Phase Dimmers FAQ

What are the pros and cons of the various types of Dimming available in the lighting market?

  • Phase-Cut Dimming
      • The dimming curve of different fixtures may not match (i.e., the light output might not be changing uniformly for all fixture types even though they are commanded to the same dimming level).
      • Phase cut dimming cannot go to low light output levels.  Typically they will bottom out at 20~30% of max intensity
      • Phase cut dimming fixture may flicker at low output levels
      • Phase cut dimming fixtures (and the phase-cut controller) may have an audible hum/buzz at low output levels
  • 0-10V linear dimming
      • The light output level can go down to either 10% or 1% (depending on the driver selected)
      • There can still be differences in the dimming curve between different driver manufacturers.
      • The dimming control is analog and may have some inaccuracy.
      • A CU-4E will be needed
  • DALI/D4i digital dimming (2-wire protocol):
      • The light output level can go down to either 10% or 1% (depending on the driver selected)
      • The DALI standard defines the dimming curve; the drivers will be uniform in their dimming regardless of the manufacturer.
      • The dimming control is digital and, therefore precise.
      • No CU is required. However, if the driver is not SR/Dexal/D4i, a PSU will be required.

Explain the use of Phase dimmers and 3rd party devices?

Before you use phase dimmers, pre-determine whether the fixture supports forward or reverse phase dimming (also referred to as leading edge and trailing edge dimming), and choose a 3rd party device that is appropriate.

The EcoSense device supports only reverse phase dimming, while the Boca Flasher device supports forward phase dimming. Refer to the corresponding articles in the Support Portal.

Some fixtures use a screw-in Edison base LED lamp that supports both forward and reverse phase dimming. However, the designs are customized to use only one type of dimming for the best operation, including supporting the lowest possible dimming levels or flicker.  

The Phase-cut dimmer dims the fixture at line voltage based on a 0-10V signal from the Control Unit (CU).  Though the 3rd party dimmer may have a higher current rating, it is still limited to that of the CU since it is switching the load on and off. Refer to the Enlighted SU-5 and CU-4E with the EcoSense Line Dimming Control diagram.

What is the solution used for MLV (Magnetic Low Voltage) Dimming? 

Forward phase dimmers are used for MLV, reverse-phase for ELV, and third-party devices for line voltage (phase cut) dimming. Refer to Interfacing Enlighted Sensors with Triac and Phase-Cut Dimmable Fixtures using BOCA Flasher Smart Dimmer Control for more details. Please note that the devices used are expensive.

EldoLED Driver FAQ

Are the EldoLED 50W DALI 'Dim to Dark' LED Driver and OSRAM DEXAL LED drivers compatible with the Enlighted 2-wire sensors?

Both Xitanium drivers are compatible with the Enlighted 2-wire sensors, based on DALI features and the SR port power specifications. Note that the EldoLED driver will need an external Power Supply Unit (PSU).

In general, Enlighted sensors are compatible with all DALI drivers. If a driver lacks an internal Power Supply Unit (PSU), then an external PSU must be provided. If a driver lacks energy metering, then the wiring test will conclude with a blinking blue sensor LED. The DALI commands that Enlighted supports for the general case are broadcast only arc power (dimming) commands.  

Are the EldoLED and Osram 0-10v drivers compatible with the Enlighted devices?

In general, CU-4E must be added to the fixture to power the sensor and to ensure that the driver can be turned off. To dim properly, the 0-10V control must be LINEAR dimming. Only the EldoLED Linear 0-10V driver’s dimming option will work properly.

Refer to the line diagram SU-5 and CU-4E with one or more 0-10V Drivers

Drivers FAQ

With Philips XSR drivers, is the power consumption metered or calculated?

The power consumption is metered. The Soft-metering option must be disabled.

Is there a list of drivers that are compatible with the new 2-wire Micro sensor Kit (KIT-SU-5E-D-IoT). Has Enlighted tested the drivers?

Enlighted has tested the drivers, mostly focused on the drivers that have internal ‘power supply units’ or PSU, and also provide hard energy metering.  However, ANY DALI compatible driver, with an external PSU, is compatible with our new 2-wire sensors for basic lighting control (on/off and dimming). See 2-wire Compatible Driver List.

Is there a potential risk of using other drivers by manufacturers, not in the list suggested by Enlighted in the list of Enlighted IoT Ready Drivers and Power Controllers?

  • The drivers or power controllers listed are not the only lists of compatible drivers and controllers. These are the drivers and controllers that Enlighted has tested and verified for our Eco-partners that are found to be compatible. There could be other drivers and controllers in the market that may also be compatible with the Enlighted IoT network. By suggesting this list of verified drivers, Enlighted gives no warranty or guarantee to these drivers' quality, performance, reliability, conformance to any geographical electric code.
  • You can choose to use any brand named DALI driver.
  • Any DALI certified driver that can accept and execute ON, OFF, Dimming, DALI memory inquiry, and support Tunable White models including DT8, CCT control commands from the Enlighted Gen 5 2-wire sensor (SU-5) can be used.
  • The Enlighted Gen 5 2-wire sensors (SU-5) source their power from the DAL Bus Power Supply Unit (PSU). DALI drivers without a built-in Power Supply Unit (PSIU) such as Philips SR and OSRAM Dexal, use an external DALI PSU with the DALI bus.

Is there an updated table of compatible profile 0 drivers?

IoT Ready Profile 0, 0-10V Dimming LED Drivers provides you the required information.

