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Is there any good non-rechargeable headlights anymore?
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#42
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Is there any good non-rechargeable headlights anymore?
On Fri, 12 May 2017 08:51:55 +0700, John B.
wrote: On Thu, 11 May 2017 09:17:40 -0700, Jeff Liebermann wrote: On Thu, 11 May 2017 04:03:29 -0700 (PDT), wrote: If the OP uses 4 1.5V Lion in a parallel batt carrier wired in series to a second same carrier the V is 3.0 3 in series is 4.5V Correct ? No. Most (not all) LiIon cells are a nominal 3.7V. Plug one of these into something made for a 1.5v akaline battery and you will have a smoking ruin. This is a very real problem. I have several flashlights that use 14500 LiIon cells which are exactly the same size as a AA battery. If I accidentally plug one of these into a AA battery holder, it will probably destroy the device. So in potential possibility repairing a failed proprietary integral batt device is possible. Nope. Plugging in the wrong battery does not make things go better or fix them. I have 2 devices, a Pioneer 2DIN receiver and a new Amprobe 510 multimeter asking connect to ground first. I had operated under the auto batt standard of grounD last. Is this a current sea change ? No. It is also wrong. In a car, I'm told that you connect the ground (negative) battery terminal last. That's because when you tighten the positive battery terminal with an un-insulated wrench, and you accidentally hit the grounded chassis or grounded battery frame, if the ground (negative) terminal is disconnected, there will be no spark, arc, smoke, or exploding battery. Of course, grounding the ground lead with a wrench will not do anything dangerous. Unless you have a classic car, such as a pre '60's Volkswagen, many British cars prior to the '60's, or even a Ford, from the Model A through about 1948, all of which had positive grounds :-) Also, pre-1960's White and Mack trucks had positive grounds. The logic is fairly simple. Positive ground reduces corrosion effect. However, I have a different theory. Look at the polarity for a DC stick arc welder. Worktable ground is positive. If you build cars and trucks with an arc welder, then a positive ground would seem logical. Or it might have been intentionally different in an attempt at "product differentiation" which means you need to buy special accessories for a positive ground car[1]. "THE ARGUMENT FOR POSITIVE GROUND" http://lajagclub.com/the-argument-for-positive-ground/ Long ago, I stopped to help a lady start her sports car (forgot the model) by jump starting it. My car was negative ground and hers was positive. No problem as long as nothing conductive gets between the bodies of the two cars. We got to talking and not paying attention. Her car door hit mine. Sparks, smoke, etc. I had the good sense to kick the doors apart to prevent welding the cars together. Standards are a good thing. It doesn't matter which polarity electrical system is used. One connects the hot battery terminal first, and the grounded terminal last. [1] I used to be in the 2-way radio biz. During the 1960's most 2-way radios came with a floating ground, where it would work with either a negative or positive ground system. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
#43
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Is there any good non-rechargeable headlights anymore?
On 5/11/2017 4:52 PM, Joerg wrote:
NiMH can deliver a lot more peak current. I had a Duracell 4C flashlight that I got at Costco. It came with Duracell alkaline batteries. I put in four NiMH batteries and it destroyed it. I put int two NiMH and two alkaline and it was fine. I put in three NiMH and one alkaline and it destroyed it. Clearly they were depending on the high internal resistance of alkaline batteries to regulate the current to the LED. Fortunately it was Costco so they gave me no trouble returning two of them. Depending on the internal resistance of batteries to limit current is a very lame design. There was no warning on the packaging to not use NiMH cells. |
#44
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Is there any good non-rechargeable headlights anymore?
