Besides energy saving, controllability is the next highly expected feature of LED Lighting over Traditional Lighting. However, such a control aspect seems to be missing in daily applications. Since 2015, we've been developing & marketing Phase Dimmers* and related products to address LED dimming control

Driven by our project field experience, we developed a new type of Tunable White control using Phase Dimming & 0-10V technologies, which gives our Tunable White Controller (DZ1G300TUNE) & Dynamic Lighting Controllers (DZ2G300TUNE_TOGG / _PUSH). It's our goal to lower the technical and costs barriers for different Circadian Lighting or Commercial applications that desire Multi-Purpose Lighting.

* Our 450W / 220-240Vac Single Live-wire Operational Trailing-edge LED Phase Dimmers released to market includes DZ2G450DIAL & DZ1G450CAPS (2015), DZ3G450DIAL (2017), DZ4G450MULT (2018). In 2017, our DZ3G450DIAL was listed as a SORAA® Compatible dimmer. In Q2 2021, an Enhanced version of DZ3G450DIAL has been available.

In this Application Video Library, we shared a number of interesting topics on LED dimming or how our products can be applied in different scenarios.

Dim-to-Off Inconsistency & Illustration with Mean Well & TCI 0/1-10V Dimmable Drivers

In the last video, we used the TCI DC MINIJOLLY # 122400 and the Legend Tech DZ1G1TEN 1-10V Controller to show that the driver could switch off the light (Dim-to-Off) when we hit below 1V across the DIM+/- input for the driver. This video deep dives into the Dim-to-Off features and uses two drivers to compare their different Dim-to-Off trigger voltages, which helps to show the inconsistency of the Dim-to-Off feature commonly found with 0/1-10V dimmable LED drivers in the market.

Depending on how the current flowing through the 0/1-10V controllers, the controllers can be classified as Sink / Source type of devices.

  • A Sink type controller gets a very small current of current from the driver, approximately in the magnitude of 0.1mA. While the DZ1G1TEN can sink 50mA or more current, this means 500+ drivers can be connected to a single controller simultaneously. The classic Sink type of controller is actually the Potentiometer or Variable Resistor.

  • A Source type controller, on the other hand, has an independent source of current. Thus, these types of controllers usually have 4 wires attached, 2x DC dimming control & 2x its own AC power (Live / Neutral).

In the first part of the video, we use a standard power supply as the current source to flow through the potentiometer (Source mode), which feeds the voltage to the DIM+/- of both the Mean Well LCM-25 & TCI #122400 simultaneously to measure the voltage at which each driver would reach its Dim-to-Off trigger point. From the tests, we saw that TCI driver reached Dim-to-Off at a voltage just below 1V threshold, while the Mean Well driver reached Dim-to-Off at a voltage just above 0V.

In the second part of the video, we disconnected the power supply from the potentiometer, which left only the Variable Resistor to connect to the DIM+/- of the drivers. Configured as a Sink mode, we showed that the same dimming & Dim-to-Off behavior can be achieved, which also means that both drivers can support Sink & Source types of 0/1-10V controllers.

The inconsistency can become a practical problem when either a driver or a controller has been replaced and a different Dim-to-Off behavior is encountered from the new product combination. Again, we emphasize that Dim-to-Off (i.e. Switching off the driver’s light output using a dimmer) is No equivalent to actually cutting off the AC Power to the driver.

Thus, in the next installation, installers should consider/advise the end-customers if Dim-to-Off is really necessary & the possibility of inconsistency issue among the driver and controllers to avoid false expectation.