The big LIGHTS thread 2011-2014
Comments
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This is a huge help- thanks gents
@Bartimaeus -
How many of the C8s are you running on your bars?
I'm now asking because I'm thinking of buying a couple as a pressie for my bro-in-law. He needs some bar mounted lights (living with just a helmet one at the moment).
I reckon I'll get him 2x C8 torches for his bars and myself a 501b for my helmet
Any better suggestions for the money?0 -
You appreciate though that there really wont be much difference with the same LED in the 501 vs the C8. The difference is all in the driver and these can be a bit random.
Personally go with the cheaper of the options and order 1 more than you need.
I've just ordered some more XM-L2s as I was sailing at the weekend and it was hilarious comparing my T6 501bs to others navigating with very expensive "yachting" torches, which were mostly XR-E/XP-E lamps. Of course nobody expected the results and now everyone wants one, though I did point out they are not waterproof.
I have also finally worn out some of my laptop cells - after 3 years of regular use! Time to talk to the IT guys again
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ZeeSaffa wrote:@Bartimaeus -
How many of the C8s are you running on your bars?
I have just the one... but if I was starting from scratch I would probably go for 2 of them - one to run on MED (just enough light for just long enough) and one as a boost (very bright for occasional use). But I don't *need* more lights now, and by next winter there will be a choice of XM-L2s... so maybe I'll get lid light upgrade then. The big downside of owning 18650 torches is that it's very easy to justify spending another £10-15 to get a new-and-better one
So for now my C8 U3 is paired with a 501b XML T6 on my lid - both usually running on MED - and I often put another 501b XML T6 on my bars to use on HIGH as a boost light.
But as DIY says a lot of it is down to drivers.... the C8 U3 works for me because the MED mode is bright enough for long enough given the riding I typically do. If the MED mode was less bright it would be too dim, and if it were brighter the run time might start to be an issue (though I always carry a couple of spare cells).Vitus Sentier VR+ (2018) GT Grade AL 105 (2016)
Giant Anthem X4 (2010) GT Avalanche 1.0 (2010)
Kingley Vale and QECP Trail Collective - QECP Trail Building0 -
I posted a few months/pages back about this but never really figured out what I needed.
I have two of these lights:
http://www.ebay.co.uk/itm/1300Lm-CREE-X ... 4ab9370991
and they run of ~8v battery.
One of them works fine, The other has a knackered driver. Which I have confirmed my swapping the LED's around in the two lights.
I am just wondering what driver I can replace it with to get it working again. My broken one is marked LG-28 but googling this brings up nothing.
The two drivers most similar to the one I have taken out are:
http://dx.com/p/5v-8-4v-2000ma-3-mode-l ... ard-162787 and
http://dx.com/p/21-65mm-8-4v-1500ma-cir ... ore-166085
They are the same Ø boards and have the switch on the back. The only thing I am concerned about is that they are only 1.5A and 2A.. I gather that XML's can be driven to 3/3.5A pretty easily. Is this standard or is it likely to be less.(Meaning that the above drivers will be just as bright as my original?)
The other drivers I have found which look like they are capable of delivering3A are:
http://dx.com/p/5v-8-4v-2000ma-3-mode-l ... ard-162787 and
http://www.lightmalls.com/cree-xml-t6-8 ... cuit-board
Also just so I understand it a little more as I really don't have a clue what they do. In simple terms, is the driver used to control the total power (Watts?) going to the LED. So as the voltage in the battery goes down, it draws more current from it to keep W the same, keeping the LED at full brightness until the battery gets below a certain level, then it shuts down completely.
Does this mean a 4V battery / battery pack using a driver capable of delivering the same Amps as above give the same brightness, but as it has to draw more current to achieve this, it so it drains the battery sooner.
SHORT VERSION - Will any of the above 4 links fix my knackered light (Top link)0 -
No The driver maintains the current by doing two things. keeping the voltage constant as the input drops and micro switching the led on off on off at different frequencies.
