dynamo lighting

  • Thread starter Zebee Johnstone
  • Start date



On Sun, 12 Mar 2006 14:16:34 +1100, Terry Collins wrote:

> No, no, no. Stay well away from Tony's site. You will end up spending
> valuable bicycle funds on lighting project. {:).


Yeah, my site's so much safer for your funds. Oh wait...

http://hired-goons.net/lights/

--
Dave Hughes | [email protected]
"Two of my imaginary friends reproduced once ... with negative results."
- Ben, ASR
 
Zebee Johnstone wrote:
> In aus.bicycle on Sat, 11 Mar 2006 13:44:18 +1100
> Random Data <[email protected]> wrote:
>
>>On Sat, 11 Mar 2006 01:58:11 +0000, Zebee Johnstone wrote:
>>
>>
>>>Anyone got any idea where I can get 6v halogen bulbs? Not MR16 lights,
>>>but bulbs, similar to Jaycar SL2722 but 6v?

>>
>>Rare as hen's teeth, and generally expensive, depending on exactly what
>>you're after. Stick with 12V. P=VI remember? So you halve your current for
>>a given power with 12V instead of 6, and 12V stuff is a lot easier to get
>>hold of.
>>

>
>
> So what would be a good 12v to get? I suppose I just get a smallish
> 12v SLA and wing it?
>
> Zebee


Nicads or nimh is about 70% of the weight of a SLA, I bought a Lithium
Ion battery through eBay and the weight was 64% of my NiMh battery. (3
amp hour). The charger for the Lithium battery was really cheap too. I
got it from Hong Kong, they use them in radio controlled battery powered
helicopters. It's hard to believe there is so much power packed into
something so light! I use twin 5 watt Luxeons.
 
TimC wrote:

>
> Have you come across the rectification circuit using mosfets?


Vaguely, I remember exploring this suggestion in the past, but it never
seems to lead to a circuit that I can build and use on my bicycle.

Plenty of major power ideas and circuits and I've even built 240V based
projects, but nothing usable in 6V or 12V for a bicycle.

> I haven't actually built this circuit, and worked out its limitations,
> but I don't see why it wouldn't work:


This is the problem. Theory and practice can be entirely different. I am
only talking about my experience and what I've built for my bicycle.

If someone can provide a circuit and say I've been using this whilst
commuting/touring for the last year, then I'll build it and see for myself.

As I'm not a circuit designer, only a project builder, I'll just have to
keep waiting.

Does anyone know if ***** Hunts circuits are mosfet based?
 
Humbug wrote:
> On 12/03/06 at 14:22:22 Terry Collins somehow managed to type:
>
> This isn't directed at Terry but there have been so many untruths and
> misconceptions bandied around in this thread it's a joke. You have made
> one whoopsie though...:) You do NOT need a voltage doubler to run a
> 12V globe from a normal dynamo -

I'll explain why I do in a minute# {:).


> My ancient Union dynamo produces around 60V with only the metering load
> at 20kph.


Lots of stuff produces high voltage at open circuit too.

> It produces its maximum POWER at a tad over 16V at 20kph -
> maximum current at 16V is about 520mA. With a load that limits the
> voltage to 6V it can only produce nearly 510mA.


8 Watts at 20kph you say.
First problem, I don't know of a source of 16V globes
Second problem, # I've never been able to consistently ride at 20kph.
Frankly, I can not say I know of too many people that ride like that
either. I'm an 8-10kph plodder.

However, if you are a strong rider, might be worth experimenting, if you
are still into incandescent bicycle globes.

Humbug, what was the generator you use?

I used a voltage doubler to try and pump power from my hub generator
during the day into a battery pack for lights whilst camping at night.
In the end, I decided just buying batteries was cheaper (based on prices
15 years ago {:).


> And for Tim. There are really only two practical ways to generate
> electricity on a bike. Chemically (batteries) or by swinging a magnetic
> field through a coil. That's why we still use such ancient devices as
> dynamos.


