Mag 2 or 3D LED - Help me decide

[ringzero]

i guess that's true. many technical terms are used very liberally on CPF.

but even by those loose standards, i think it's a major stretch to say that a light that has "more than just a resistor and is better than direct drive... can be considered regulated," which is what Robin wrote and the claim that i was trying to provide a counter argument for.

anyway, the OP's original question was, "Do the Mag LED flashlights have a circuit that keeps the light output constant as the batteries run down?" and i was just trying to provide a clear answer. and of course the answer is no... not that there's anything wrong with that.

Everything you write here is correct.

However, by the terminology commonly used on CPF, the MagLED 2D could be described as regulated.

Why?

Because its runtime plot on NiMH cells will be fairly flat until the cells finally give up trying to supply current at the level demanded.

There are MANY lights - way too many to list - that have this characteristic and are described as "regulated" even though they exhibit very rapid output decay when run on alkalines.

What's fair for the goose, is fair for the gander....

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[robostudent5000]

There are MANY lights - way too many to list - that have this characteristic and are described as "regulated" even though they exhibit very rapid output decay when run on alkalines.

those lights are poorly regulated for sure. but their output curves usually decline at a shallower rate than the voltage decline of the battery. it might not be done well, but there's an attempt at regulation.

Mag output curves decline at the same exact rate as the voltage decline of the battery. there's no attempt at regulation.

i think that's an important difference and a distinction worth maintaining. i'm not saying one is better than the other. but i think it's important to maintain precise definitions the best we can.

 

[ringzero]

those lights are poorly regulated for sure. but their output curves usually decline at a shallower rate than the voltage decline of the battery. it might not be done well, but there's an attempt at regulation.

Mag output curves decline at the same exact rate as the voltage decline of the battery. there's no attempt at regulation.

i think that's an important difference and a distinction worth maintaining. i'm not saying one is better than the other. but i think it's important to maintain precise definitions the best we can.

Yes, it's important to maintain precise defintions.

"Current controlled" has a precise defintion.

"Constant output level" has a precise definition.

"Regulated" - as used on CPF - has no precise definiton.

If you look at alkaline runtime plots for the popular 1AA and 2AA Fenix lights, you'll see output declines much faster than what the MagLED 2D exhibits.

Yet those Fenix lights are called "regulated" in the same reviews that contain alkaline runtime plots exhibiting ultra-rapid output decay.

The reviewer often will say something like this: "Although this light has rock solid regulation running NiMH cells, regulation is poor on alkaline cells."

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[lumenal]

I just bought a new 3D cell MagLED yesterday, the current version with a Cree XP-E, and I'm really liking it.

Definitely brighter than my 3D Rebel Maglites. And my 2D Rebel Maglite. Its almost as bright as my 4D Malkoff.

In the city, small pocketable lights are great. Out here in the country, in the sticks, its nice to have a Mag in hand with a couple pocket lights for back-up.

OP: Go with the 3D Cree XP-E Mag.

Side note: after running my 2D Rebel Mag for any more than 10 minutes, the batteries (alkaline) get very warm, because of the high current draw ( 1400ma -1600ma) IIRC.

 

[robostudent5000]

"Regulated" - as used on CPF - has no precise definiton.

If you look at alkaline runtime plots for the popular 1AA and 2AA Fenix lights, you'll see output declines much faster than what the MagLED 2D exhibits.

Yet those Fenix lights are called "regulated" in the same reviews that contain alkaline runtime plots exhibiting ultra-rapid output decay.

The reviewer often will say something like this: "Although this light has rock solid regulation running NiMH cells, regulation is poor on alkaline cells."

so, i think what you're saying is that "regulated" has come to describe, for some people, a flashlight's light output characteristic rather than the characteristics of its circuitry. if that's what you're saying, i guess i can't argue with that. at that point, it's not a discussion about facts.

but if people really mean it that way, then that word has lost a lot meaning because then that means all of my incan lights are regulated too. if i run any of my direct drive incan lights on nimh's, they produce a relatively flat output curve. if people really mean it that way, then every single flashlight ever made can be considered regulated.

 

[ringzero]

so, i think what you're saying is that "regulated" has come to describe, for some people, a flashlight's light output characteristic rather than the characteristics of its circuitry. if that's what you're saying, i guess i can't argue with that. at that point, it's not a discussion about facts.

but if people really mean it that way, then that word has lost a lot meaning because then that means all of my incan lights are regulated too. if i run any of my direct drive incan lights on nimh's, they produce a relatively flat output curve. if people really mean it that way, then every single flashlight ever made can be considered regulated.

