2024-02-22
LED driver dimming type
LED driver dimming type
Analog dimming
Analog dimming is often referred to as "0-10 volt dimming". This type of dimming uses a linear potentiometer or a wall-slide potentiometer (such as the Leviton IP710) to control the brightness. In a two-wire dimming system configuration, one driver dimming light has a 10 volt output, and the other wire is a return wire. A potentiometer will vary the voltage between two wires in the range of 0 volts to 10 volts and typically conducts current measured in milliamps. Common potentiometers in such applications have a resistance of 15k to 25k ohms (e.g. 987-1726-ND or 987-1302-ND), but refer to the specifications for specific data. If dimming is not required, these wires are usually left open to achieve maximum brightness; If maximum dimming is required, it can be tied together.
It is also common to dimmer the drive without the help of a potentiometer, but via an external 0-10 volt system. The driver can be dimmed in a similar manner by applying an external 0-10 volt wire (not a 10 volt wire) to the dimming return wire (just tie the two power ground wires together). Some large lighting applications will configure external dimmers through safety circuits or motion detection systems, which can help avoid failures or reduce energy costs.
It is also common to dimmer the drive without the help of a potentiometer, but via an external 0-10 volt system. The driver can be dimmed in a similar manner by applying an external 0-10 volt wire (not a 10 volt wire) to the dimming return wire (just tie the two power ground wires together). Some large lighting applications will configure external dimmers through safety circuits or motion detection systems, which can help avoid failures or reduce energy costs.
DALI dimming
Dimming of the "Digital Addressable Lighting Interface" (DALI) type has always been a type of addressable lighting. DALI supports two-way communication with multiple devices via a single DALI communication line (two-wire), and is not only used for dimming purposes. This type of lighting is considered "smart lighting" and allows users to individually control a single lamp or group of lights and receive data feedback from each lamp at the same time. DALI lighting is controlled by some type of DALI software and is used primarily in manufacturing, but also in commercial and some high-end residential applications.
TRIAC (positive phase) dimming
TRIAC dimming is sometimes called positive or leading edge dimming because these dimming will cut the leading edge of the positive and negative AC voltage waves from the zero voltage point. These "common home dimmers" can be used for inputs to conventional incandescent lighting, resistive loads, and TRIAC dimmable LED drivers. These dimmers are developed from SCRS or thyristors, but unlike thyristors, these dimmers are bidirectional devices that can be used at AC voltage. They cut off the leading edge of the voltage phase, not the trailing edge in ELV reverse dimming.
On the other hand, if you are using the TRIAC for a generic socket or another 120V type LED "bulb" in a home application that lacks a driver, check the original packaging or front panel, which will indicate whether the device is rated for LED dimming. Many cheap TRIAC dimmers that lack LED Settings are labeled as incandescent TRIacs, although they can be used with LED bulbs. In addition, although these dimmers can be used for LED dimming, they generate too much lamp noise and can reduce LED lamp life. Importantly, the dimmer can be rated for LED lighting and can be adjusted in some way to set it from incandescent to LED. LED drivers with TRIAC dimming inputs work well on leds because this is only for dimming reference and is not responsible for performing the actual dimming.
On the other hand, if you are using the TRIAC for a generic socket or another 120V type LED "bulb" in a home application that lacks a driver, check the original packaging or front panel, which will indicate whether the device is rated for LED dimming. Many cheap TRIAC dimmers that lack LED Settings are labeled as incandescent TRIacs, although they can be used with LED bulbs. In addition, although these dimmers can be used for LED dimming, they generate too much lamp noise and can reduce LED lamp life. Importantly, the dimmer can be rated for LED lighting and can be adjusted in some way to set it from incandescent to LED. LED drivers with TRIAC dimming inputs work well on leds because this is only for dimming reference and is not responsible for performing the actual dimming.
ELV (Reversed phase) dimming
"Electronic low voltage" dimming is sometimes called reverse phase or back edge dimming because these dimming will cut off the back end of the forward and negative AC voltage from the voltage peak. While these devices are suitable for resistive loads (such as regular incandescent or halogen bulbs), they were originally designed for capacitive loads (such as LED lighting with or without drivers). These dimmers provide quiet and more reliable LED lighting. These dimmers function similarly to TRIAC except that they cut off the back edge of the voltage phase instead of the front edge. This dimming type is suitable for household LED bulbs that do not use LED drivers and ELV type dimmable LED drivers.
