DZ2G300TUNE controller supports Tunable White
LED fixtures. The brightness and color temperature adjustable at more locations
is an exciting application. We know that the same controller is also applicable
to provide a single momentary switch solution for dimming control.
Multi-location dimming control can be realized by simple parallel connection as
described. In practice, residential applications sometimes require using a
single toggle switch control and two-way control together.