Regulated, as commonly used on CPF, seems to refer to a light with a runtime plot that is flat - or flatish - over most of the plot. The flatter the runtime plot, the better the "regulation" is said to be.

"Well regulated" and "semi-regulated" and "poorly regulated" also get tossed around a lot. Lights are said to "fall out of regulation" when cells are depleted and the output nosedives.

Maybe regulation used to refer to something else - constant output or current controlled output - but nowdays it seems to be most commonly used to refer to a flattish runtime plot on a particular type of cell.

It means something else to you, and maybe something else to the next guy, and since it means different things to different people it's not very useful for describing a light.

I try to avoid using the term "regulation" because I think it's too vague to accurately specify anything about a light.

About as useful as saying a light is "bright," which probably means different things to different people.

As to incans running on NiMH cells being regulated, I'd argue that they are.

The NiMH cells are part of the circuitry when the light is operating. That circuitry is driving the output at a near constant level, producing a flatish runtime plot. Although the circuit is very simple, it produces fairly good "regulation."

Some people refer to this setup as a "semi-regulated" light, but if "regulation" is vague, then "regulation" with "semi" or "poor" tacked onto it is even vaguer.

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[robostudent5000]

Maybe regulation used to refer to something else - constant output or current controlled output - but nowdays it seems to be most commonly used to refer to a flattish runtime plot on a particular type of cell.

kind of funny how this went from a discussion about circuits to a discussion about linguistics and semantic change.

cool.

 

[ringzero]

kind of funny how this went from a discussion about circuits to a discussion about linguistics and semantic change.

cool.

If you want to discuss circuits, I'd be happy to oblige.

I'm still unsure of how you define a "regulation" circuit.

I'm guessing that you consider it necessary for "regulation" to have control circuitry with some sort of feedback loop, with a feedback signal used by the circuit to adjust the ouput level.

My main point is this: if you accept that a Fenix 2AA light is regulated, then you have to accept that a MagLED 2D is also regulated.

Both lights have similarly shaped runtime plots on NiMH cells and on alkaline cells.

In fact, the Mag will have a more slowly declining output on alkalines, implying better "regulation."

Are Fenix 2AA lights regulated? If they are, then the MagLED 2D is also regulated.

Most CPF members would say the Fenix 2AA lights are regulated.

If you say the Fenix 2AA lights are not regulated, then your defintion of regulation is in the minority, which makes it even less useful for communicating useful information about any given light.

Cool.

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[robostudent5000]

My main point is this: if you accept that a Fenix 2AA light is regulated, then you have to accept that a MagLED 2D is also regulated.

Both lights have similarly shaped runtime plots on NiMH cells and on alkaline cells.

i would love to see runtime plots that actually show this. do you have links?

btw, there was zero sarcasm intended in the post of mine you were replying to. i genuinely think it's kind of funny the discussion ended up being about semantics and i genuinely think it's kind of cool.

 

[ringzero]

i would love to see runtime plots that actually show this. do you have links?

btw, there was zero sarcasm intended in the post of mine you were replying to. i genuinely think it's kind of funny the discussion ended up being about semantics and i genuinely think it's kind of cool.

Not at my fingertips.

There are many, many runtime plots of Fenix 2AA lights running on NiMH and alkaline cells over in the Reviews forum.

The are plenty of runtime plots of MagLEDs on NiMH and alkaline cells scattered in various Mag threads, but they are fewer in number than what's available for Fenix. It'd probably require a search to find them, which I don't have time for at the moment.

Check out the runtime thread by bigwaffles which has lots and lots of runtime plots, a number of plots for MagLEDs IIRC.

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[Robin24k]

I just bought a new 3D cell MagLED yesterday, the current version with a Cree X-PG, and I'm really liking it.

Are you sure it's XP-G and not XP-E? If it says 484 next to the LED, it's XP-E. So far, only the XL200 uses the XP-G...

 

[lumenal]

Are you sure it's XP-G and not XP-E? If it says 484 next to the LED, it's XP-E. So far, only the XL200 uses the XP-G...

I stand corrected, the LED is XP-E, as it has 484 next to the LED.
Nice light though, even got a nice tint.

