Nitecore Explorer (EC1, EC2, EA1, EA2) Round-up Review: RUNTIMES, BEAMSHOTS, VIDEO+

[jhc37013]

I'm starting to really get into to 2xAA lights, I mean sure I've always kept a handful for emergencies but now we are in the 400lmn range with good runtimes. It started for me with the Quark X AAx2 then the ET D25 Clicky and now this EA2, it's not just the output but also the compact size.

The 18650 will still rule for me but these outputs on just 2AA's is mind blowing, sure the body is longer but it's also narrower so EDC'ing a 2xAA isn't all that bad these days. Of course you can always throw in a couple alkalines put it on medium and you have light for probably as long as you need it, it's always been a good feeling knowing you can do that but now you can also get that 350-400 lumens if needed without resorting to lithium batterys.

[BWX]

Opps.. delete this...

[fyrstormer]

These seem to be the most blatant exploitation of the ANSI testing protocol for marketing purposes yet.

The point of a standard in the first place is to define what is considered important enough to measure. If the lights are built to meet the standard, then the standard is working properly. If the lights were not actually useful in real life, that would mean the standard was poorly written, not that the manufacturer is cheating. Certainly the manufacturer can build the product to meet whatever spec they want, but if a standard exists, it is reasonable for the manufacturer to assume that the standard describes how a well-performing product should work. It's not their fault if the standard is defective.

Anyway, I like the way these look. I wonder if Nitecore could be talked into making a Ti version?

[biglights]

Has anyone tried taking the clip off on the EC1?

[selfbuilt]

Has anyone tried taking the clip off on the EC1?

Yes, I have. I recommend the use of a flat-tip jeweler's screwdriver.

A phillips-head screwdriver (even a jeweler's model) typically has very fine endings in the size required to fit through the clip openings. I would be worried about stripping the heads if I tried to use one. A flat-tip screwdriver has a wider head for the same diameter body. Just pick the size that just makes it through the opening in the clip, and you are good to go.

[davidt1]

I really like the size/throw/price ratio of the EC2. It's easily the smallest 18650 light in the picture. It also has the best symmetry and proportion of all the new Nitcore EC lights. Thanks for another fine review.

[biglights]

Yes, I have. I recommend the use of a flat-tip jeweler's screwdriver.

A phillips-head screwdriver (even a jeweler's model) typically has very fine endings in the size required to fit through the clip openings. I would be worried about stripping the heads if I tried to use one. A flat-tip screwdriver has a wider head for the same diameter body. Just pick the size that just makes it through the opening in the clip, and you are good to go.

Thanks Selbuilt that worked, I was worried about stripping the screws. I love this light, but not the clip, always seemed to get in my way. PERFECT now

[selfbuilt]

My continuous red mode runtime on the EC2 is still progressing, but I thought I would share my heat/runtime results so far.

I measured surface temperature using a thermal probe attached to the body right next to the red LED. Basically, this probe was taped in the middle of the "Nitecore" label beside the red LED. I have sorted the table below by the increase in temperature over background room temp.



Consistent with these measures, the EC1 samples (and to a lesser extent the EA1) felt subjectively quite warm to the touch by 1 hour into the run. The whole body felt warm, suggesting a significant power draw off the battery (i.e., it is not just the LED that is heating up).

As you can see in the runtime results in the table, heat was indeed indicative of a high current drain (you can't escape thermodynamics ). There is a clear inverse correlation - lights with low runtimes (indicating high power drain) got warm quickly. Of course, battery capacity has a role here, but there is definitely a very wide swing in power efficiencies among my samples.

Anyway you look at it, <3 hours runtime on the EC1s is disappointing. My EC2 seems to have the best performance - negligible heat, and >4 days runtime so far.

What I don't know is whether these findings are specific to the models in question (i.e., are the EC1 and EA1 always that much worse than the EA2 or EC2?). Or is it simply highly variable across all models? unfortunately, I have no way to answer this, given that I only have one of each. I would be curious to hear other people's experience with runtimes on continuous red.

Regula white mode runtimes are progressing on the other lights, I should have the E2A results up by tomorrow night.

[fyrstormer]

Hopefully someone can confirm whether the bezel ring is removable without damaging the light. I hope it's not press-fit.

