Eyc headlight problem

On Sunday, March 28, 2021 at 6:08:50 p.m. UTC-4, Frank Krygowski wrote:
On 3/28/2021 1:01 PM, Jeff Liebermann wrote:
On Sun, 28 Mar 2021 11:40:08 -0400, Frank Krygowski
wrote:

I tried the switch (and I do
dislike "soft" switches buried under rubber covers), I felt the wiring
connections, spun the wheel a few times, then it came back on. Rode ten
feet and it blinked off. Then back on and stayed on, mostly, but would
occasionally blink off then back on.

At one stop to listen to a chorus of frogs, the Eyc was running only its
standlight when it suddenly blinked off. That tells me it's not a wiring
connection or an internal dyno problem. It must be a problem inside the
headlamp itself. Also, it's not triggered by bumps AFAICT, and it
sometimes blinked off while riding a perfectly smooth surface.

Fortunately, it always came back to life and for the rest of the 15 mile
ride it blinked out only occasionally, and for never more than a second.
But its very worrisome.

I've seen similar symptoms with LiIon flashlights and battery powered
bicycle lighting. My guess(tm) is a loose connection somewhere in the
wiring system. As you mention, it could also be inside the light. The
erratic intermittent behavior suggests that it's NOT an electronics
component failure, which would be more cyclic.

Most commonly (in flashlights), I see this caused by the LED COB. The
LED is soldered onto the PCB (printed circuit board) forming the COB
(chip on board). The PCB will flex as the LED heats up eventually
breaking the solder connection. The solder doesn't really melt, but
instead cracks. I fix these using a hot air SMD soldering station:
https://www.google.com/search?q=hot+air+smd+rework+station&tbm=isch
Tear the light apart, and touch the LED or slightly bend the PCB while
the lamp is operating. If it flickers, you found the problem. It can
also be components other than the LED, which should be detectable by
bending the PCB or visual inspection. Using the SMD soldering station
takes practice. I suggest you find someone who knows how to use one.

Another problem I've seen are crappy wire connections. These come in
a variety of failures such as cold solder connection, bad crimp,
insulation displacement, jacket creep, and corrosion. The best way to
find these is by probing with a DVM (digital volt meter). The catch
is that you can only find a bad connection if the light is in failure
mode. If it seems to be working normally on the workbench, you're
probably better off taking the light and wiring apart and pulling on
each connection. If the connection moves, stretches, or falls apart,
you found the problem. Corrosion should be obvious. Also, look for
annual rings (usually black) around wires that run through holes in
the PCB. Such rings are cold solder joints, caused by the assembler
being in a hurry, and need to be restarted.

I've only seen one broken wire on a bicycle, which took me weeks to
isolate. I finally found it by pulling on each of the wire ends. One
wire seemed to stretch, indicating a break somewhere. I found where
the insulation necked down from the stretching and spliced the wire.
Problem solved. This wire was NOT under tension and showed no sign of
corrosion, so my guess(tm) is that the wire was defective from the
vendor.

However, my initial wild guess points to the Union bottle dynamo. I
haven't seen any failures with these because I don't use them.
However, if it's as old as you suggest, it might be a good place to
start. Try powering the light with a battery or power supply. Then,
disconnect one of the power wires. The B&M lights usually have a
stand light feature, which is basically a supercap to power the LED
while the generator is NOT turning. If you disconnect the power wire,
and the light goes into stand light mode, and slowly fades away, then
it's working normally. Therefore, the problem is likely NOT in the
dynamo or wiring that power the light. I would need to be after the
stand light circuitry inside the B&M light.

Good luck.

Drivel:
https://phobia.wikia.org/wiki/Dizoangphobia
https://phobia.wikia.org/wiki/Electrophobia
https://phobia.wikia.org/wiki/BMWphobia
https://phobia.wikia.org/wiki/Cyclophobia
Thanks for the information. I've emailed Peter White and will say what
he says before I dig in further.

But as I said, I suspect the problem is internal to the headlamp because
one of the time it shut down, I was stationary. The light was in
standlight mode, during which it gets no external current supply. The
standlight turned off just as suddenly as the main light was doing.

But again, thanks. (I'm hoping that on the bench, powering this with a
6VDC battery should be as valid as powering it with a dynamo.)

--
- Frank Krygowski

Could it be that a faulty sensor is registering something as getting too hot and shutting down even if for a second or so?