 

[Robin24k]

That makes sense...I didn't think Maglite would update the D-cell lights within such a short period of time.

 

[robostudent5000]

Not at my fingertips.

There are many, many runtime plots of Fenix 2AA lights running on NiMH and alkaline cells over in the Reviews forum.

The are plenty of runtime plots of MagLEDs on NiMH and alkaline cells scattered in various Mag threads, but they are fewer in number than what's available for Fenix. It'd probably require a search to find them, which I don't have time for at the moment.

Check out the runtime thread by bigwaffles which has lots and lots of runtime plots, a number of plots for MagLEDs IIRC.

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okay, did a search and found some:

i found bigwaffles's Mag 3D runtime plots, but they were of Mag drop ins, not stock Mag LEDs.
also, i think it's only fair to compare lights with the same battery type. 2AA to 2D isn't an apples to apples comparison as D's have 4x the capacity of AA's and don't always behave the same under load.

here's a runtime of some older Fenix 2AA lights by selfbuilt: link
here's a runtime plot of a 2AA Mag Rebel: link

the Fenix 2AA runtime plots show a relatively flat output curve on alkalines for all the lights listed. the Mag LED 2AA runtime plot shows a rapidly declining output curve on alkalines.

my definition of a regulated light is a light that can maintain a relatively consistent level of brightness as battery voltage drops. those graphs show that Fenix 2AA lights maintain brightness as battery voltage drops and that Mag LED 2AA do not maintain brightness as battery voltage drops. my conclusion is that Fenix 2AA lights are regulated and that Mag LED 2AA lights are not regulated.

but since you were talking about comparing Fenix 2AA to Mag LED 2D, we might just be talking past each other. if the point you were trying to make was that you can achieve the effect of regulation with different battery types, i never would have argued against that. anyway, i'll keep looking for a runtime plot of a 2D Mag LED to see what difference that makes.

 

[ringzero]

okay, did a search and found some:

i found bigwaffles's Mag 3D runtime plots, but they were of Mag drop ins, not stock Mag LEDs.
also, i think it's only fair to compare lights with the same battery type. 2AA to 2D isn't an apples to apples comparison as D's have 4x the capacity of AA's and don't always behave the same under load.

here's a runtime of some older Fenix 2AA lights by selfbuilt: link
here's a runtime plot of a 2AA Mag Rebel: link

the Fenix 2AA runtime plots show a relatively flat output curve on alkalines for all the lights listed. the Mag LED 2AA runtime plot shows a rapidly declining output curve on alkalines.

my definition of a regulated light is a light that can maintain a relatively consistent level of brightness as battery voltage drops. those graphs show that Fenix 2AA lights maintain brightness as battery voltage drops and that Mag LED 2AA do not maintain brightness as battery voltage drops. my conclusion is that Fenix 2AA lights are regulated and that Mag LED 2AA lights are not regulated.

but since you were talking about comparing Fenix 2AA to Mag LED 2D, we might just be talking past each other. if the point you were trying to make was that you can achieve the effect of regulation with different battery types, i never would have argued against that. anyway, i'll keep looking for a runtime plot of a 2D Mag LED to see what difference that makes.

When I have more time I'll post links to specific Fenix runtime plots that illustrate my point. I'll also try to search out plots of MagLEDs running on NiMH cells, which I've seen on CPF but can't recall where.

There are lots of Fenix AA lights that exhibit nearly ruler flat runtime plots on NiMH, but rapidly declining runtime plots on alkalines. This is due to the fact that AA alkies can't source high currents without rapid sagging of output voltage.

Fenix could have designed their circuits to also produce ruler flat outputs on alkalines, but at the cost of very, very short runtimes.

So they compromised with flat outputs when running on NiMH cells, and rapidly declining outputs, but longer runtimes, when running on alkalines.

Very good design decision IMO.

MagLEDs are similar except the D models don't decline as fast as Fenix on alkalines because the bigger D cells can source more current without rapid sagging.

MagLED AA models have similar plots to Fenix AA when run on both NiMH and alkalines.

I've done some runtime measurements on my MagLEDs running on NiMH cells, using a very crude light meter setup. Even my 2AA Rebel MagLED will run for hours with very little decay of output.

The big D-cell MagLEDs do even better on NiMH from runtime plots that I've seen, although I can't confirm it from personal experience because I don't have the NiMH D-cells and a compatible charger.