[regulator]

Thank you Selfbuilt. It looks like there is a definitely a flaw in the circuit design or manufacture. That's a bummer. I hope they are watching and take quick action to head this off.

Maybe the EC2 delay will help insure that it's circuit is good. The red mode should have super low current draw for long runtimes.

[selfbuilt]

Hopefully someone can confirm whether the bezel ring is removable without damaging the light. I hope it's not press-fit.

I've tried to remove mine using a mouse-pad underside, but no luck so far. But that doesn't mean it wasn't screwed in - just that with nothing to grip on to, it's hard to see how to get it off.

Thank you Selfbuilt. It looks like there is a definitely a flaw in the circuit design or manufacture. That's a bummer. I hope they are watching and take quick action to head this off.
Maybe the EC2 delay will help insure that it's circuit is good. The red mode should have super low current draw for long runtimes.

I've sent my results back to Nitecore, so we will see what their engineers have to say.

One thing - I will have the chance to test a second EA1 sample. The emitter on my current EA1 has failed during runtime testing (a dark spot has appeared on it, and output has dropped). I've never seen anything like this before, but it appears to be a Cree issue, not a Nitecore one. In any case, they are sending me a replacement EA1 so that I can complete the review. I will test its performance on continuous red mode as well.

My EA2 testing is done, just collecting the findings and will post later tonight.

[Phil Ament]

I also notice that under the "Battery Options" heading of all of the Explorer Series instructions that while it says that both CR123 and RCR123 are compatible, it also has the word "Recommended" in brackets next to the CR123. I wonder what that really means and I also hope that Nitecore won't try and use this to suggest that any of our problems or any of the very disappointing run times (mainly constant on red LED) are being caused by the fact that we are using the non-recommended RCR123's.

[selfbuilt]

I also notice that under the "Battery Options" heading of all of the Explorer Series instructions that while it says that both CR123 and RCR123 are compatible, it also has the word "Recommended" in brackets next to the CR123. I wonder what that really means and I also hope that Nitecore won't try and use this to suggest that any of our problems or any of the very disappointing run times (mainly constant on red LED) are being caused by the fact that we are using the non-recommended RCR123's.

No, the product documentation makes it clear that RCR are compatible (and supported) in the EC1 and EC2. Each model has a specific "recommendation" among supported battery types though.

Actually, Nitecore's documentation is probably the clearest I've seen yet, since it specifically lists whether a given battery is compatible or not. The "recommended" is just additional guidance. The manuals also list any specific restrictions (e.g., they identify that the battery indicator feature doesn't work normally on 2xRCR in the EC2).

[selfbuilt]

EA2 runtimes now up:









Again, no surprises here - the EA2 performs well for a XP-G R5 light.

[selfbuilt]

Main review updated with beamshot comparisons of the EC2, EA1 and EA2.

For the EA1, I have included the recent SENS AA as a comparator, as well as the Zebralight SC51 (by special request). For the EA2, all the comparators are XP-G versions of the listed lights. For the EC2, I don't have much in the way of recent XP-G lights, so had to use XM-L based comparators.

Should have the EC2 runtimes up by tomorrow.

[fyrstormer]

I've tried to remove mine using a mouse-pad underside, but no luck so far. But that doesn't mean it wasn't screwed in - just that with nothing to grip on to, it's hard to see how to get it off.

Perhaps an appropriately-sized rubber cork would provide better grip.

[bobjane]

I did a constant red runtime test with an EC1 and AW 750mAh RCR123 charged to 4.18V.

LED went out after 3 hours and 4 minutes. The body was slightly warm throughout, however the ambient temperature is only about 10 Celcius.

Battery came out reading 3.12V. I assume this means the light has its own over discharge protection since the battery's over discharge protection is supposed to be at 2.45V.

[selfbuilt]

I did a constant red runtime test with an EC1 and AW 750mAh RCR123 charged to 4.18V.
LED went out after 3 hours and 4 minutes. The body was slightly warm throughout, however the ambient temperature is only about 10 Celcius.
Battery came out reading 3.12V. I assume this means the light has its own over discharge protection since the battery's over discharge protection is supposed to be at 2.45V.