On 2017-05-12 10:29, sms wrote:
On 5/11/2017 4:52 PM, Joerg wrote: NiMH can deliver a lot more peak current. I had a Duracell 4C flashlight that I got at Costco. It came with Duracell alkaline batteries. I put in four NiMH batteries and it destroyed it. I put int two NiMH and two alkaline and it was fine. I put in three NiMH and one alkaline and it destroyed it. Clearly they were depending on the high internal resistance of alkaline batteries to regulate the current to the LED. Fortunately it was Costco so they gave me no trouble returning two of them. Depending on the internal resistance of batteries to limit current is a very lame design. There was no warning on the packaging to not use NiMH cells. Yep, classic problem. That was a dirt-cheap "design" or in harsher words a junk product. I'd return that for a full refund. I was amazed what 18650 Li-Ion can do. When removing an old bicycle battery I accidentally slipped with the screwdriver and shorted the contacts of a 2-series combination that was at most 50% charged. BZZZZTTT ... PHUT ... *POOF* and the metal contact tongue had evaporated itself, emitting a bright white light for a split second. Completely gone. -- Regards, Joerg http://www.analogconsultants.com/ |
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Is there any good non-rechargeable headlights anymore?
On Wednesday, May 10, 2017 at 11:08:42 PM UTC-5, Jeff Liebermann wrote:
On Wed, 10 May 2017 20:21:11 -0700 (PDT), Andy wrote: You might want to ignore bicycle lights per se and be creative. :-) There are many flashlights that meet you light needs. One produces 1000 lumens. Please pardon my scepticism. The typical white LED belches about 75 lumens/watt when warm. Therefore, this flashlight will requi 1000lumens / 75lumens/watt = 13.3 watts to operate. A 10 watt LED looks like these: https://www.google.com/search?q=10+watt+led&tbm=isch and usually requires a rather large heat sink like these: https://www.google.com/search?q=10+watt+led&tbm=isch Seen any flashlights with such an LED or heat sink (or fan)? Of course, one can use smaller LED's to produce a 13.3 watt array. The typical 2watt LED would requires 7 LED's to produce the 1000 lumens. Seen any flashlights that have 7 LED's? 10 watts also requires quite a bit of battery current. Assuming a single 18650 cell, that's about: 10 watts / 3.7 volts = 2.7 amps At 2 amps (the best data I could find), an 18650 cell will deliver about 7 watt-hrs: http://www.lygte-info.dk/pic/Batteries2011/All18650/Energy-2A.png Extrapolating to 2.7A, I would guess(tm) about 5.5 watt-hours. Therefore, a single 18650 cell will last: 5.5 watt-hrs / 2.7A = 2 hrs which is actually quite good. The cheap junk 18650 cells that I like to use (because they're cheap), measure about 700 ma-hrs at 2.7A. That would give me: 3.7v * 0.7Amp-hrs / 2.7A = 1 hr (approx). And they are way cheaper. Cheap is good. Cheaper is better than good. All it takes to mount them are 2 adjustable clamps. Most easily removable adjustable handlebar clamps that I've tried are horrible. They all slip or vibrate badly. As long as headlight manufacturers insist that the rider must be able to install and remove the clamp without tools, they're going to continue to slip. Use NiMh batteries. Use Eneloop or LSD (low self discharge) NiMH batteries, or you will find yourself with dead batteries in the middle of the ride from self discharge. I made a light system using a SLA battery that was as bright as a car headlight. Sigh. Megalumens again. Do you really need something as bright as a car headlight (700 lumens low, 1200 lumens high)? Do you enjoy blinding oncoming traffic and other cyclists? -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 You are just full of criticism. Reminds me of know it alls. :-) Andy |
#46
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Tim the Tool Man, Needs More POWER
On 5/10/2017 11:08 PM, Jeff Liebermann wrote:
On Wed, 10 May 2017 20:21:11 -0700 (PDT), Andy wrote: ... I made a light system using a SLA battery that was as bright as a car headlight. Sigh. Megalumens again. Do you really need something as bright as a car headlight (700 lumens low, 1200 lumens high)? Do you enjoy blinding oncoming traffic and other cyclists? There used to be a guy on Bikeforums (hope it wasn't Andy) ANY time people asked about lights, he would post pictures of his setup, and brag about how he could see stuff on the ground 50 yards away at night. He could easily see reflective road signs 200+ yards away. The comedy of this was that this person was very-late-middle-aged, somewhat overweight (like myself) and rode a upright "granny" trike. The battery may not have been SLA