Cheers

Am 29.03.2021 um 06:22 schrieb Sir Ridesalot:
On Sunday, March 28, 2021 at 6:08:50 p.m. UTC-4, Frank Krygowski wrote:

But as I said, I suspect the problem is internal to the headlamp because
one of the time it shut down, I was stationary. The light was in
standlight mode, during which it gets no external current supply. The
standlight turned off just as suddenly as the main light was doing.

But again, thanks. (I'm hoping that on the bench, powering this with a
6VDC battery should be as valid as powering it with a dynamo.)

Could it be that a faulty sensor is registering something as getting too hot and shutting down even if for a second or so?

More likely a loose element (broken soldering point) on the IC.
At some tail lights, it tended to be the capacitor that broke loose;
I've never heared of it happening to front lights as well.

Rolf

Frank Krygowski wrote:

But again, thanks. (I'm hoping that on the bench, powering this with a
6VDC battery should be as valid as powering it with a dynamo.)

Not the AC-Eyc, RTFM.

But how about a new lamp and some real circuit?
http://tandem-fahren.de/Mitglieder/Framstag/LED/Wollmilchsau/

On Mon, 29 Mar 2021 12:23:28 +0200, Sepp Ruf
wrote:

Frank Krygowski wrote:

But again, thanks. (I'm hoping that on the bench, powering this with a
6VDC battery should be as valid as powering it with a dynamo.)

Not the AC-Eyc, RTFM.

That was my suggestion. I assumed that anything with a bridge
rectifier on the AC input would also run on DC.

Nothing in the data sheet:
https://www.bumm.de/en/products/dynamo-scheinwerfer/produkt/160rtsndi%20.html

However, the instructions say otherwise:
https://www.bumm.de/files/Produkte/LUMOTEC%20Eyc_Avy_IQ-XS.PDF
The headlight can only be powered by a dynamo (AC). Connection
to a DC power source (battery) is not possible.

I don't have a schematic or headlight to dissect. I wonder what
they're doing to prevent DC operation.

There is a 6 to 42VDC Eyc version:
https://curbsidecycle.com/products/busch-muller-lumotec-eyc-dc-front-light-e-bike
which probably has a different DC-DC buck converter. I couldn't find
this DC version on the B&M site, but did find this:
https://www.bumm.de/en/products/e-bike-beleuchtung.html?info=1
In Germany before 2014, e-bikes had to have a regular
bicycle dynamo powering the light system. Such a dynamo
supplies 6 VC AC. If your e-bike is equipped with a
dynamo, it is not suitable for use with an e-bike headlight.
All our dynamo-powered headlights may be used in this case.

I'm suspicious that this is a safety measure inspired by users
connecting the AC dynamo version of the headlight to an eBike with a
12, 26, or 48 VDC battery and destroying the headlight. Nobody makes
a 6VDC eBike making the risk quite real. However, to be safe and in
case I missed something, I won't suggest that Frank plug his Eyc into
a 6VDC battery.

Peter White Cycles nothing about battery power in the Eyc section at:
https://www.peterwhitecycles.com/b&m-hl.php
but does have a note about running the IQ-X on 5VDC from USB power.
We have recently discovered, (April 19, 2017) that the
IQ-X headlight and the Busch & Müller USB-WERK charger
are not compatible. When the cache battery in the
USB-WERK is charging, the IQ-X beam becomes quite dim.
While riding, this can happen for about two seconds,
every thirty seconds or so, and so causes a dangerous
situation, since the rider will briefly not be able to
see the road ahead. If you have the USB-WERK and plan
to use the IQ-X headlight, you should be prepared to
unplug the USB-WERK at night. I recommend using the
Lumotec IQ CYO Premium T Senso Plus or the new IQ-XS
with the USB-WERK, since they are unaffected by this.

My guess(tm) is the IQ-X lights require the peak AC voltage
(6VAC * 1.414 = 8.5V) to operate at full brightness or the charging
current causes a voltage drop to below the IQ-X operating point. The
Eyc might have a similar problem.

But how about a new lamp and some real circuit?
http://tandem-fahren.de/Mitglieder/Framstag/LED/Wollmilchsau/

Google translate did a good job of translating the German into
English. I can't resist looking at the circuit but have only 15
minutes.

Looks like you may have confirmed my low voltage theory:
The Busch + Müller IQ-X E that was evaluated first turned
out to be unusable in the dynamo emergency mode:
up to 20 km / h it remains quite dark and above it
flickers at approx. 1 Hz.
Congrats, you created a relaxation oscillator.

- I don't see an over or under voltage protection (battery management
system) for the LiIon cells on the schematic. However, there's one in
the photo of the red 18650 cells and mentioned in the text. However,
the BMS mentioned in the text is not available in 2S.

