LIFX Developer Zone

Operating Temperature Range of LIFX LED

What is the range of acceptable operating temperatures for LIFX light bulbs? In particular I would like to know about the 11-watt A19. (Although I and I’m sure others as well are curious about temperature ranges for all lifx products)

I realize there are guidelines posted that say not to put LIFX bulbs in an enclosed fixture, but I have a couple of 11-watt A19s and nowhere for them to go but my new ceiling fan with an enclosed glass dome. So it’s going to happen, but I am modifying the light kit. I already had to modify the fan so these larger than average A19 bulbs would fit under the glass dome. I can further modify the light kit chassis to increase airflow if I need to.

I would like to know the maximum temperature so that I can know when I have done enough modification for the safety of the bulbs. I am using the fixture with the dome off until I find out about the temperature so I can avoid damaging the bulbs.

I’ve asked this of LIFX on a couple of occasions and they would not provide an answer. Possibly because it may be nearly impossible to define. When it comes down to it what matters is the temp of the lamp itself - its electronic components. This can be achieved with very low ambient temps and little airflow or with much higher ambient temps plus very good airflow. How do you specify that?

You may find this interesting: https://bamasotan.us/2019/01/hot-light-fixtures-and-cold-air/

The enclosed fixture bit is interesting because almost all GU10 fixtures are enclosed. It’s kind of like saying we’re going to make a wheel for cars but you can’t use them on cars.

Thanks, @LD1 , that may help.
Since you mentioned surface temperature in your post there, I was curious if you have that data? I only see internal fixture temperature on the chart.

I found this article which refers to lifx temperatures a bit more specifically as well:

From what I understand, the temperature of the electronics inside is what matters, but we can’t measure that. But we can perhaps take the temperature of the exterior surface of the bulb, and given the design, maybe that would indicate a bit of a lower temperature for the inner electronics.

So far I have only been measuring ambient temperature inside the light kit of my fixture, which reached about 108 degrees F yesterday with the dome on (I have the dome off now though). I don’t know if a certain ambient temperature implies the bulb surface and electronics will be a certain temperature in relation. I guess it would depend partially on airflow as you are saying.

I drilled several holes in the top of the light pan, separated the fan motor from the light kit by about 1/2" using washers, and took some temperature measurements using a digital cooking thermometer.

I left the light bulbs in for about an hour on 100% 5500K to warm up. Ambient room temp is 72 F.
With the dome closed, the air inside the light kit directly next to the light bulbs is ~123 F. Just above there, between the fan motor and light kit, it’s ~104.
I took the dome off and immediately tried to get a reading on the body of the bulb, it was 150-160 F.
After waiting awhile with the dome off and not changing the light settings, I got ~107 F where I was getting 123 before.

Do we think this is too hot with the dome on?