Wet blanket on the E01 party

[Probedude]

With the Arc, you can run an AAA cell to near-extinction, then turn off the light and rest the cell for a few minutes, then turn it back on and get a good lighting level for quite a long time (1/2 hour or more), and you can repeat this several times. I'll do a similar test with my E01 when it arrives.

Thanks for the info Paul. Would be neat to know what voltage both lights essentially turn off at - well at least the Arc, I have E01's on order. My usage would be similar to you - I won't be stuck needing a light for hours, just 1-2 mins here and there.

 

[this_is_nascar]

Well, the E01 has ultra flat regulation, i.e. the light output doesn't vary with the battery voltage. What that means in terms of efficiency as the battery runs down, I don't know. There were some tests and graphs of the Arc converter in the electronics forum a long while back. The runtime curve is also well known and can probably be mapped to battery voltage using the various discharge curves for AAA cells (or maybe extrapolating from AA cells) in the battery testing threads.

The Arc does not really try to maximize the total number of photons per battery. As I understand it, Peter through various considerations decided that an EDC light of this type should have 5 hours of runtime. He then made the light as bright as he could within the constraint of having a generic alkaline battery last that long before its sharp drop-off, with some safety margin and taking into account that batteries have varying capacity (so with good batteries you get more like 6-8 hours). That is the reason for semi-regulation as I understand it: he wanted a good output level at 5 hours, but if more power than that was available earlier in the run, he wanted to use it and get more lumens during that part of the run, not save it for more runtime beyond 5 hours.

It looks like 5mm leds are most efficient at around 5-10 mA so perhaps the ultimate in efficiency would be to use three of them like in the Peak Matterhorn 3-led version.

I personally prefer the Arc's semi-regulated scheme since I don't use the light in long enough stretches for runtime to be an issue. Batteries last me for many months. I notice the light getting dimmer when it's maybe halfway down the curve, which means there's still an hour or two left before moon mode, and I know to get around to changing the battery. With flat regulation, I have no such advance warning, it's at a constant level til boom, the light becomes very feeble in an instant.

Ray mentions that the E01 was able to light up at 0.45V, which is pretty interesting--does that mean at a super low glow, or ...?

With the Arc, you can run an AAA cell to near-extinction, then turn off the light and rest the cell for a few minutes, then turn it back on and get a good lighting level for quite a long time (1/2 hour or more), and you can repeat this several times. I'll do a similar test with my E01 when it arrives.

Good stuff. I'm aware of the alkaline cell's ability to recover. What I found that's so intriguing to me is the E01's ability to fire from that low voltage and none of my Arc can. I swapped back and forth, let it rest, etc. Consistantly, every E01 fired and every Arc did not. Now granted, I didn't run it for any length of time, however the light that was coming out the front was useful for close-up conditions.

 

[this_is_nascar]

Thanks for the info Paul. Would be neat to know what voltage both lights essentially turn off at - well at least the Arc, I have E01's on order. My usage would be similar to you - I won't be stuck needing a light for hours, just 1-2 mins here and there.

I used to have that data on the Arc, but I'll be darned if I can find it.

 

[streetmaster]

Man, I love these E01's. They're great for using all those "dead" triple A's in your junk drawer. A few of those dead batteries will run these things for ages. Unbelievable...

 

[GarageBoy]

So how tough is it?/Will it die in a drop?

 

[streetmaster]

So how tough is it?/Will it die in a drop?

I doubt it. They feel pretty solid. I'm not gonna be the one to test it. I like them too much to scratch them up.

 

[this_is_nascar]

I doubt it. They feel pretty solid. I'm not gonna be the one to test it. I like them too much to scratch them up.

Same here.

 

[IcantC]

With the Arc, you can run an AAA cell to near-extinction, then turn off the light and rest the cell for a few minutes, then turn it back on and get a good lighting level for quite a long time (1/2 hour or more), and you can repeat this several times. I'll do a similar test with my E01 when it arrives.

I have done this with my E0 and it worked. I would run alkaline battery down, turn off, rest and turn back on. I made a thread about it, let me find it.

EDIT found it
https://www.candlepowerforums.com/threads/186657

 

[WadeF]

I was told that Fenix runs most of their lights ~ 25mA for the low mode as it is the most efficient current for the Cree's, which 2xTrinity showed in his graphs.

 

[mighty82]

I was told that Fenix runs most of their lights ~ 25mA for the low mode as it is the most efficient current for the Cree's, which 2xTrinity showed in his graphs.

That would certainly explain why they haven't made that "lower low" mode that everyone is screaming about, it would be horribly inefficient. I just wonder how the zebralight does this, while keeping the efficiency on the low level. They don't use pwm right?

 

[2xTrinity]

That would certainly explain why they haven't made that "lower low" mode that everyone is screaming about, it would be horribly inefficient.

They coudl do it in their current regulated lights like the L1D, which have a separate PWM driver to accomplish the strobe and SOS modes. They could use this external driver to PWM the ~30mA low output to get a lower low yet still enjoy that high peak efficiency.