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[robostudent5000]

MagLED AA models have similar plots to Fenix AA when run on both NiMH and alkalines.

what? no. i just linked runtime graphs that disprove what you say. Fenix 2AA lights in selfbuilt's runtime graph that i linked had flat output on alkalines. Mag 2AA had a fast declining curve on alkalines in its linked graph.

Fenix could have designed their circuits to also produce ruler flat outputs on alkalines, but at the cost of very, very short runtimes.

So they compromised with flat outputs when running on NiMH cells, and rapidly declining outputs, but longer runtimes, when running on alkalines.

neither of those sentences make sense. runtimes are determined by the output level as well as circuit design. Fenix lights have flat output AND long runtime in medium and low modes on alkalines - they didn't compromise. Also, Fenix lights last longer on nimhs than alkalines - selfbuilt's runtime graphs prove that.

Note: i don't know if this is a factor in our discussion, but just so you know, i currently own one Fenix flashlight - an E05 - and i own multiple Maglites. and although i don't have it anymore, until a couple months ago, my main general purpose light was a Rebel MiniMag. when people ask about choosing between an XL50/XL100 and a E21, i generally recommend the E21, but other than that, i like both brands about the same. Mags are good for some things, Fenix good for others.

 

[ringzero]

what? no. i just linked runtime graphs that disprove what you say. Fenix 2AA lights in selfbuilt's runtime graph that i linked had flat output on alkalines. Mag 2AA had a fast declining curve on alkalines in its linked graph.

neither of those sentences make sense. runtimes are determined by the output level as well as circuit design. Fenix lights have flat output AND long runtime in medium and low modes on alkalines - they didn't compromise. Also, Fenix lights last longer on nimhs than alkalines - selfbuilt's runtime graphs prove that.

Have a look at these runtime plots on the venerable Flashlight Reviews:
http://www.flashlightreviews.com/reviews/fenix_l1t-l2t.htm

These were two very popular Fenix models about 5 years ago - considered cutting edge lights at that time.

Output decline of L1T on alkaline is rapid and steep. Output on NiMH declines gradually, then flattens out to a decently long, fairly flat runtime.

Output of L2T on alkalines is flat for maybe 20 minutes, decays linearly for about an hour, then nosedives. Output curve on NiMH is nearly ruler flat for over 2 hours.

The L2T alkaline cells don't have to source as much current as the single L1T alkalne cell, so cell voltage doesn't sag as much. That is why the L2T runtime plot doesn't fall off nearly as rapidly as the L1T plot.

You can easily see the huge difference between alkaline and NiMH in these plots.

Compare the MagLED 2AA of that era:
http://www.flashlightreviews.com/reviews/maglite_minimagled.htm

Output on alkalines decays rougly 25% in an hour, then takes nearly 2 hours to fall another 25%, then nosedives.

Unfortunately, he doesn't have an NiMH runtime for the MagLED 2AA. When I find one I'll post a link. Not as perfectly ruler flat as the Fenix L2T, but it's what most would call a flat runtime plot - looks more like the runtime plot of the L1T, IIRC.

Here it is, from the link you provided for the E20 review:
http://www.candlepowerforums.com/vb...-Comparisons&p=2597020&viewfull=1#post2597020

Scroll down to the first runtime plot, which is for Eneloops.

The old MagLED 2AA Lux is graphed in RED. I'd call that a farily flat runtime on NiMH cells.

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[robostudent5000]

first, IIRC, those 1st gen MiniMags had different circuits than the current ones, so i don't know how relevant a discussion we can have based on that data.

second, comparing runtimes by minutes or hrs only works when drive currents are identical. however, if not, we can still compare the shape of the curves themselves and we can talk in percentages.

the Fenix L2T alkaline curve stays flat near max output for the first 20 percent of its effective runtime, then steadily declines to 75 percent of max before the light basically cuts out. for the initial 20 percent, the light is well regulated. it may not regulate well after that, but there's the proof that it is indeed regulated at some point. we know that alkaline voltages sag under load. for the first 20 percent of its runtime, the Fenix compensates for the voltage sag, and is able to produce a flat output. i.e. the voltage drops, but the output stays the same. this shows that it is regulated.

the 1st gen MiniMag LED curve slopes sharply downward at the beginning losing about 20 percent of its ouput in the first 20 percent of its effective runtime and steadily declines to less than 50% percent of max before it cuts out. the curve is never flat at any point and, i assume, directly follows the voltage drop of the batteries. i.e. voltage drops, output drops with it. this shows that it is not regulated.

by the links you provided, the evidence provides the basis for the conclusion that the Fenix L2T was regulated on alkalines and the 1st gen MiniMag was not.

