Inconsistent data when measuring Philips Hue LTA005 with the utility meter

[edwardtfn]

Hi all,

I'm trying to measure the power consumption of my Philips Hue LTA005 lights, but I'm getting pretty bad data when mired is above 372:

I've used 2 of those LTA005 bulbs and one non-smart LED bulb as a dummy load (11W of dummy load). My measuring device was a Shelly Plus 2PM.

Am I doing something wrong or is this normal for those types of lights (maybe some unsupported light temperature)?

Any thoughts are welcome.
color_temp.csv

[bramstroker]

Hi, you cannot use LED bulbs as a dummy load. Only fully resistant loads (like a inscadent bulb can be used).
I think you should be alright just connecting the two LTA005 bulbs.
I'm not really sure how to read the graph, but it's normal behaviour that the wattage drops a lot on the higher mired values. This is also seen at other lights.

[bramstroker]

Also see here about the LED as dummy load. #1008 (comment).
And there are more references to be found when searching on dummy load in discussion and issues.

[edwardtfn]

I've tried with 3 bulbs and got too many 0's...
I will try to find a better dummy load and repeat the process entirely. Will take a look on the link you shared, but I really want to use something I already have at home (and I'm not sure I will find an old incandescent bulb)...

[bramstroker]

@edwardtfn thanks for your efforts. You can also have a look here. #371. @RubenKelevra was able to put some resistors in parallel with the bulbs. However you must be very careful because of potential heat generated. And also take extra care because you are working with 230 volt.

[RubenKelevra]

Heat generated is minimal when choosing the right amount of wattage on them and spread the load between enough surface area.

With a single one it got to like 80°C, with two it was below body temperature.

[RubenKelevra]

Here's the necessary hardware and setup:

So using a single 20W capable resistor with 10 kOhm isn't great. As stated before it just consumes about 6 W, but it gets fairly hot.

So I'm now using two of them in series which should be still enough, but they shouldn't get too hot that way since each one will only consume a quarter of the power what a single one consumed