Bug: VMBDALI-20 'Set previous dim value (0x11)' not working

[pvrobays]

Hi community!

I think I’ve detected a very annoying bug with the VMBDALI-20. I hope this is the right place to put this.

Scenario:

1. Set a DALI dimmer light to its maximum: Set dim value to 254.
2. The VMBDALI-20 answers with command 0xA5 (dim value status), with the 254 value (FE)
3. Turn off the DALI dimmer light: Set dim value to 0.
4. The VMBDALI-20 answers with command 0xA5, with the 0 value (00)
5. Send the ‘set previous dim value’ (0x11) command. We assume the light goes back full on.
6. The VMBDALI-20 answers with command 0xA5, with the 254 value (FE)

Great, so you would assume that my light is on, as that’s what the Dali module returns, however: it’s not…

The Dali module is configured to have a fade of 0.7s. Not sure if that has anything to do with this.

Can this be fixed?

Some context:
I’m an owner of a Velbus installation with a VMBDALI-20 module, which I want to intensively use with both Velbus (in combination with velbus push buttons) and Home Assistant (for more complex automations). In home assistant when I turn back on a Dali light, it remains off; however the UI indicates the light is on.
I also have a Signum, but as this doesn’t seem to have support yet for the Dali modules (??) and the integrated HA is limited. That’s why I’m using the community velbus integration.

[MDAR]

Hi

That’s a great report of your findings.

Would you be kind enough to report this via

https://help.velbus.eu

[VEL524]

Both DALI modules should be supported in the Signum. We’ll be happy to take a look, so feel free to submit a support ticket. Include the product name of the driver and a VelbusLink project file.

[pvrobays]

After response on the ticket, it seems like the DALI drivers I use are incompatible with the ‘last active level’ DALI command. Luckily Velbus has a compatibility setting which you can set within your VMBDALI module in Velbus Link:

Enabling this option fixed the issue for me. Hope this can help other Velbus users!