About 100 Seconds (D4S)

Hello experts and enthusiasts,

I was just curious if others have taken note of how quickly the D4S heats up when on Max Brightness.

I don’t have any equipment, so I just did the “OK, hot enough - not going toward burn territory” test hand-holding the light.

Maybe the battery (green Shockli) is not quite on par with the black Shockli so the unit heats up a bit faster?

Also, it seemed the SST-20 4000 heated up just as fast or a tad faster than the Nichia, which I thought would be the other way around from reading all the discussion surrounding emitter choices for this light. The difference may well be slight enough that the amateur nature of my experiment puts the observed behavior well within accuracy limits.

Just curious. I know these things get hot and need proper respect.

PS - yes, the full mass of the lights were at room temp, and I did let my hands reach equilibrium between tests.

Thanks

Thanks Peg. I’m not an expert, and I don’t even own a D4S. But I appreciate you doing this bit of testing in case I’m in the market for a D4S in the future! :smiley:

@peg matite, the reason for the SST-20 version of the D4S heating up faster is…

…because it’s not limited to 80% power like the Nichia 219C version.

It therefore goes full power.

My D4 with Nichias and a freshly charged VTC 5a starts stepping down at ~25 seconds and continues for another 5-7 steps, if that matters.

100 seconds is pretty good!

Chris

Thanks. I did not realize the Nichia 219c was throttled like that.

Has this been confirmed?

Then glad I posted. I am definitely a novice, yet already own too many lights, but I sure do like the D4S.

100 seconds sounds like a pretty long time. I’m pretty sure my D4S XP-L HI with a fully charged Shockli cell reaches thermal max much sooner than that.

EDIT: I was wrong. It hit max temp of 52 deg C after about 2 minutes.

At 1 minute, it was at 44 deg C.

If someone would be so kind to borrow me all emitter choices I could make IR thermal videos comparing the lights

But on a light this size it should heat up in 40 maybe 50 seconds to too hot to touch on the head,
but there are not only the emitters also the firmware can be limiting max. Turbo PWM value like the 219Cs were

SST-20 and Nichias have lower forward voltage than XPL-HIs so should draw more current