Dali lighting issues

[Druncanduncan]

Good morning all. I have an issue with some dali lighting. Basic system as far as i can tell. Dimmer, controller and 8 button switch. No other inputs that i can find. All on/off/dimming done at switch.
Lights have now stopped working at switch. It's powered as buttons light green when pressed. System has about 20 light fittings off this switch. Power into dimmer. 15v orso coming out. Could this be too low for dali control? Never had to work on dali before so at a total loss. Its a philips system and have been onto their customer service team. Old system. No longer supported. No spare parts. Thankyou and goodbye was their response! The dimmer is a philips dcmd401. It has a red led light on it which says dali status.
Any ideas very gratefully received

Duncan

 

[marconi]

Troubleshooting DALI - Part 1 - What Failed? - https://support.etcconnect.com/ETC/FAQ/Troubleshooting_DALI_-_Part_1_-_What_Failed

might be some help in this link.

 

[ImpededLoop]

Have you powered down the controller? That sometimes sorts them out.

 

[Druncanduncan]

Troubleshooting DALI - Part 1 - What Failed? - https://support.etcconnect.com/ETC/FAQ/Troubleshooting_DALI_-_Part_1_-_What_Failed

might be some help in this link.

Thankyou I'll read thru that

 

[Druncanduncan]

Have you powered down the controller? That sometimes sorts them out.

Hi. Yes I've tried that! Multiple times actually. Can a controller lose its way so needs resetting via software maybe?

 

[plugsandsparks]

As there are no spares available you have limited options. Realistically if you have the mains and dali voltages at all devices, then all i would do is power down for a good half hour (just in case there has been some memory corruption during a brown out. I would power down the dali PSU which is in your photo and all mains from the lights and dimmers. In other words power down everything at the breaker(s), then go and have a long coffee.
Hope this helps.

 

[marconi]

I have never touched DALI technology. But I did read this section in the reference I sent you which might be a clue as to whether the signalling communication is working or not:

DALI Bus Power Supply - DALI is a low voltage protocol that requires that use of the specialized low voltage power supply referred to as a DALI Bus Power Supply. This supply idles at approximately 16 volts DC (16vdc). When messages are transmitted between the DALI Controller and the DALI ballasts, the voltage fluxuates +/- 6 volts depending on the installation. If communication is working, applying an RMS meter ie ac volts to the A and B wires of the DALI loop should produce the fluxuating voltage (when DALI commands are being transmitted).

When idle the AB voltage sits at 16V dc. When signalling it fluctuates plus minus 6V. Thus if you do or do not find +/- 6V fluctuations when DALI controls are operated this might help determine how to proceed perhaps in another call to the manufacturer.

A departing thought is have you changed the batteries in the remote controls and checked indeed they are making contact in their holder?

 

[Druncanduncan]

As there are no spares available you have limited options. Realistically if you have the mains and dali voltages at all devices, then all i would do is power down for a good half hour (just in case there has been some memory corruption during a brown out. I would power down the dali PSU which is in your photo and all mains from the lights and dimmers. In other words power down everything at the breaker(s), then go and have a long coffee.
Hope this helps.

Yes I'll try this as an option. Nothing wrong with a long coffee! Thanks for the reply

 

[plugsandsparks]

I have never touched DALI technology. But I did read this section in the reference I sent you which might be a clue as to whether the signalling communication is working or not:

DALI Bus Power Supply - DALI is a low voltage protocol that requires that use of the specialized low voltage power supply referred to as a DALI Bus Power Supply. This supply idles at approximately 16 volts DC (16vdc). When messages are transmitted between the DALI Controller and the DALI ballasts, the voltage fluxuates +/- 6 volts depending on the installation. If communication is working, applying an RMS meter ie ac volts to the A and B wires of the DALI loop should produce the fluxuating voltage (when DALI commands are being transmitted).

When idle the AB voltage sits at 16V dc. When signalling it fluctuates plus minus 6V. Thus if you do or do not find +/- 6V fluctuations when DALI controls are operated this might help determine how to proceed perhaps in another call to the manufacturer.

A departing thought is have you changed the batteries in the remote controls and checked indeed they are making contact in their holder?

Dali is low speed transmission but still i think it 1.2kb/s . I have never tried the above as i have always had the option to plug a laptop in and look for error messages. You can tell straight away if the controller has locked up as it wont even talk to the laptop. Power cycling as mentioned before has been a good resolution in the past. Because nothing is working it does tend to point to the bus or controller or PSU, if there are voltages at all devices, it at least rules out PSU and bus short / open cct condition, which leaves the controller. I think the problem here is, it is a very old system and he will need some assistance from Philips to get a later Dali controller to work with the switch, dimmer and lights as Dali has evolved over the years and i am not even sure the standard had been set before Philips introduced this product.

 

[Tony M]

Hello All,

Forget most of the above, Most DALI issues are not always what's read from a manual. these are just basics.

A Check each LED driver has a good DALI connection, separated from mains where possible and then ~16V.
B Check the wiring has not dropped more than 2V any where in the system.
C Intertwine (like twisted pair) all Dali wiring where possible. Most important to reduce "Induced Noise"
D Dali Signal Is prone to more noise than we are all led to believe, throw an oscilloscope on, (in Situ), and you will see.
E Add Line repeater's to boost signals where there are long runs and/or a lot of other electronic devices

From installing security cabling for 40 years, i find that many problems are due to poor cabling and noise induced issues.

Hope it helps