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I am new to DALI protocol. The setup has a master and one slave. I am using Mean Well Dali Driver.

Broadcast control commands are working properly. But, I am not able to get the response from Dali Driver, for broadcast query or special commands.

And also I am not able to set short address for the driver. Steps followed by me to set the short address: 1. Initialize Command 2. Randomize Command 3. Program Short Address 4. Query Short Address(Not getting any response)

Thanks.

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  • \$\begingroup\$ What are you using for the DALI power supply? Does it have the right voltage and current limit? Is it integrated with the master? All DALI gear must respond to broadcast queries (for that gear type) when the answer is not No, or it is not compliant, so I suspect a power supply issue. \$\endgroup\$
    – Martin
    Jan 2, 2017 at 10:29
  • \$\begingroup\$ I am using minmax power supply. Power supply specifications: input voltage - 100-240VAC, 100mA mac, 50/60Hz, output - 12VDC /333mA. Dali master is powered through current limiting resistor, output is 12VDC/250mA. Dali driver is not integrated with the master, connected through cables. \$\endgroup\$
    – Amol
    Jan 3, 2017 at 9:26
  • \$\begingroup\$ What is the value of your current limiting resistor? \$\endgroup\$
    – Martin
    Jan 3, 2017 at 9:51
  • \$\begingroup\$ value of current limiting resistor is 480ohm. \$\endgroup\$
    – Amol
    Jan 3, 2017 at 11:40
  • \$\begingroup\$ You said that the master is powered through the current limiter, but is the slave also powered through the current limiter? That 480 ohm resistor limits the current to 25mA which might not be enough for both, although the slave will not draw more than 2mA when not replying. If you connected the slave directly off the 333mA output, bear in mind that PSU spec is a minimum current supplied into a suitable load but DALI requires 250mA maximum current. \$\endgroup\$
    – Martin
    Jan 3, 2017 at 15:52

1 Answer 1

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Start with Command 145, Query Ballast, sent broadcast. If you get no response to this, there are a few possibilities.

  • the gear is not connected or does not have mains power
  • There is too much cable between the power supply/query end and the gear, there is a 2V maximum volt drop specified
  • the gear has a broken transmit transistor, caused by the use of an unlimited or too high a limit on the current limited supply. DALI supplies must be limited to 250mA maximum.
  • the gear meets edition 2 of IEC62386-102 and is in an Operating Mode other than Mode 0.
  • The receiver does not have its threshold voltage between the specified limits.

Once you have fixed this, the command sequence to set a short address when you only have one gear on the bus is

  • Set the DTR to the required short address in the special format (shifted left one place, least significant bit set to 1).
  • Read the DTR to check that it is correct.
  • Send Command 128 Store DTR as Short Address, twice within 100ms, using broadcast addressing.

For this command sequence when you only have one gear on the bus, you do not need to send the Initialise or Randomise command. Whilst it is possible to commission many gear this way, by connecting or powering up one at a time and assigning unique short addresses, it is not normally done this way because of the inconvienience of having to ensure only one gear is on the bus at any one time. Then the randomise method is used, with all the gear powered up at once. Note that with the randomise method, some commands such as Initialise have to be sent twice in 100ms, and that the Program Short Address command is only executed inside gear where the 24 bit search address matched its random address, so your command sequence is incorrect.

My experience with Meanwell gear is that this should work unless you have broken your unit or have field wiring problems.

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  • \$\begingroup\$ Currently looking into programming a DALI setup with python-dali. The software library I have is effectively able to do a commissioning with random short addresses as you describe (only tested it with one lighting fixture atm though). I was just wondering though what happens whenever the master is out; do I need to redo the entire commissioning setup again? Is there any way in the commissions phase to recognize the devices by some of the info they send back? \$\endgroup\$
    – martyn
    Sep 12, 2019 at 19:59
  • \$\begingroup\$ @martyn I would be happy to answer this if you raise it as a seperate question. This format isn't designed for long follow up discussions, for example the comments have to be space limited and without diagrams, as opposed to the answers. \$\endgroup\$
    – Martin
    Sep 16, 2019 at 9:42
  • \$\begingroup\$ thx; I also figured a separate question might make more sense; see electronics.stackexchange.com/questions/458566/… Thx for reaching out! \$\endgroup\$
    – martyn
    Sep 17, 2019 at 20:39

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