Overview

If the light connected to a Wave Dimmer flickers only sometimes, the issue is most likely related to the connected load, dimming compatibility, calibration, or wiring.

This is especially likely when the flickering:

• Does not happen at 100% brightness

• Happens at lower brightness levels

• Starts immediately after switching the light on

• Continues until the dimmer is switched off for several seconds

• Disappears for some time after the light is turned off and back on

This behavior usually points to an unstable LED driver, incorrect calibration, low minimum brightness, or a low-load installation. It is less likely to be caused by Z-Wave communication if the brightness value in the controller stays stable while the physical light flickers.

Recommended checks

Follow the checks below from the most probable cause to the less probable cause.

1. Perform dimmer calibration

Perform the dimmer calibration if it has not been done yet. If the dimmer was already calibrated, run the calibration again and verify that it completes successfully. Calibration allows the dimmer to detect the connected load and adjust the dimming behavior.

Calibration should be performed:

• During first installation

• After changing the bulb or load

• After changing the wiring

• If flickering or unstable dimming appears

If calibration fails, check the load type, wiring, and minimum load requirements.

2. Test with a halogen bulb or known compatible dimmable LED

Test the dimmer with:

• A halogen bulb, or

• A known compatible dimmable LED bulb

If the flickering disappears with a halogen bulb or another known dimmable LED, the issue is most likely related to the original LED driver or bulb compatibility. Some LED bulbs are marked as dimmable but are only stable in part of the dimming range.

3. Increase the minimum brightness level

Increase the minimum brightness level and test again. Some LED drivers become unstable at low dimming levels.

As a test, set the minimum brightness to a higher value, for example:

• 20%

• 25%

• 30%

If the flickering stops after increasing the minimum brightness, the previous minimum level was probably too low for the connected LED load.

4. Increase the startup brightness

If the flickering starts immediately after switching the light on, increase the minimum brightness used when turning the light on. This is useful when the light is switched on at a low brightness level. Some LED drivers cannot start correctly at a very low phase-cut level. They may flicker until they are powered off for several seconds and started again. Set a higher startup brightness and test if the issue disappears.

5. Test with only one bulb

If multiple LED bulbs are connected to the same dimmer, test with only one bulb.

If possible, use bulbs that are:

• The same model

• From the same manufacturer

• With the same power rating

• With the same dimming behavior

Mixing different LED drivers behind one dimmer can cause unstable dimming and flickering.

6. Check load power and neutral connection

Verify the total connected load and the wiring type.

Check if the installation is:

• With neutral

• Without neutral

In no-neutral installations, very low LED (5W or lower) loads can cause unstable behavior because the dimmer must power itself through the load. If the installation is without neutral and the connected load is low, check whether a bypass is required.

7. Check wiring connections

With power turned off, check all wiring connections.

Pay special attention to:

• Live connection

• Neutral connection, if used

• Load connection

• Loose wires

• Poor terminal contact

• Damaged conductors

A loose or poor connection can cause unstable dimming or flickering. All mains wiring checks must be done safely by a qualified person.

8. Test local control only

Test whether the issue also happens when the dimmer is controlled only from the local wall switch. Do not send commands from the Z-Wave controller during this test. If the flickering happens with local control only, the issue is more likely related to the load, wiring, or dimmer configuration. If the flickering only happens when controlled from the gateway, check automations, associations, scenes, or repeated Z-Wave commands.

9. Check the reported brightness value

When the light is flickering, check the brightness value shown in the Z-Wave controller. If the reported brightness value stays stable, but the physical light flickers, the issue is most likely electrical or load-related.

If the reported brightness value changes rapidly, check for:

• Automations

• Scenes

• Direct associations

• Local input events

• Repeated Z-Wave commands

10. Check firmware version

Check the current firmware version of the dimmer. If a newer recommended firmware is available, update the device.

After the update:

• Recheck the parameters

• Run calibration again if needed

• Test the dimming range again

11. Collect a Z-Wave log if the issue remains

If the issue remains after successful calibration and testing with a known compatible load, collect a Z-Wave/controller log. The log should include the moment when the flickering starts.

This helps verify if the dimmer receives any unexpected commands, such as:

• Switch Multilevel Set

• Switch Multilevel Start Level Change

• Switch Multilevel Stop Level Change

• Basic Set

• Commands from associations

• Commands from automations

If no unexpected commands are shown and the brightness value stays stable, the issue is most likely caused by load compatibility, wiring, or electrical behavior.

Troubleshooting summary

Summary

If a Wave Dimmer flickers at lower brightness levels but works correctly at 100%, the most likely causes are load compatibility, calibration, low minimum brightness, low startup brightness, wiring, or low-load behavior. Start by recalibrating the dimmer and testing it with a halogen bulb or a known compatible dimmable LED. If the flickering disappears with another load, the original LED driver is most likely not fully compatible with the dimming behavior. If the issue remains with a known compatible load, collect a Z-Wave log around the moment the flickering starts so the command flow can be checked.