What is the actual power consumption of a single Lumen light?

I searched the specs and the forum.
I found max current of 0.7 amps and 1.5 amps. I got the impression the voltage was about 6 so the power is either 4.2 or 9 watts, assuming 100% efficiency of the switching power supply?

Hi @Rov36,

From the specs on our product page, the peak power usage is expected to be 15 W.
Typical/average usage should be lower than that, but we don’t seem to have a specified value for it, and that does depend somewhat on the temperature (since there’s automatic brightness reduction if it starts overheating).

I just made a few rough measurements at max brightness with my power supply set to a variety of voltages, and got powers between ~4.5 W up to ~6.5 W, but that was also only with a single Lumen so it’s possible there’s greater variation across instances and revisions. It was also starting higher and settling down to a lower power over several seconds after changing the supply voltage, for what that’s worth.

Our specified minimum supply voltage is 7V, although below ~10V the maximum brightness is reduced.

So for a 4S battery (16v) I would expect about 300mA max but maybe 100mA each as a practical level?
I am using an old 2021 Pixhawk purchased as a kit, see below. Will this drive the Lumen lamps? I see a warning that they don’t work with the newer Pixhawk.
Advanced ROV Electronics Package for ArduSub June 2021

That’s largely dependent on your operating conditions and how you’re commanding the lights. If my 6.5W max settled power is indicative of our other Lumens then with 16V you’d expect ~400mA at max brightness, although likely with higher peak current before it settles. If you’re not running them very high then 100-300mA seems like a reasonable estimate, although I’d recommend measuring with your setup if you can.

This comment provides some context - the lights technically worked, but they flickered.

I’m unfortunately not sure on the exact timelines, or when we got the problematic batch. From a quick search of our internal communications it looks like we were investigating the issue in October of 2021, so June could be on the edge one way or the other.