On Tue, 30 Jun 2020 04:32:31 -0700, sms
wrote:
On 6/29/2020 8:37 PM, Jeff Liebermann wrote:
On Mon, 29 Jun 2020 15:42:39 -0700, sms
wrote:
Another CCFL that makes a decent bicycle light (sorry Frank!):
Huh? CCFL is a Cold Cathode Fluorscent Light. The few I've seen are
either for colorful accent (visibility) bicycle lighting, or in an
automotive "halo ring" that seems more decorative than useful.
Something like this for a Mazda:
https://www.ebay.com/itm/CCFL-Angel-Eye-Halo-Light-Ring-7000K-White-LED-Headlight-For-MAZDA-3-Sedan-PZ-/263752283408
What you found on Amazon seems to be an LED flashlight. It even says
so in the description:
"High Lumen LED chip delivers so much light..."
Am I missing something here?
Yes. I didn't want to spell it out as I think those that coined the
phrase are insensitive. I prefer, "Inexpensive Flashlight Manufactured
in China."
You might want to amend your original posting and change the CCFL to
LED.
? https://www.amazon.com/dp/B07MP9RTHM
Note the lack of any specifications for Lumens, beamwidth, StVZO/TA
compliance, etc.
Yes. I think that the fact that they aren't making absurd lumen claims
is a good thing. All they'll say is that the LED they use is rated at
800-1000 lumens. The EU apparently now has a "useful lumens" standard.
I presume that you believe that no specifications are an improvement
over inflated specifications. Well, that does offer considerable
maneuvering room between these extremes, but doesn't really help the
buyer determine the brightness of the light. Quite often, the same
offshore manufacturers inflate their numbers for lumens, but fail to
do so for current drain and battery life. Based on an average 100
lumens per watt efficiency, I can usually make a tolerable guess(tm)
as to the lumens output (minus the lens losses). The lack of any
specifications in the Amazon web page makes that impossible. However,
not to worry. I've been told in this very newsgroup that lumens are
not important and that beam pattern is what determines quality.
Perhaps you can convince the Amazon vendor into providing an inflated
beam pattern claim?
It's pretty rare these days to find a 3x AA light, a lot of the lights
use 3 AAA batteries which is not desirable.
True. After the 1.5V AA alkaline batteries are depleted, some users
plug in three 16500 LiIon cells at 3.7V each, and blow up the
flashlight light.
Oops. That should be a 14500 LiIon cell.
I can't imagine that happening much since 16500 Li-Ion cells are not
something the average consumer would ever buy.
They're being offered for sale all over eBay and Amazon:
https://www.ebay.com/sch/i.html?_nkw=Li-Ion+14500+battery
I've also repaired 3 such AA (14500) cell flashlights mostly be
replacing the AMC7135 current regulator chips. It's probably not a
common way to destroy a flashlight, but it happens. It also might be
a good reason why flashlight vendors are hesitant to supply AA
holders, while flashlights made for battery vendors have no such
hesitation.
The ability to use an 18650 battery is nice because these are much more
widely available than a 26650 battery.
I try to buy flashlights that fit 26550 cells because I can get a
cheap adapter sleeve to also fit an 18650 cell.
https://www.ebay.com/sch/i.html?_nkw=26650+to+18650+adapter
The diameter of a 26650 cell is smaller than the 3AA adapter or the
18650 adapter that came with this flashlight. It works without it, but I
worried about rattling so I put in a spacer so it fits snugly.
Good point. The Amazon page says the OD (outside diameter) of the
light is 30 mm. The 26650 cell is 26 mm wide, leaving about 1 or 1.5
mm for the flashlight wall thickness. With 3 AA batteries, I
determined that they will fit into the 1 1/4" (31.75 mm) hole in an
ancient RapiDesign large circle template.
https://www.google.com/search?q=RapiDesign+large+circle+template&tbm=isch
I can do the trig if you want, but a circle template is easier and
quicker. There's no way a 32 mm dia three cell bundle is going to fit
into a 27 mm hole. 27 mm is about 1" diameter and my three cell AA
blundle doesn't come close to fitting into a 1" hole.
My guess(tm) is that the Amazon flashlight in question actually uses
three AAA cells.
There is such a thing as a three AA battery holder:
https://www.aliexpress.com/item/33010330793.html
Notice the OD of the battery holder is 30 mm, which is also the OD of
the flashlight. Unless the flashlight body were infinitely thin,
that's not going to work.
The real issue is finding protected 26650 cells that are accurately
rated. I haven't purchased these
https://www.orbtronic.com/26650-battery-protected-li-ion but from what
I read they actually test slightly higher than their rating. I saw that
the Oculus lights used 4500mAH 26650 cells which were probably the
highest capacity available when that light was introduced.
Accurately rating a LiIon cell is a bit of a challenge. Do you use
the industry de facto standard of measuring the discharge rate at
0.2C, which is useless for a flashlight that often operates at 1C or
more? If I wanted to see accurate capacity ratings, I would like to
see them tested at the operating current of the flashlight (and at
various temperatures), which means that the numbers need to come from
the flashlight vendor. Since they usually don't include batteries
with their flashlights, they usually ignore such a test. To their
credit, the high end bicycle light makers do supply batteries with
their lights, and usually supply accurate numbers.
"Everyone lies, but that's ok because nobody listens". (Nick Diamos)
--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060
http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558