All the lights now on this graph are an XPG.
Instead of being mixed in with the XMLs.
I don't like mixing my apples in with my oranges.
You're welcome. I often mix-and-match emitters in the graphs when it is a question of concurrent lights (e.g., some lights can come with either emitter, or people may be considering between recent releases using different emitters). But when I have a fair amount of data on one emitter class, I try to emphasize that when I can.
There was no caveat in the review until I pointed out that the manufacturer stated that it was not recommended to use a RCR123A. In fact, the documentation had a very unusual "Banned" wording for RCR123A when I was reading up on this light just a day before the review came out.
And maybe as a purchaser and user of such lights and batteries you do read the manuals, etc. but then there may also be other people who do not RTFM and rely on reviews from people such as Selfbuilt. His reviews are probably the best ones in this forum so readers may be inclined to simply go on his word about what a light can and cannot use.
There's been a long discussion in ths thread, and I quoted the above only as an illustration. To clarify - my personal policy is always to draw attention in my reviews when I test non-supported battery configurations. In this case, I missed inserting that notice in my charts/graphs and "potential issues" sections when the review was first posted. IronMac pointed that fact out - which I appreciate - and I immediately updated the text with my standard notice.
But I think it is worthwhile that I explain my experience, so you can all see why I test the batteries I do under different conditions, and why I report them.
On the larger matter of non-supported battery types, there is a fundamental problem in terms of language used and their intended meaning. A lot of manufacturers use fairly imprecise or ambiguous wording (e.g., "not recommended"). To its credit Nitecore, has taken pains to provide an explicit table for each model, showing compatible batteries. Next to each cell type, they identify either a "Y (Recommended)", a "Y", or a "N (Banned)". The presumption here is that "Y" by itself means the cell is supported, but not recommended. Most would likely read "N (Banned)" as the voltage range is beyond the circuit specs, likely to cause damage.
In the MT-series lights, however, I think there is some variation in the intended meeting of "N (banned)".
The MT2A lists 3.7V Li-ion 14500 as "banned" quite reasonably - just about any 2xAA light will experience an immediate circuit failure if attempted to be run on 2x14500. I have not tried it on my MT2A, and will not. Keep in mind 2x14500 means ~8.45V initially fully charged, which is a lot more than 2.4-3.0V of approved 2x alkaline/NiMH/L91 cells.
But what to make of the "banned" 1x 3.7V Li-ion on the MT1C and MT1A? I noted the MT1A explicitly supports 3.2V Li-ion ("Y"). This suggested to me that it is unlikely that 1x3.7V Li-ion would blow the circuit in this light. 3.2V nominal Li-ions are typically ~3.6-3.7V fully charged. 3.7V Li-ions are ~4.2V fully charged. That difference is not so great. Note that I would NOT run a 3.7V Li-ion 14500 in a AA light that was only rated for standard AAs (max voltage ~1.5V), as that differential is enough to give me pause that the circuit won't handle it.
What about the MT1C? A fresh primary 3V CR123A is actually typically over ~3.2V initially. As a result, I typically feel quite comfortable testing 1x3.7V Li-ion in 1xCR123A lights. And since I know many of the members here do as well, I provide testing results in this situation so people can know what to expect (with my standard caveat, as always). Note that in all my years, I have never experienced a circuit failure during testing of a 1xCR123A light run on 1x3.7V Li-ion. :shrug:
The 2xCR123A case is more complex. 2xCR123A will have an initial voltage of ~6.4-6.5V, while 2x3.7V Li-ion will be ~8.4V. In many cases, no problem - but I have seen some circuit failures. As a result, I will only test 2xRCR if a manufacturer explictly gives me the okay.
By the time we get up to 4x cells, I will only test what the manufacture explicitly "recommends" or "supports" in published literature. Even at that, I have had quite a few lights fail on supposedly "supported" 4xCR123A. :shakehead As a result, more than one manufacturer has removed "support" for 4xCR123A in 2x18650-model lights after my testing.
The above is just to explain my experience, and my relative risk threshold. Now to explain my reporting policy:
if I am willing to risk testing it, I will report it.
Anything else deprives the reader of the opportunity to draw his/her own conclusions. Ethically, it strikes me as dishonest to collect results and not share them with the community. What data I have, you have.
I realize that is potentially problematic if my relative risk threshold is higher than someone else's. My risk threshold is based on years of testing a large number of lights, and has served me well to date. But I certainly don't wish to impose it on anyone else. This is why I
always draw attention to any deviation of my testing from offically "supported" specs.
I will warrant that there is always a risk that people will look at the graphs/tables and not the read the warnings in the text. But I don't see what else I can reasonably do it about except provide some discussion in the text. Frankly, a greater risk is when people hotlink to the graph/tables images from my reviews without providing a link to the full text, with all its context. This is a practice I strongly discourage, but am often powerless to prevent. :sigh:
As an aside, I've considered trying to put some sort of warning in the images themselves ... but have discarded the idea as unfeasible. Can you imagine doing the 1xRCR graphs while listing in the image legend each manufacturer's specific jargon for support/recommendation/warnings, etc (including all those who say nothing), and constantly re-updating images every time one of them changes it? :sweat: It isn't tenable, especially given the lack of consistency in what each of them often means by a given term/phrase (sometimes within the same model series).
Again, the above is not directed at any specific comment in this thread - I just I thought it was an important issue, and I wanted to explictly explain my testing and reporting rationale for those who were wondering. :wave:
EDIT: one update to the above - in cases where a light looks to be too heavily driven on 1x3.7V Li-ion, I will test it with an IMR cell. The reason is my healthy respect for the discharge limits of ICR chemistry. I cannot directly measure current draw from the emitter, but I can infer from the relative output levels and runtimes if we are entering territory that may exceed ICR's 2C discharge specs. In those cases, I use IMR for battery safety reasons. I also always explictly warn against running any light this way (even with IMR), as it is not lilkely to be good for the emitter (i.e., is unlikely the small mass of a 1xCR123A light will be effective at transfering away the high heat generated). But that's a longer-term stability issue for the light, separate from battery safety. I always recommend people educate themselves on safe battery handling - especially when it comes to rechargeable Li-ions.
