How does luminaire performs adaptive dimming based on ambient light?

[John]

Hi,

Test and verify Bluetooth Mesh NLC functionality based on the NCS 3.2.4 and 54L15 by using mesh light ctrl example.

1. Modify the following configurations in the prj.conf of the light ctrl example:
   CONFIG_BT_MESH_LIGHT_CTRL_SRV_TIME_ON=60
   CONFIG_BT_MESH_LIGHT_CTRL_SRV_LVL_ON=32768
   CONFIG_BT_MESH_LIGHT_CTRL_SRV_REG_LUX_ON=700
   Flash the modified example to the 54L15, provision it using the nRF Mesh app, enable OCCUPANCY MODE, and configure the Light LC Server to subscribe to group address 0xC000.

2. Use a Sensor Server to publish an occupancy message to group address 0xC000; the LED on the light ctrl board will be turned on.

3. Use another Sensor Server to publish ambient light messages to group address 0xC000, sending once every 2 seconds with a 25 Lux change each time, but the LED brightness does not change. Change the sending period to 1 second and then 100 milliseconds, but the LED still does not respond.

How to verify that the luminaire performs adaptive dimming based on ambient light?

[Edvin]

Hello,

Sorry for the late reply. I was out of office on Friday.

Are you still using the project that I gave you before the summer in one of your other tickets? It did respond to the brightness change, didn't it? When did it stop doing that?

Are you still bypassing the PI regulator? If so, what does your own regulator look like at this point?

Best regards,

Edvin

[John]

Hi Edvin,

Sorry, we had a long holiday for our country's National Day.

I'm not using a PI regulator and NLC standard for my own light adjustment. We have a mapping table between light brightness and ambient light intensity. For example, below 100 lux, the light is at 100% brightness; below 200 lux, the light is at 90% brightness. The sensor is configured to publish to the group when the ambient light changes by 30 lux. After the devices in the group receive the message, they complete the light adjustment within 1 minute. If a new ambient light intensity message is received within this one minute, the new message is used and the dimming is completed within 1 minute. The dimming time needs to be long enough. If the dimming time is too short, for example 2 seconds, it will cause a breathing-light problem, which is a very bad experience.

Yes, I'm currently using the example you gave earlier to simulate the sensor publishing ambient light messages, and using the default light ctrl example in NCS as the light to receive the messages.

The main reason is that some lighting manufacturers use the NLC standard. If we use our own solution, it won't be compatible with them.

So I want to understand in depth how far NLC can go in adaptive lighting adjustment, and at the same time I want to see what the phenomenon of NLC's adaptive lighting adjustment looks like.

In short, I want to see whether NLC can truly achieve adaptive dimming in real-life usage scenarios.

Best regards,

John

[Edvin]

Hello John,

Ok. It is still a bit unclear to me what you are testing, and what is not working. 

Perhaps you have an application that you can send that reproduces the issue you are seeing? And some instructions on how to test it?

Best regards,

Edvin

[John]

Hi Edvin,

I want to test the NLC's constant illuminance regulation function. When it receives an ambient light message, it should perform adaptive light adjustment. The light adjustment might be very fast, or it might be very slow, but as long as a change can eventually be seen, that's fine.

1. Currently, I am using the light ctrl example, with CONFIG_BT_MESH_LIGHT_CTRL_SRV_TIME_ON=1800 configured, so that the LED stays ON for 30 minutes. I have verified that after receiving an occupancy message, the LED turns on.

2. After the LED turns on, I use the example you previously provided to trigger the publishing of ambient light intensity values via a button, publishing once every 2 minutes, with each change being 100 lux.
   For example, starting from 400 lux up to 1000 lux. According to the constant illuminance regulation principle, the LED brightness should change, but in reality the LED brightness does not change.

Best regards,

John