9 Volt Lamp Power Comparison

[tomcat017]

Hi Everyone,

Just wondering if anyone can describe/estimate the difference between running a 9 volt lamp on 3 x CR123s, vs 2 x 17670 or 18650, vs 2 x RCR123s. Specifically, I'd love to know if anyone has any experience with: the SL TL3 lamp, the LF HO-9, or the carley 1499. Of course, if anyone happens to have beamshots, I would humbly and very gratefully request them . Otherwise, if anyone has any experience running any of these lamps on the three setups above (or against each other), I'd love to know. Thanks in advance for the help!! :thanks:

-mike

 

[mdocod]

I'll see if I can help:

each combination of cells, will obviously have different voltage sag, and different runtime.

the TL3, HO-9, and 1499 is a nice little spread for comparison. The TL-3 lamp is pretty similar to a SR-9, Surefire P90, G&P G90, so the results sortof apply to those as well.

The TL3 draws about 1.25A
The HO-9 draws about 1.55A
the 1499 draw about 1.85A

lets start with the CR123s, which can be used to power any of these 3 lamps.
generally speaking, you can expect these cells to sag to about 2.5V each under the load of a TL3, 2.4V into an HO-9, and about 2.3V into a 1499.. so..
[email protected] = ~150 lumen ~60-70 minutes
[email protected] = ~175 lumen ~50-60 minutes
[email protected] = ~200 lumen ~30-40 minutes

Now lets move to the RCR123s. unfortunately, you can't run the 1499 on these cells safely, and the HO-9 is borderline. I won't include the 1499 in these comparisons. Into the load of a TL3, you can expect these to deliver about 3.6V each, into the load of a HO-9 they sag to about 3.4V each.
[email protected] = ~130 lumen ~25-30 minutes
[email protected] = ~150 lumen ~20-25 minutes

Moving up to some 17670 or 18650 cells improves results dramatically. Into the load of a TL3, they will deliver around 3.9V each, into the load of a HO-9 around 3.8V each, and into a 1499 about 3.7V each
[email protected] = ~170 lumen ~70 minutes, ~100 minutes
[email protected] = ~210 lumen ~55 minutes, ~80 minutes
[email protected] = ~250 lumen ~45 minutes, ~60 minutes




these are just some ballpark figures, should be used to make comparisons between the configurations, not to compare to any other specifications or claims elsewhere.

 

[tomcat017]

absolutely awesome, Mdocod! Thanks so much for taking the time to post all that info. Of course, if anyone still has any beamshots, I'd love to see them--but that was exactly what I was looking for! :thanks:

I suppose that the lumens ratings will drop even more drastically for the high-draw bulbs as the run time goes on though, yes? Would there be a point at which the 1499 for example, sags so much that the TL3 surpasses it? I was actually thinking of running a 1499 in the auroralite minimag hotwire kit, as AW confirmed that his RCR123 cells should OK for short run times. But I'm still a little uncomfortable with the idea, and I imagine that they would sag so much that the TL3 might actually be brighter. Well...thanks again!

 

[mdocod]

glad I could help....

there is probably a point where it's not worth driving the higher powered bulb, and not just because they become less efficient (which is a huge reason all by itself), but also because you lose color temperature. As users of lights like the A2 will confirm, color temperature is a huge factor in the *value* of a particular quantity of lumens. The A2 only measures about 80 lumens, but can be more effective than many 100+ lumen lights, because it maintains a high color temperature. Higher color temperatures come with better color rendering indexes, which work better with the eyes for distinguishing depth and colors.

I really don't recommend the 1499 on anything smaller than a pair of 17500s if you want to go li-ion. You'll just be wasting a lot of power into heat (in both the cells and the bulb), and runtime would be terribly dismal.

just for the sake of comparison, a pair of RCR123s, might hold up around 3.25V average under the load of a 1499, or around 6.5V total, about 160 lumen, with a runtime of maybe 10 minutes. I would expect the cells to last at best maybe 20-50 cycles on that setup... it's just not worth it imo... other problem is that the color temperature would probably be down around 3225K or so, not all that impressive.

 

[tomcat017]

Mdococ: Yea, I definitly see your point. The 1499 in the minimag sounds like it just isn't worth it. Probably not that much more impressive than the TL3...and bad for the cells. And as you mentioned, color temp is extremely important. Anyway, thanks again!

 

[DM51]

… RCR123s… the HO-9 is borderline... into the load of a HO-9 they sag to about 3.4V...

HO-9 at 6.8v = ~150 lumen ~20-25 minutes

I have snipped this out of your post #2 above, as it is an impressive combination which I use in a WE Sniper – I think quite a few others use it too. As your figures suggest, I have measured 22 mins with AW cells, although apart from when I did that test I always recharge them early, rather than running them right down.

In a separate thread there was a very interesting discussion between you and SilverFox (how could any discussion between you two be anything other than interesting!) about rated vs. actual output of cells. With a 750mAh rated capacity, a 1.55A current draw is just marginally over the 2C limit, but in theory the excess is so small it is probably OK. However SilverFox has measured that the actual capacity of an R123 under a load like drops from 750mAh to ~500mAh, and this would suggest ~3C with a 1.55A load. My 22 min runtime itself suggests 2.7C.

It is not too kind on the cells, but I don't use it for extended periods. I don't have any way of accurately measuring the output, but I would guess it is quite a bit more than 150 lm. It completely destroys any single-LED light I have seen so far (although a comparison with the WE 170 lm drop-in would be interesting).

In your main comparison guide you give the output as 200 lm rather than 150, and my assessment (purely an eyeball one) would be that 200 is more like it. Has it actually been measured?

EDIT: Annoying that the quote gets split in 2 like that - I twice tried editing the split out, but it reappeared both times.

 

[mdocod]

in my compatability chart, the numers suggest optimal output with fresh cells, in the comparison here I toned it down a bit to gives more average during a discharge... Doing the CR123 to li-ion comparison and giving accurate comparisons requires that I look a little ways into the discharge for things to compare correctly.. mainly because for the first few seconds, a CR123 is REALLY bright on most lamps, but then settles down to the numbers I have above and stays fairly flat for the rest of the discharge. Comparing a midway point on the CR123, means I need to sortof do the same for a li-ion when comparing the 2...

The 2xRCR123>HO-9 when fresh off the charger in a good low resistance host will definetely blow the pants off any single LED out there.