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

Blue Robotics Products Lights
1

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?

2

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.

3

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

4

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.