Is there a potential risk of using other manufacturers 

Since you can connect multiple LED drivers to one CU via the 0-10V dim wires, can you do the same for a DALI driver? Connect a 2-wire sensor to two or more DALI drivers. What is the limit?

YES!  Enlighted presently supports up to four DALI drivers on a single 2-wire sensor.

Is there a wiring diagram for two IoT Profile 0 drivers to be connected to one SU-5E sensor?

See line diagram Profile 0 Driver with SU-5 Sensor (02736-04).

What is the difference between profile 0 and profile 1 drivers?

New designs with profile 1 drivers are not recommended and are no longer supported.

The main differences between profile 0 and profile 1 drivers are:

  1. Profile 1 drivers do “digital dimming” vs Profile 0 drivers which do “analog 0-10V dimming, however from an end-user perspective they appear equivalent
  2. Profile 0 drivers do not have energy metering, profile 1 drivers have energy metering.
  3. Profile 1 cannot have multiple drivers connected to 1 sensor (profile 0 can)
  4. Profile 1 drivers cannot have a UL924 power/dimming bypass device for emergency fixtures(commonly used method in the US), it must use a fixture battery backup method.  Profile 0 can use either.

Can one sensor control multiple LED drivers?

Yes – The drivers are connected in “parallel”, that is all AC inputs of the driver are connected to the CU output AC Line output terminals, and all the driver dimming inputs are connected to the CU dimming output terminals. These connections can be done either as ‘star’ or ‘daisy-chain’ wiring.  Proper polarity should be observed in connecting the dimming signal wires. The limitation on the number of drivers that can be connected is based on the driver “AC inrush current” and the dimming wires “source/sink current”.  Refer to the Sensors Spec Sheets and Control Unit Spec Sheets for technical specs.

What is the maximum number of LED Drivers or Ballasts that one Control Unit (CU) can be hooked up to (before the 0-10V voltage drops too low)?

The maximum number of drivers that one CU can be wired to depends on the inrush current from the drivers. The load inrush current not to exceed as specified by the CU spec sheet is  320A peak @ 277V. This will vary from driver to driver. See CU Spec Sheets.

The load rating for the CU 5A@120V and 277V  is also a limiting factor.

INRUSH CURRENT: Can we add the inrush currents (of the drivers to be connected to one CU) together and if they don't surpass 320A (depending on voltage) assume they will work? 

The drivers do not behave differently based on being switched by the same controller so adding the in-rush values would be totally appropriate.

Are the EldoLED 50W DALI 'Dim to Dark' LED Driver and OSRAM DEXAL LED drivers compatible with the Enlighted 2-wire sensors?

Refer to EldoLED Driver.   

Is fixture failure detection based on one sensor one CU per fixture, or multiple drivers and fixtures connected to one sensor and CU?

Fixture failure is on a sensor basis. Sensors do not report which driver has failed when multiple drivers are present in a fixture, or which channel has failed when there are multiple channels. If any or all drivers or any or all channels have a detectable malfunction, then the sensor will report a single fixture failure for the entire fixture.

Is there a 480v solution with Enlighted Control Units or 2-wire sensor and drivers rated for 480v?

Use a stepdown transformer (480v to 277v) with each fixture. 480V drivers are far more expensive and less reliable than 120/277V, and there are many more driver options to choose from.

The following is a Profile 0 driver in 480V from Osram.  Note that no hard energy metering will be available, but if metering is necessary, you will have to get a bench sample of each fixture type and run through the test bench at HQ to build a dimming table to enable software metering.

When using either 0-10, 1-10v, or Dali drivers, how do you turn the drivers to dim or OFF?

When using analog (0-10V,1-10V) drivers, if a CU-4E is present, then there is a relay in the CU which will shut off the power (mains) to the driver when the dimming level is set to 0.  This ensures that ‘typical’ 0-10V drivers will actually turn off, since a 0V input to most ‘typical’ analog drivers will cause them to go to minimum output, not OFF. Refer to SU-5 and CU-4E with one or more 0-10V Drivers (02693-05) line diagrams.

You can also use ‘special’ DIM-TO-OFF drivers, which will turn off the driver output at some control voltage less than 1V.  In this case, a CU is not needed to turn the light off, however, the CU is needed to provide energy metering.  We refer to a DIM-TO-OFF analog driver when no CU is used as a “Profile 0” driver.  The “Profile 0” driver also has the requirement to provide the DC supply for the sensor (12 to 30VDC). Refer to Dim-to-Off Drivers with SU-5 and BZ-50 Power Pack (03143-01) line diagram.

Finally, when using DALI drivers (digital), we use the ARCPWR 0 command to turn the output of the driver off, without shutting off the AC mains to the driver.  There is no need for a CU if using a native 2-wire sensor (or sensor with a 2-wire adapter such as KIT-SU-5E-D).  The sensor power comes from the DALI bus, so there must be a PSU (Power Supply Unit) on the bus.  Newer D4i drivers have a built-in PSU. There is a second option when using DALI drivers (typically without internal PSUs and without internal energy metering) refer to SU-5 (2-wire) with Sensor Ready DALI Driver and LED Array (03068-02) line diagram.  This second option is to use a DALI CU (CU-4D also known as TD- DALICU (02-EN-0).  Again in this case turning off the driver is achieved via ARCPWR 0 command, and the AC mains is never turned off to the driver.  Additionally, the CU-4D will provide energy metering for all of the drivers connected to it.  All dimming commands are sent as broadcast commands to all DALI drivers connected to the sensor or CU-4D, this ensures a simultaneous change of light output refer to SU-5 with CU-4D with one or more DALI Drivers (02945-02) line diagram.


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