Yes, others have been reporting the same thing. My EC2 is still running after ~7.5 days on continuous red on a 2200mAh 18650. When it finally stops, I will report the voltage of the cell.

Speaking of which, my runtimes for the white mode of the 18650 are now done:









Again, no surprises for the output/runtime efficiency - the EC2 was excellent for a current-controlled XP-G R5 light (e.g. look at the 4Sevens G5 for a comparison).

One thing that is different - the timed step-down from Turbo to Hi was 27 mins on all battery sources. That's longer than you normally see for most timed step-downs. Note that you can always go back into turbo by simply holding down the button again at this point.

One oddity - on my 2xCR123A run, the light stepped down to Micro instead of Hi after 27mins. I restarted the run at Hi at this point, to allow you to better compare to the other runtimes.

[selfbuilt]

My EC2 red light run finally came to an end last night, somewhere between 8 days 17hrs and 8 days 19 hrs runtime:



It terms of the battery voltage though, the protection circuit had tripped at this point (i.e. 0 volts). So that means the EC2 at least did run the battery down to where the protection circuit engaged.

[selfbuilt]

Just finished the replacement EA1 testing, and added the results to the review. The review is now complete, with revised commentary reflecting all the testing results.

FYI, my original EA1 developed what appears to be a burnt-out area on the emitter (distorting the beam and reducing output). Nitecore dispatched a replacement, so that I could finish this review. Here are the runtimes:











Note: I was unable to complete 14500 runtimes, as the body tube on my replacement EA1 was too narrow to take any of my protected 14500 cells.

I have also tested the red light mode, and added the results to my temp/runtime table:



As you can see, the results fit in with the general correlation - lights that drain the battery quickly on continuous red operation get hotter faster.

Anyway, that brings my detailed testing of this family to a close. Hope you found the runtimes (and everything else) useful!

[chadvone]

Thank You SB for another great review. I like the EA1 as it is , but the runtimes on lower setting are too low for my tastes. Maybe there will be version .2 that they get the runtimes on low and red increased.

[ergotelis]

Selfbuilt, i can see something going wrong on your measurements. I think something is not made right and you numbers seem overrated. Let me explain.

Lets take Nitecore EC2. You are using a AW 2200mah, which is quite a "tired battery", but lets guess that it is still performing quite well.
You are mentioning that EC2 outputs 270 lumen stable for 3hours. 3 hours of discharging for an AW 2200, means about 0,7amp to the led. Even in perfect efficiency, which we don't have anywhere, it won't be higher than 0,8amp, without of course counting the fact that this AW won't perform as it did in its first cycles.
According to cree, a xp-g R5, @0,7amp,@25 C has output of 260-280 lumen. Do you get the Point?

If we add the higher temp, maybe almost 70 C on the core, the lumen loss due to reflector and glass, we won't be getting more than 230 lumen from the flashlight. And this is for a top bin led xp-g S2, for example. My estimation, about 200 lumen OTF, for a classic xp-g R5.
I don't own the flashlight, i am going to have it soon.

And this possibly happens for all of your nitecore explorer series flashlights, can't comment for the others models other than those of the same form factor. i bet that also on them, EC1, EA2, EA1 , your results are overrated.

[selfbuilt]

Lets take Nitecore EC2. You are using a AW 2200mah, which is quite a "tired battery", but lets guess that it is still performing quite well.

No, I'm afraid you've misunderstood - it is a new battery.

AW still manufacturers and sells 2200mAh cells. In fact, I buy over a dozen new ones every year, usually in batches of 4 every 3-4 months. This is the same for all the other rechargeable cells in my testing. I discard cells after about 40-50 discharge cycles, max (maybe less).

It is fair question to ask for the deailed methodology of my testing. Let me summarize it:

I verify every new battery that arrives to confirm that it performs within the range of early samples (using a standardized set of lights that I run everything though in my lightbox). Capacity outliers are discarded, although that is pretty rare with AW. His cells 2200mAh 18650 and 750mAh RCR protected cells haven been remarkably consistent in rated capacity over time (14500 less so, but still reasonable - there has been a slight increase in capacity over time).

