Any DALI experts out there?

[ARW]

I have a dimmer problem but will not bore you with the details unless someone knows something about DALI.

[Bill Wright]

Salvador Domingo Felipe Jacinto Dalí i Domènech, Marquis of Dalí de Púbol (11 May 1904 ? 23 January 1989), known professionally as Salvador Dalí (/?d??li, d???li/[1][2] Catalan: [s?????ðo ð???i]; Spanish: [sal?a?ðo? ða?li]), was a prominent Spanish surrealist artist born in Figueres, Catalonia, Spain.

Dalí was a skilled draftsman, best known for the striking and bizarre images in his surrealist work. His painterly skills are often attributed to the influence of Renaissance masters.[3][4] His best-known work, The Persistence of Memory, was completed in August 1931. Dalí's expansive artistic repertoire included film, sculpture, and photography, in collaboration with a range of artists in a variety of media.

Dalí attributed his "love of everything that is gilded and excessive, my passion for luxury and my love of oriental clothes"[5] to an "Arab lineage", claiming that his ancestors were descended from the Moors.

Dalí was highly imaginative, and also enjoyed indulging in unusual and grandiose behavior. His eccentric manner and attention-grabbing public actions sometimes drew more attention than his artwork, to the dismay of those who held his work in high esteem, and to the irritation of his critics.[6][7]

Bill

[Stephen Early]

Yes, I know about DALI. I have a couple of working systems installed and a copy of IEC-62386 on my desk.

Ask away!

Stephen Early

[ARW]

It's a basic set up repeated three times (ie one dimer controlling two lights).

An Osram DALI MCU is "controlling" two lights that are both fed from a iDrive Quattro CCL driver.

You can power up for the first time and both lights dim nicely together, then after some time (say 5 minutes) one of the lights just turns on to full brightness or both lights turn on to full brightness. The dimmer and power to the lights has not been touched.

[Stephen Early]

I assume these are all completely separate, i.e. the control wires aren't shared between them?

It sounds like the lights are going into "system failure" mode - when the control signal is missing for more than 450ms they change to the pre-programmed "system failure" output level, which by default is

100%.

Is this affecting all three installations, or just one of them?

The way DALI works is that there's a current-limited power supply to the control lines, providing between 12v and 20.5v with up to 250mA available. The various parts of the system communicate digitally by modulating their current draw from the DALI control lines to drop the voltage; all DALI system components can sink at least 250mA from the control lines. A voltage between 9.5v and 22.5v on the control lines is interpreted as "high level" and anything below 6.5v is interpreted as "low level".

If the voltage on the control lines at the driver drops below 6.5v for more than 450ms at a time, the driver will go into system failure mode.

How have you wired the systems? What size conductors have you used for the control signals, and how long are they? The usual recommendation for DALI is 1.5mm^2, going up to 2.5mm^2 for particularly large systems or long cable runs. What's the voltage on the control lines at the driver when the dimmer is not being touched? How about at the dimmer?

I assume you are using the DALI power supply built into the Osram DALI MCU (i.e. you're supplying 230v to the L and N connections on it)? If not, where is the control line power supply coming from?

Stephen Early

[Tjoepstil]

he painted some weird shit. Thats all I can remember.

[Stephen Early]

Ugh. I hate it when manufacturers do that!

USB to RS485 ought not to be too bad - they are fairly common. £1-2 on fleabay, or £20 for a good FTDI one from RS.

USB to DALI is a different matter! They price gouge because they can, because they aren't commonly available. And probably because the standards organisations charge a fortune for a copy of the standard, too.

Hmm. Overridden for how long, I wonder?

Stephen Early

[Andrew]

"The installation of the DALI PCU is an easy as it gets:" :-)

[Dave Liquorice]

I visited the place in 1993 (SW China).