4v in or 8v in makes no difference if the amps output are the same as the voltage out is constant.0 -
Sorry for all the stupid questions! When you say voltage in doesn't matter I take it that this only applies between the limits that the manufactures quote. Ie don't put 8v into a a driver which is designed for a maximum of 4v.
What sort of current and voltage do the drivers that usually come with the Chinese torches supply to the LED (When on the brightest mode) From what I have read about 3.7V and 2.5A is ideal.
Any reasons why this below wont be ok?
http://dx.com/p/5v-8-4v-2000ma-3-mode-l ... ard-1627870 -
Wast majority of XML-based lights aren't driving the LED at its maximum (mostly, due to the thermal management problems). Also, human perception of brightness is not linear - so, in simple words, chances are that these DX drivers will perform very close to your original one.bigdrew1 wrote:The only thing I am concerned about is that they are only 1.5A and 2A.. I gather that XML's can be driven to 3/3.5A pretty easily. Is this standard or is it likely to be less.(Meaning that the above drivers will be just as bright as my original?)
Exactly.Also just so I understand it a little more as I really don't have a clue what they do. In simple terms, is the driver used to control the total power (Watts?) going to the LED. So as the voltage in the battery goes down, it draws more current from it to keep W the same, keeping the LED at full brightness until the battery gets below a certain level, then it shuts down completely.
Absolutely correct, as long as capacity of both batteries are the same.Does this mean a 4V battery / battery pack using a driver capable of delivering the same Amps as above give the same brightness, but as it has to draw more current to achieve this, it so it drains the battery sooner.0 -
That isn't how I read the question. I read it that the question was does a 4v pack (e.g. 2P) connected to a 4v input driver drain quicker than an 8V pack (2S) connected to an 8v input driver for the same output. The answer is no.
My experience of the cheap drivers is that the output current is a factor of the input voltage. Which can be good and bad. One that has a variable input voltage should perform better though.0 -
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That's correct for scenario described above only: just because of substitution the battery with doubled capacity.diy wrote:I read it that the question was does a 4v pack (e.g. 2P) connected to a 4v input driver drain quicker than an 8V pack (2S) connected to an 8v input driver for the same output. The answer is no.0 -
capacity (Watts) is the same in both scenarios.0
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Watts is the unit for power, not capacity of a cell.diy wrote:capacity (Watts) is the same in both scenarios.0 -
Ok watt-hours - A cell-pack with 21Wh will power an XM-L consuming 2.5A for the same duration, no matter if it is running at 4.2v or 8.4v0
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Can anyone point me in the direction of a suitable charger for a 7.4v 4400mAh battery (4x188650) - I bought this by mistake (!) from DX a while back, want to use it so thought I'd try this out http://dx.com/p/fandyfire-d99-cree-xm-l ... ack-199471
but still need a suitable charger for the battery. I've searched the DX website without luck.
Edit - this is the battery pack http://dx.com/p/7-4v-4000mah-rechargeab ... lue-1555140 -
There really isn't enough detail to be certain. Some of the packs have the charge control on the pack, some just have basic protection.0
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Any 2s charger (typically, they're marked as "8.4v") will do. But be aware that most cheaper ones are often of inferior quality and might have reliability problems. Relatively good ones are made by MagicShine, but some rate of failures occurs with them, too. Some examples:Arthur Scrimshaw wrote:Can anyone point me in the direction of a suitable charger for a 7.4v 4400mAh battery
Noname:
http://www.ebay.com/itm/321093464378?
MS:
http://www.ebay.com/itm/321006076769
http://www.ebay.com/itm/270482162529
Also, your battery uses connector with 2.5mm central pin, while "de facto" standard for bike lights is 2.1mm one. Some chargers are "relatively compatible" with them (that is, you can insert the connector into battery's receptacle by applying some force); in other cases simple adapter is required.0 -
Go to DX, sort by price low to high. the expensive ones typically have over charge protection, the cheap ones don't. If you have a pack with over charge control then you can use a cheap Phase 2 charger.
http://dx.com/p/magicshine-0-8-lcd-8-4v ... ght-147199
doesn't seem to have charge control protection. So you would want to avoid using a cheap charger.