The same is true of my Eneloops. I buy multiple packs of 4xAAA and 4xAA every time they go on sale here, and go through them even faster than Li-ions (probably more like 20-25 cycles on average, maybe less). The reason for that is the occasional over-discharge occurs (i.e. running a light down to off, or nearly there). This is damaging to LSD NiMH - I toss those cells once one of those events occur.

I also maintain an ongoing calibration of lightbox (again using a standardized set of lights, tested at regular intervals). My lightbox design is permanently mounted (i.e., the sensor never moves), and I have determine an internal calibration standard. From inception, I can confirm that there is a <2% drift per year, which I correct for on at least a monthly basis. So the relative output values you see today are entirely consistent with the results from several years ago.

The point is that the internal standard for my lightbox (and all runtime graphs) is tightly controlled and monitored. You can rest assured that results are directly comparable. To use the example of the EC2, the initial turbo output is indeed the same as my samples of the Rofis JR20, Armytek Predator, etc. If I were to run those lights in my lightbox again (with the current calibration), the graphs would be pretty much indistinguishable (I know, because I do this periodically to confirm the calibration).

As to the actual lumen estimate, I have never made any claim to its absolute value accuracy. The method I have used to adjust my interally-consistent and calibrated lightbox values to estimated lumens (and note I always refer to them as such) is based on a statisical relationship developed form an extensive series of comparisons, described in detail here:

How to convert Selfbuilt's Lightbox values to Lumens

The point is that the relative value accuracy of my measures remains remarkably high. So if I estimate one light at 270 lumens and another at 300 lumens, you can feel fairly comfortable with the conclusion that the second light is indeed about 10% brighter. But whether or not that is really 240 and 265 lumens (or 300 and 330 lumens , etc, etc.) I cannot say with any certainty. For that, I am relying on all the results of the 150 or comparison points in the analysis above.

Frankly, there is no way anyone without a properly maintained, properly-sized, NIST-certified, calibrated integrating sphere - used under controlled conditions by a knowledgeable and skilled operator - can asert true, absolute accurate lumens. However, as you will see in the analysis above, I think I have gone to more effort than most in trying to make my estimates as good as they can be.

In any case, I still make no claim to the accurate lumen estimate accuracy. But I do assert that the runtime graphs remain an absolutely well-calibrated and internally-consistent relative set of results from my testing, using only new batteries properly examined for relative performance.

If (and when) AW stops making consistent 2200mAh cells (and Sanyo stops making consitent 2000mAh Eneloops), I am certainly going to have a lot of re-testing to do ...

Again, it is perfectly valid and appropriate to question the methodology used by anyone to report relative or absolute values. Some of this is explained on my flashlightreviews.ca website, and I periodically write up posts like this when queried. I hope that clarifies the situation ... happy to explain further if anything isn't clear. But do check out that other thread for the explanation of the lumen estimation.



Update: I'm gone back to check the full runtime data for the EC2, and the output on Hi is actually closer to ~255 estimated ANSI lumens (using my method above), not 270. This review was an unsual situation, as I rushed to get the summary tables up before leaving town (and thus didn't have the full runtimes of all models). In the case of the EC2, I did quick manual testing of each level in my lightbox at 30secs, and then did hand calculator conversions - looks like something was a bit off on that one. Normally I do the summary tables last, so have complete traces to work from (and automatic Excel generated formulas, so no user error to worry about). Now that all the runtimes are all completed, I will verify all the values against the excel files to confirm.

[ergotelis]

Ok, thanks for all these details, i don't doubt about runtime graphs, just for the lumen estimation method/standard that you have, so, i still insist on that, even if an AW 2200 is new:

"A xp-g R5(even the best ones) is impossible to output 270 lumen for 3 hours from a single 18650 AW 2200" . Is it only me seeing that there is something wrong with this?

For me, either the runtime had to be 2 hours, or the lumen have to be about ~200.

Only a good xp-g2 / xm-l U2 can probably make the numbers selfbuilt posted.

[regulator]

Fantastic SelfBuilt. That was a great read and really helps understand your method of testing. It also provides a lot of confidence when comparing performance of lights (albeit from a single sample). I always look forward to seeing your testing of a new light I am interested in. I also like being able to pull up charts and numbers from multiple lights that you have tested previously to make comparisons.