I wouldn't mind if they did it in the L0D, but they'd have to increase the frequency first -- it's irritating even at 15% duty cycle. At 0.2% duty cycle, the 100Hz would be horrible.

I personally prefer the Arc's semi-regulated scheme since I don't use the light in long enough stretches for runtime to be an issue. Batteries last me for many months. I notice the light getting dimmer when it's maybe halfway down the curve, which means there's still an hour or two left before moon mode, and I know to get around to changing the battery. With flat regulation, I have no such advance warning, it's at a constant level til boom, the light becomes very feeble in an instant.

I prefer constant current regulated lights that have low voltage warnigns, and explicitly "blink" when they are running low.

The only advatnage of semi-regulated IMO is that they are a lot "gentler" on alkaline cells though, especially for lights that drive the cells hard, like L0D. Alkalines increase their internal resistance as their capacity wears down, which causes them to sag more, which causes regulated drivers to try to pull even MORE current to compenate -- a vicious cycle. But for low current lights like the E01, CC is fine even on alkaline.

 

[EntropyQ3]

That would certainly explain why they haven't made that "lower low" mode that everyone is screaming about, it would be horribly inefficient. I just wonder how the zebralight does this, while keeping the efficiency on the low level. They don't use pwm right?

Very good point. I never thought to connect those dots before, but it makes perfect sense.

 

[paulr]

The zebralight low is probably in the 20 ma range, which is above that inefficient region.

 

[mudman cj]

Does anyone have a graph showing more detail of Cree efficiency in the 0-50mA range? It's hard to tell from the posted graph what levels of efficiency are under discussion here, and the data sheet I found on Cree's website does not even show this type of data. Thanks in advance.

 

[Jarl]

It may be less efficient, and the 10 lumen level is no doubt very nice to have, but I'd like a balls out low of 1 lumen, and let efficiency be damned. 1 lumen is used when you have night vision, and the extra lumens, even with no increase in runtime, is more of a hindrance than a help IMO.

 

[sino]

It may be less efficient, and the 10 lumen level is no doubt very nice to have, but I'd like a balls out low of 1 lumen, and let efficiency be damned. 1 lumen is used when you have night vision, and the extra lumens, even with no increase in runtime, is more of a hindrance than a help IMO.

There IS a light like that. It's called the Maglite Solitaire. :laughing: Seriously, if you want low lumens and efficiency isn't a priority, there are many low output lights available.

 

[Jarl]

There IS a light like that. It's called the Maglite Solitaire. :laughing: Seriously, if you want low lumens and efficiency isn't a priority, there are many low output lights available.

I want low lumens and the ability to have higher lumens should I need them. The whole idea of a multi-mode light is to take the place of many single mode lights- I don't want to have to take a low output light camping for the specific purpose of getting out the tent at night without waking everyone because of a failing on the part of the multi mode light (i.e, not having a low low mode).

 

[Patriot]

Well, the E01 has ultra flat regulation, i.e. the light output doesn't vary with the battery voltage. What that means in terms of efficiency as the battery runs down, I don't know. There were some tests and graphs of the Arc converter in the electronics forum a long while back. The runtime curve is also well known and can probably be mapped to battery voltage using the various discharge curves for AAA cells (or maybe extrapolating from AA cells) in the battery testing threads.

The Arc does not really try to maximize the total number of photons per battery. As I understand it, Peter through various considerations decided that an EDC light of this type should have 5 hours of runtime. He then made the light as bright as he could within the constraint of having a generic alkaline battery last that long before its sharp drop-off, with some safety margin and taking into account that batteries have varying capacity (so with good batteries you get more like 6-8 hours). That is the reason for semi-regulation as I understand it: he wanted a good output level at 5 hours, but if more power than that was available earlier in the run, he wanted to use it and get more lumens during that part of the run, not save it for more runtime beyond 5 hours.

It looks like 5mm leds are most efficient at around 5-10 mA so perhaps the ultimate in efficiency would be to use three of them like in the Peak Matterhorn 3-led version.

I personally prefer the Arc's semi-regulated scheme since I don't use the light in long enough stretches for runtime to be an issue. Batteries last me for many months. I notice the light getting dimmer when it's maybe halfway down the curve, which means there's still an hour or two left before moon mode, and I know to get around to changing the battery. With flat regulation, I have no such advance warning, it's at a constant level til boom, the light becomes very feeble in an instant.

Ray mentions that the E01 was able to light up at 0.45V, which is pretty interesting--does that mean at a super low glow, or ...?

With the Arc, you can run an AAA cell to near-extinction, then turn off the light and rest the cell for a few minutes, then turn it back on and get a good lighting level for quite a long time (1/2 hour or more), and you can repeat this several times. I'll do a similar test with my E01 when it arrives.

Great post paulr! I really enjoyed that little lesson. It explains a lot.

 

[Ty_Bower]

I want low lumens and the ability to have higher lumens should I need them.

Put your thumb over the end of your high output light. Voilà! Instant low output.