120p low runtime?

I see all the run times for novatac on high settings but has anybody seen one at the realy low settings? say level 1 or 2. they must be alot longer than the old hds.

Howdy thermal guy,
Page 13 of the NovaTac instruction manual shows the runtime at level 5 (.33 lumens) as 240 hours. I believe that as the light output is cut in half, the run time is supposed to double...... and using that as a basis, when the light output drops 2 levels to 0.17 lumens, it should get 480 hours, and when it drops the final to levels to level 1 (.08 lumens), it should, theoretically, get 960 hours of continuous runtime.

960 hours, divided by 24 hours in a day, comes out to 40 days.

LED are more efficient at lower drive levels so the runtime is probably more then doubled.

Derek Dean said:

Howdy thermal guy,
Page 13 of the NovaTac instruction manual shows the runtime at level 5 (.33 lumens) as 240 hours. I believe that as the light output is cut in half, the run time is supposed to double...... and using that as a basis, when the light output drops 2 levels to 0.17 lumens, it should get 480 hours, and when it drops the final to levels to level 1 (.08 lumens), it should, theoretically, get 960 hours of continuous runtime.

960 hours, divided by 24 hours in a day, comes out to 40 days.

Click to expand...

I believe somewhere here there is a runtime test of an HDS flashlight on lowest which ended after 45 days. So these calculations are not far from reality.
If only I could find this HDS's runtime...

EDIT: Found it !! http://www.cpfmarketplace.com/mp/showpost.php?p=2124196&postcount=105

Not to mention the HDS locator flash runtime test ... after 23 months ... it'll be two years in September apparently!

Derek Dean,

Although that rule applies well to the mid upper and central brightness levels, it does not apply well to the lower levels. The reason is that there is a higher idle current. Thus as the LED power drops, it eventually becomes equal and then lower than the idle current.

The EDC Ultimate and Basic were good at keeping the idle current very low. As a result, they get exceptionally long run times at very low power settings.

Henry.

I measured mine to have an idle current of 3 micro amps when off, is it the same when on?

Jzmtl,

By "idle current" above, I was referring to the overhead current when the light is turned on but not illuminating the LED. The "sleep" current would be when the light is turned off and 3uA is roughly what it should should be.

You can roughly derive idle current by measuring the current of several low settings - say the lowest 5 settings - and graphing it. You will notice that the curve flattens. By measuring the successive decreases in output, you can closely guess what part of the last reading is contributed by the LED. The rest is idle current.

Henry.

Ah I see, thank, will try that.