[selfbuilt]

"A xp-g R5(even the best ones) is impossible to output 270 lumen for 3 hours from a single 18650 AW 2200" . Is it only me seeing that there is something wrong with this?

I have now re-verified all the lumen estimate tables based on the actual runtimes in my excel tables. Most of the results were consistent with my initial reports - the only two that were noticeably off were the EC2 estimate on Hi is (now corrected to ~250-255 depending on battery) and Turbo on EA2 (estimate now corrected to ~355 on my scale).

I warrant that still seems high for the EC2, but a number of factors may be in play here. First, that's only the ANSI FL-1 estimate at 30 secs - after a couple mins, output drops to closer to ~240 lumens on the 18650 Hi mode run. Secondly, (as previously discussed) I agree the absolute value of the lumen estimation may be off - the conversion is only as good as the comparator data in the analysis linked to above.

Third is the battery variation. I have looked up which battery that Hi mode was done on - and it is one that tests at the very top end of my accepted range of capacity of AW 18650 cells. In case you are curious, the acceptable capacity variance range that I use for those 18650 cells is +/- 3.5% from average, upon arrival (measured at ~1A draw). I do this because I find that > ~90% of cells I buy fall within that range upon testing (i.e., I don't need to toss too many outliers). FYI, I also track each individual battery for just this purpose, so I can go back to verify anything unusual results.

Another point is that I do not know what the Vf of the emitter on my particular EC2 sample is (not identified, and I've previously noticed it can have a huge effect on runtimes). For that matter, I don't know if the output bin is really a R5 (that's just what Nitecore reports). It's always possible that that is a minimum spec, and they bundle higher output bins when available as well (e.g., S2?). And as always, where in the bin it falls is unknown (although I think we can assume this sample is good one).

The point is that when you put all those variable in play, it's possible (though uncommon), for all the "stars to align" in the same direction, giving unusually high or low performance for a given light, on a given battery, at a given level. That is certainly true when you consider the uncertainty in lumen estimation - it is the one factor that I cannot fully control for, as I am dependent on a comparison to other known results.

It also provides a lot of confidence when comparing performance of lights (albeit from a single sample).

I am glad to see your parentheses - yes, the other main limitation here is sample variability. I typically only test n=1 of any given light. I thus have no way to know what the typical variation among samples is, and where mine sits relative to the mean. It is always a mistake to assume "typical" performance from any one sample.

It's important for people to think of all these results statistically. I do what I can to limit additional variability introduced by testing, but the fundamental variation is unknown.

[jhc37013]

Selfbuilt great job on not only the review but also your responses to the questions about your testing method, the best simply the best.

[JudasD]

selfbuilt: after your red LED run on the EC1 did you happen to notice what the battery voltage was? Mine ran for alot longer than 2 hours (6 hours to be exact) and my battery voltage was at 3.45 volts. Any thoughts as to why the EC1 would have short LED runtimes compared to the rest of the line?

JD

[selfbuilt]

selfbuilt: after your red LED run on the EC1 did you happen to notice what the battery voltage was? Mine ran for alot longer than 2 hours (6 hours to be exact) and my battery voltage was at 3.45 volts. Any thoughts as to why the EC1 would have short LED runtimes compared to the rest of the line?

No, I'll have to try another runtime and measure it on mine. The 18650 coming out of the EC2 had its protection circuit tripped, but that one ran for over a week (i.e., a much slower current drain). I'll give the EC1 another try when I get the chance.

[jhc37013]

Selfbuilt do you have a dark spot in your EC2's hotspot? Mine has a dark spot in the hot spot, I noticed the EA2 has that hybrid type reflector but the EC2 is a regular smooth reflector and I don't have a dark spot in my EA2, not sure why they didn't use the hybrid reflector in the EC2.

Also your EC2 and EA2 have about the same micro mode output ~1.8 lumens but my EC2 is closer the to the low mode of the EA2 I'd say about 10-15 lumens. Now my EA2 seems to be about equal with yours at the ~1.8 lumen count.

Comparing to different light's I have that I know for sure are around ~300-320 lumens then I'd say my EC2 on max is around the 320 mark.