DALI: No feedback from the ballast comes in

[Andrey Esaulov]

We have a system with a lot of lights.
They are combined into masts of outdoor lighting, 8 of them.
The system worked for more than a year without any problems.

Now from two masts (16 lights) on one DALI line does not come back. But they are still controlled by their addresses.
Could it be a Logic Machine problem or is there definitely something wrong with the ballasts?
Anything you can advise?


HW: LM5 Lite + Ext (i.MX6)
SW: 20200129

[Daniel]

First bet from me is is DALI power.

[Andrey Esaulov]

First bet from me is is DALI power.

So why do the dimming commands work?

[Daniel]

I've seen many strange things when the power is on an edge. Dali allows for 2V drop. It can be that gateway is able to send telegrams probably even the requests but ballast can't sent it back. Anyway it is just a guess.

[admin]

There are some ballasts that do not adhere to the DALI standard voltage levels when transmitting. This can explain why LM can control them but cannot read the status info. If you say that it worked before then check the wiring. Maybe some contact points became worse over time increasing the total line resistance.