- If the red colored 18650 cells in the photo are from "GTL", I have a
few and they are junk. The Samsung cells are much better.

- I don't see the usual resistive divider and timing capacitors on the
555 chip (U2).

- Do you have a LUX meter? If so, I have a lumens measuring
experiment I would like to have you try. Details later.

Thanks, good luck, and I'll be back with more tomorrow.

--
Jeff Liebermann
PO Box 272 http://www.LearnByDestroying.com
Ben Lomond CA 95005-0272
Skype: JeffLiebermann AE6KS 831-336-2558

Jeff Liebermann wrote:
On Mon, 29 Mar 2021 12:23:28 +0200, Sepp Ruf wrote:
Frank Krygowski wrote:

But again, thanks. (I'm hoping that on the bench, powering this with a
6VDC battery should be as valid as powering it with a dynamo.)

Not the AC-Eyc, RTFM.

That was my suggestion. I assumed that anything with a bridge
rectifier on the AC input would also run on DC.

It's tempting, I know.

But how about a new lamp and some real circuit?
http://tandem-fahren.de/Mitglieder/Framstag/LED/Wollmilchsau/

Google translate did a good job of translating the German into
English. I can't resist looking at the circuit but have only 15
minutes.

Looks like you may have confirmed my low voltage theory:

Hold on, Jeff, I'm sorry for the little misunderstanding. I only linked to
Ulli Horlacher's latest work there, presented at de.rec.fahrrad on Fri, 26
Mar 2021 08:06:31 +0000 (UTC). Actually, I do not even agree with the
concept of basing one's entire front lighting on one, single beam lamp,
however expensive and reliable it may be.

On 3/29/2021 10:41 AM, Jeff Liebermann wrote:

snip

I don't have a schematic or headlight to dissect. I wonder what
they're doing to prevent DC operation.

I've seen buck/boost converters with an AC input though the AC frequency
from the dynamo would appear to be way too low to be efficient.

Perhaps they say that you can't operate it from DC either because of the
additional losses through the rectifier or because they wanted to ensure
that it isn't hooked up to a 12V or higher electrical system.

What's useful for testing dynamo lights is a 6V filament transformer
i.e. https://www.aliexpress.com/item/4001271812376.html, or a Variac.

On 3/29/2021 5:02 PM, Sepp Ruf wrote:

snip

Hold on, Jeff, I'm sorry for the little misunderstanding. I only linked to
Ulli Horlacher's latest work there, presented at de.rec.fahrrad on Fri, 26
Mar 2021 08:06:31 +0000 (UTC). Actually, I do not even agree with the
concept of basing one's entire front lighting on one, single beam lamp,
however expensive and reliable it may be.

Most people in the U.S. with dynamo lights (and there aren't a lot of
them!) also have some sort of battery powered light, even just an
inexpensive USB-rechargeable light.

One reason is to have a backup, but the main reason is that most dynamo
lights don't have a flash DRL mode because that mode isn't legal in some
European countries where most of the dynamo lights are sold. I suspect
that's why Frank bought the Oculus from Barry Beams, even though he'd
never admit it. The only dynamo light I've seen with a flash mode is the
Planet Bike Blaze Dynamo, a pretty low-power light
https://www.planetbike.com/blaze-dynamo-sl-bike-headlight/.

I designed a simple circuit to use on dynamo lights, with no DRL but
with a lower-intensity stand-light, to add DRL functionality . It
disconnects and reconnects the AC voltage from the dynamo so the light
goes between full brightness and standlight brightness (this is similar
to the "breathe mode" on some battery powered lights).

On Tuesday, March 30, 2021 at 1:59:57 PM UTC-5, sms wrote:
On 3/29/2021 5:02 PM, Sepp Ruf wrote:

snip
Hold on, Jeff, I'm sorry for the little misunderstanding. I only linked to
Ulli Horlacher's latest work there, presented at de.rec.fahrrad on Fri, 26
Mar 2021 08:06:31 +0000 (UTC). Actually, I do not even agree with the
concept of basing one's entire front lighting on one, single beam lamp,
however expensive and reliable it may be.
Most people in the U.S. with dynamo lights (and there aren't a lot of
them!) also have some sort of battery powered light, even just an
inexpensive USB-rechargeable light.


I have a dynamo powered light on one bike. Busch Mueller LED lights. And I have a Princeton Tec AAA battery powered light on my helmet at all times.