but it was about as big as a motorcycle battery, and it had to be carried in the rear basket because it was too big to easily mount anywhere else. I couldn't help but wonder: how fast do you think that guy EVER rides? Probably not very much so, I'd think. Why did he need a 50-watt xenon headlight on his trike? I dunno, but he thought it was AWESOME. ....For some reason he was never able to explain well, he thought that having this huge front light greatly improved his safety, with regards to being seen by cars. ??? I think I annoyed him once when I said that he should put a red lens on it and mount it on the *rear*, since any oncoming cars should be driving on the OPPOSITE side of the road, and the greater risk was being hit from /behind/, , , , -but that was dumb for some reason I forget. He had a reason. I don't remember. -------- Now... I've heard of people who MTB at night, and I can understand that being a reason to want as much light as possible for that. (I can't MTB at night in the central USA, as there is one billion spiderwebs strung across every 10-yard stretch of wooded trails at night) ....And I can understand people having vision problems, and a lot of light might help for that. ....But I never understood the reason for overspending for a high-power light setup, especially for people who are (almost certainly) very casual pavement-only riders. If I could pay ~$45 each and replace the ruined 4xAA Cateyes with the same ones but new, I'd do it in a heartbeat. |
#47
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Is there any good non-rechargeable headlights anymore?
Andy.
we have several well known experts here n Lieb is one. here you read riders worked up abt bike lights. Read the Beattie Hub Generator Tales. The bike light league is prob 100,000 strong. Commercial market generating bike lights no longer even remotely linked to flashlight but that light is emitted. Flashlights are candles. when a group rides by at night n there's one good setup the lighting just knocks your socks off. |
#48
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Tim the Tool Man, Needs More POWER
On 5/12/2017 5:36 PM, DougC wrote:
On 5/10/2017 11:08 PM, Jeff Liebermann wrote: On Wed, 10 May 2017 20:21:11 -0700 (PDT), Andy wrote: ... I made a light system using a SLA battery that was as bright as a car headlight. Sigh. Megalumens again. Do you really need something as bright as a car headlight (700 lumens low, 1200 lumens high)? Do you enjoy blinding oncoming traffic and other cyclists? There used to be a guy on Bikeforums (hope it wasn't Andy) ANY time people asked about lights, he would post pictures of his setup, and brag about how he could see stuff on the ground 50 yards away at night. He could easily see reflective road signs 200+ yards away. The comedy of this was that this person was very-late-middle-aged, somewhat overweight (like myself) and rode a upright "granny" trike. The battery may not have been SLA but it was about as big as a motorcycle battery, and it had to be carried in the rear basket because it was too big to easily mount anywhere else. I couldn't help but wonder: how fast do you think that guy EVER rides? Probably not very much so, I'd think. Why did he need a 50-watt xenon headlight on his trike? I dunno, but he thought it was AWESOME. ...For some reason he was never able to explain well, he thought that having this huge front light greatly improved his safety, with regards to being seen by cars. Sounds like Mr. Scharf. -- - Frank Krygowski |
#49
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Is there any good non-rechargeable headlights anymore?
On 5/10/2017 9:08 PM, Jeff Liebermann wrote:
Most easily removable adjustable handlebar clamps that I've tried are horrible. They all slip or vibrate badly. As long as headlight manufacturers insist that the rider must be able to install and remove the clamp without tools, they're going to continue to slip. This is true. But those clamps are cheap. For flashlights I make my own. http://www.dx.com/p/motorcycle-bike-handlebar-clamp-bottle-holder-adapter-silver-447307 https://www.amazon.com/dp/B000056BMU (AA) or https://www.amazon.com/dp/B000056BMV Aluminum flat bar Bolts and lock nuts Heat shrink tubing Thead lock compound. http://nordicgroup.us/s78/images/IMG_0239.JPG http://nordicgroup.us/s78/images/IMG_0303.JPG |
#50
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Is there any good non-rechargeable headlights anymore?
Asked an experienced truck the multimeter question n he gave the exact spell as Lieb including a sign off when asked to relate Ford's system to ....
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