Whereas
http://dx.com/p/8-4v-3600mah-waterproof ... ack-201659
claims over charge protection.
Most of these cheap chargers deliver low amp phase 2 charge only, but I wouldn't want to do that on a pack without overcharge protection.0 -
All ready-to-use bike light lithium packs on DX are protected ones.diy wrote:Go to DX, sort by price low to high. the expensive ones typically have over charge protection, the cheap ones don't.
What is "Phase 2 charger"?If you have a pack with over charge control then you can use a cheap Phase 2 charger.
Why do you think so? :shock:http://dx.com/p/magicshine-0-8-lcd-8-4v-2200mah-18650-lithium-battery-cell-pack-for-bicycle-light-147199
doesn't seem to have charge control protection.
And the question remains: any example of bike light where charge control circuit is implemented in lithium battery pack, not in charger, please?0 -
http://batteryuniversity.com/learn/arti ... _batteries
see the different stages of charge, a lot of cheap chargers don't do stage 1. Not all protection circuits are the same, not all packs have overcharge protection. That is why they go pop.0 -
Any cheap charger will do stage 1. It is noted even in article you've linked.diy wrote:http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries
see the different stages of charge, a lot of cheap chargers don't do stage 1.
Well, let's return to the bike lights here. You've said there are lithium battery packs with embedded charge control, and there are packs without protection circuit. Where? Who made them? Any single example, please!not all packs have overcharge protection.0 -
Anything with low mA output is not going to do stage 1 very well. There are plenty for sale - irrelevant of what is printed on the "CE approved label" which is often a work of fiction. You also cannot be sure of the protection in the pack based on what is advertised. I Personally would not charge an unknown 4 pack with a cheap charger. Simple as that.
See these:
http://dx.com/p/8-4v-3000mah-rechargeab ... ack-182591
http://dx.com/p/magicshine-0-8-lcd-8-4v ... ght-147199
what protection do they have from the info?0 -
What do you mean? Stage 1 is supplying the current to the battery until it reaches specified voltage level: particular mA and battery capacity affect just the time reqired for that.diy wrote:Anything with low mA output is not going to do stage 1 very well.
Industry standards do not allow assembled lithium batteries without protection to be supplied to the consumer market. Even your cellular phone's battery does have it onboard. Of course, nothing is 100% reliable, but that's different story...You also cannot be sure of the protection in the pack based on what is advertised.
They both have standard protection circuits installed. And concerning the info - I'd highly recommend not to use item descriptions from various Chinese "We sell everything!"-style web shops as a source of technical information.See these:
http://dx.com/p/8-4v-3000mah-rechargeab ... ack-182591
http://dx.com/p/magicshine-0-8-lcd-8-4v ... ght-147199
what protection do they have from the info?0 -
Had an email from Lighmalls offering me this fantastic deal
http://www.lightmalls.com/sky-ray-7t6-b ... attery-set
Maybe if I strap on 3 extra battery packs it might run it. It would also keep me nice and warm in the middle of the cold winter...
Go on Archie, you know you want to try one... Although technically it might be my turn to waste some money on a light we all know will be useless... 0 -
Its got to be worth a punt just for the novelty factor. I wonder if you'd actually notice the extra light above a 5 LED unit. 7 LEDs powered by 6 cells is not going to last long.0
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Let's see. It depends from particular driver's circuit, and I've seen very different samples from East...diy wrote:I wonder if you'd actually notice the extra light above a 5 LED unit.
Sure. This is why I'm waiting for "head only" option: there's no reasons to order yet another piece of junk.7 LEDs powered by 6 cells is not going to last long.0 -
A tad unseasonal,but just found this regarding fake 18650 batteries,turns out you can buy heat shrinks labels for just about any battery brand,all the more reason to salvage them.
http://budgetlightforum.com/node/149620
