Cebek R-21 module is a dimmer controlled by applying a 0 - 10VDC voltage on to the control terminals. The Cebek R-21 module has the facility to select whether the load is on at 10V or off for a 10V signal. The module will also work using a remotely wired 10kΩ potentiometer. (Not Supplied). This module will not control inductive loads.