One reason is to have a backup, but the main reason is that most dynamo
lights don't have a flash DRL mode because that mode isn't legal in some
European countries where most of the dynamo lights are sold. I suspect
that's why Frank bought the Oculus from Barry Beams, even though he'd
never admit it. The only dynamo light I've seen with a flash mode is the
Planet Bike Blaze Dynamo, a pretty low-power light
https://www.planetbike.com/blaze-dynamo-sl-bike-headlight/.

I designed a simple circuit to use on dynamo lights, with no DRL but
with a lower-intensity stand-light, to add DRL functionality . It
disconnects and reconnects the AC voltage from the dynamo so the light
goes between full brightness and standlight brightness (this is similar
to the "breathe mode" on some battery powered lights).

On 3/30/2021 2:59 PM, sms wrote:
On 3/29/2021 5:02 PM, Sepp Ruf wrote:

snip

Hold on, Jeff, I'm sorry for the little misunderstanding.* I only
linked to
Ulli Horlacher's latest work there, presented at de.rec.fahrrad on
Fri, 26
Mar 2021 08:06:31 +0000 (UTC).* Actually, I do not even agree with the
concept of basing one's entire front lighting on one, single beam lamp,
however expensive and reliable it may be.

Most people in the U.S. with dynamo lights (and there aren't a lot of
them!) also have some sort of battery powered light, even just an
inexpensive USB-rechargeable light.

I very much doubt that statement arose from anywhere but your
imagination. You can't possibly have data to back it up.

It's true there aren't a lot of U.S. cyclists with dyno lights. That's
mainly because there aren't a lot of U.S. cyclists who use their bikes
as anything but toys and exercise machines. There isn't the critical
mass to form a target market for a light that's always available at the
flick of a switch plus gives far better illumination than almost all
battery lights.

One reason is to have a backup, but the main reason is that most dynamo
lights don't have a flash DRL mode because that mode isn't legal in some
European countries where most of the dynamo lights are sold. I suspect that's why Frank bought the Oculus from Barry Beams, even though he'd
never admit it.

No, Steve. I bought the Oculus because I was curious especially about
the optical design after it was discussed here pretty extensively; and I
could easily afford it. I'll admit, I did expect to be able to resell it
fairly easily, and that hasn't been true. (I've never bothered to get
into Ebay sales. Perhaps I should.)

The only dynamo light I've seen with a flash mode is the
Planet Bike Blaze Dynamo, a pretty low-power light
https://www.planetbike.com/blaze-dynamo-sl-bike-headlight/.

Flashing headlights are just the latest gimmick for the paranoid. They
go with horizontal or vertical flags on the back of the bike, big thick
hats, garish colored clothing, electric horns, turn signals and probably
a dozen other "safety" talismans.

Lots of cultures have good luck talismans.
https://www.invaluable.com/blog/good-luck-charms/
Flashing lights are for bike culture.

--
- Frank Krygowski

On Tuesday, March 30, 2021 at 7:29:29 PM UTC-7, Frank Krygowski wrote:
On 3/30/2021 2:59 PM, sms wrote:
On 3/29/2021 5:02 PM, Sepp Ruf wrote:

snip

Hold on, Jeff, I'm sorry for the little misunderstanding. I only
linked to
Ulli Horlacher's latest work there, presented at de.rec.fahrrad on
Fri, 26
Mar 2021 08:06:31 +0000 (UTC). Actually, I do not even agree with the
concept of basing one's entire front lighting on one, single beam lamp,
however expensive and reliable it may be.

Most people in the U.S. with dynamo lights (and there aren't a lot of
them!) also have some sort of battery powered light, even just an
inexpensive USB-rechargeable light.
I very much doubt that statement arose from anywhere but your
imagination. You can't possibly have data to back it up.

It's true there aren't a lot of U.S. cyclists with dyno lights. That's
mainly because there aren't a lot of U.S. cyclists who use their bikes
as anything but toys and exercise machines. There isn't the critical
mass to form a target market for a light that's always available at the
flick of a switch plus gives far better illumination than almost all
battery lights.

That's total nonsense. Pre-pandemic, I rode with dozens or hundreds of commuters every day, probably one out of thirty had a dyno -- if even that. People prefer brighter, battery powered lights. Every time I hear your story of cohorts admiring your bright light, I think WTF? I've got SP PD8 dyno hub driving a Luxos B, and its inadequate for night riding anywhere other than lighted streets. Its nice having the dyno when all else fails, but it is not a serious primary light on the roads and in the weather I ride. And yes, I ride with a battery "flasher" -- an L&M that pulses. It differentiates my solid beam from other solid beams, vis., cars and other bikes in two way facilities.

-- Jay Beattie.