FAQs on LEDs

If an LED lamp's brightness tends to fluctuate, this may be caused by:

• The dimmer in general and its inability to dim LEDs particularly well
• The selected dimming strategy (leading edge or trailing edge)
• The lamp itself, as the LED driver may be unstable
• It could even be that the lamp and dimmer do not "understand" one another
• If a lamp is not responding satisfactorily, take a lamp from another room that is not experiencing any problems to see if changing the lamp fixes the issue.

Some LEDs tend to dim very quickly from 0 to 100%; this is caused by a poor driver. This makes it difficult to find exactly the right dimming value. If the dimmer permits it, extend the dimming time from 0 to 100%. You will have to spend longer pressing the button to dim/brighten the lighting, but the dimming values can be set more precisely.

Ideally, retrofitted LEDs require a largely constant and interference-free supply voltage from the mains; through the driver integrated internally in the base, this provides a good basis for dimming via the triac. Slight fluctuations in the mains supply can affect the amount of light that is emitted to varying degrees, depending on the driver in the LED.

Insert an RC filter between L and N if necessary.

When replacing the lamp, also replace the transformer if it is older than 4–5 years, as the minimum load may have been dimensioned for a halogen lamp and not for the much lower LED load.

Some isolated cases may involve LEDs clearly flashing. Inrush currents can occur at the point when dimming is switched on and the electronic relay (triac) must use these. A high load may cause the triac to cease functioning or enter a thermal overload state; it will then attempt switch-on again once it has cooled down. When this takes place after the cool-down period, it looks like flashing.

Choose a different dimming strategy if the dimmer permits this. Trailing edge dimming is recommended in this case. Also ensure that the dimmer is well cooled if necessary (distance to the next device).

In the Dimming response – Load selection menu, change the setting from AUTO to RC mode and try again.

In the Dimming response menu, increase the current dimming time values from 0 to 100%. This will smooth to some extent what was likely to have been a parabola-shaped dimming curve and it should then be possible to apply a reasonable setting.

Use a dimming booster in parallel operation. Ensure a distance of approx. 6–8 mm from the dimmer or change the setting on the dimmer to RC and try again.

In stand-alone operation in auto mode / In stand-alone operation in RC mode: 400 W.
In parallel operation – both channels switched together: 800 W.
In parallel operation – both channels switched together + 4 boosters: 1,400 W.

* Important: The parameter setting must be set to RC.

Some isolated cases may involve LEDs clearly flashing. Extremely short inrush currents can occur at the point when dimming is switched on and the electronic relay (triac) must process these. A high load may cause the triac to cease functioning entirely or enter a thermal overload state; it will then attempt switch-on again once it has cooled down. When this takes place after the cool-down period, it looks like flashing.

In the Dimming response – Load selection menu, select Dimming curve 29 and set Fixed RC mode. This should fix the problem. Also ensure that the dimmer is well cooled (distance to the next device).

Check whether the dimmer cable is located close to any large motors, such as elevators, or is even installed in the same cable route. Move the dimmer cable so that it is as far as possible from the motor cables.