 

[ringzero]

first, IIRC, those 1st gen MiniMags had different circuits than the current ones, so i don't know how relevant a discussion we can have based on that data.

second, comparing runtimes by minutes or hrs only works when drive currents are identical. however, if not, we can still compare the shape of the curves themselves and we can talk in percentages.

the Fenix L2T alkaline curve stays flat near max output for the first 20 percent of its effective runtime, then steadily declines to 75 percent of max before the light basically cuts out. for the initial 20 percent, the light is well regulated. it may not regulate well after that, but there's the proof that it is indeed regulated at some point. we know that alkaline voltages sag under load. for the first 20 percent of its runtime, the Fenix compensates for the voltage sag, and is able to produce a flat output. i.e. the voltage drops, but the output stays the same. this shows that it is regulated.

the 1st gen MiniMag LED curve slopes sharply downward at the beginning losing about 20 percent of its ouput in the first 20 percent of its effective runtime and steadily declines to less than 50% percent of max before it cuts out. the curve is never flat at any point and, i assume, directly follows the voltage drop of the batteries. i.e. voltage drops, output drops with it. this shows that it is not regulated.

by the links you provided, the evidence provides the basis for the conclusion that the Fenix L2T was regulated on alkalines and the 1st gen MiniMag was not.

So, by your defintion, if a light's runtime plot is flat for the first 20% of the total runtime, then that light is regulated? Very strange definition.

What if it was flat for 10% or 5% or 1% of total runtime? Still regulated?

Noticed you avoided commenting on the L1T. Is it any way regulated on alkaline? Poorly regulated, semi-regulated?

How about the L1T on NiMH? Regulated or not?

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[PCC]

Hello,

I'm trying to decide on a Mag 3D Cree or a 2D Rebel (the 2D Cree is not available locally).

Here is what I see as pros and cons:
The 3D is too heavy with alkalines and Mag claims running rechargeables will severely shorten the LED life. I was considering using Eneloop AA's in the D adaptor.

The 2D is better regarding weight and size, and I really don't notice any difference in the light output. The 2D rebel is rated at 9 1/4 hours runtime and I am leaning toward it. How long can I run the 2D before I notice a diminished brightness?

Do the Mag LED flashlights have a circuit that keeps the light output constant as the batteries run down?

Thanks.

The 2D MagLED is driven harder than the 3D MagLED, regardless of LED used. The Cree 3D MagLED is driven the least hard, by about 100mA, than the Rebel 3D MagLED as measured at the tail cap on the few samples I have at home. My 2D Rebel MagLED is the brightest of the three. That was true when it had the Rebel LED in it and that's even more true now that I have swapped the Cree LED onto the 2D electronics in a 2D Mag. bigC measured this one at around 150 OTF lumens on two NiMH cells. I measured about 1600mA at the tail with the 2D Rebel Mag, about 800mA with the 3D Rebel Mag, and about 700mA with the 3D Cree Mag (all of these numbers are off the top of my head and are subject to correction). It's interesting to note that Mag decided to drive the 3D Cree less hard rather than to allow an increase in brightness owing to the increased efficiency of the Cree XP-E compared to the Luxeon Rebel. This should give slightly longer run times to the Cree MagLED. The smaller die of the Cree XP-E will give you a smaller hotspot and slightly more throw than the Rebel versions. This might explain why lumenal sees the Cree MagLED as being brighter than the 2D Rebel Mag. The 3D Rebel/Cree MagLEDs produce around 90 lumens while the 2D makes around 110.

bigC said at a recent GTG that the 2D Rebel MagLEDs have a circuit that is approximately 50% efficient. I'm tempted to make a long runtime MagLED by making an aluminum tower to replace the plastic one and use a Sandwich Shop Mad Max Plus driver. This should be good for over 200 lumens with an XP-G or 160 lumens with an XP-E. Run times should exceed the 9 hours that the stock 2D Rebel Mag has. I'm going to guess that run times should be around 12 hours or more.