I'd really like some sources of magnesium plates for seawater power
cells, aka WWII. Basically a large we battery without acid.
>
 
On Mon, 13 Mar 2006 03:29:08 +1100, Terry Collins wrote:

> If someone can provide a circuit and say I've been using this whilst
> commuting/touring for the last year, then I'll build it and see for
> myself.


The very cheap and nasty constant current regulator on
http://hired-goons.net/lights (see LED) worked for me for quite some time.
It's not totally regulated, and does throw some energy away, but for
supply voltage not too far off required voltage it's pretty good.

I've got a slightly refined version running my current lights. 18 months+
on the two, with one blowout due to cramming too much wire in to a small
space and then having a DC plug fail and short it out.

Oh, and 2 yrs+ on the 5W version.

> Does anyone know if ***** Hunts circuits are mosfet based?


Yep, the original version was something along the lines of a 555 timer
driving the gate. Now it's a PIC so he can do smart things like adjusting
the duty cycle depending on battery condition and having multiple outputs.

--
Dave Hughes | [email protected]
Random miscellany, as opposed to that other kind of miscellany
- Patrick Shaughnessy
 
On Sun, 12 Mar 2006 14:22:22 +1100, Terry Collins
<[email protected]> wrote in aus.bicycle:

>
>> Modern LEDS give out so much light and use so little power that a
>> battery of 6 each front and rear should be doddle to power.

>
>6 x 5 Watt is still 30 watt.


That may be so but I didn't have 5 watt LEDS in mind. I have a three
LED Cateye EL200 (from memory) powered by 4 AA cells and the batteries
have been in use for months (12 km one way a day - coming home in
daylight). The light is more than sufficient to see by and be seen. I
had six of these LEDS in mind.

These high powered lights are totally unnecessay on urban roads and
even on an unlit country stretch my Cateye is more than enough to warn
me of any obstacles.


Regards
Prickles

Timendi causa est nescire
This message only uses recycled electrons
 
In aus.bicycle on Mon, 13 Mar 2006 08:29:17 +1100
Spiny Norman <[email protected]> wrote:
>
> These high powered lights are totally unnecessay on urban roads and
> even on an unlit country stretch my Cateye is more than enough to warn
> me of any obstacles.


Problem I had the other night was an unlit cycle path. They meander
in an unpredictable way, so if going any speed you need to see path
edges well ahead.

I kept reaching for the high beam switch!

Zebee
 
Random Data wrote:

> http://hired-goons.net/lights (see LED) worked for me for quite some time.

I've been watching your projects over the years for ideas. {:)

> and then having a DC plug fail and short it out.


I've given up on just about all the plugs over the years. Most rattle
and come loose, dropping lights and shorting sockets (internal jacks,
etc). You just have to laugh when you see the remains of a socket
splattered all over the inside of your project box and your battery pack
exploded for a straight short. aaaarrghhhhh.

Now I am using PP2030 (4 wire) and PP2032 (6 wire) from
http://www.jaycar.com.au. No problems over two years and a bit of bad
weather. (okay, one broken wire at an exposed junction strip {:).
 
Spiny Norman wrote:

> These high powered lights are totally unnecessay on urban roads and
> even on an unlit country stretch my Cateye is more than enough to warn
> me of any obstacles.


I am glad to hear that your eyes are still good {:) and I hope they
remain that way.

Mine are not, although they can still use a $19.99 el cheapo head led
with 3 leds to wander around a camp in total darkness, but there is no
way I'd ride my bicycle, even pottering along with out something
equivalent to a 20W light. The 50W is needed over 20kms (down hills) so
I can avoid stuff on dark roads safely.
 
On 12/03/06 at 18:25:19 TimC somehow managed to type:

> On 2006-03-12, Humbug (aka Bruce)
> was almost, but not quite, entirely unlike tea:
> > And for Tim. There are really only two practical ways to generate
> > electricity on a bike. Chemically (batteries) or by swinging a
> > magnetic field through a coil. That's why we still use such ancient
> > devices as dynamos.

>
> You misinterpreted.


Oh, OK - my brain was probably clouded by bloody work stuff.


> I was objecting to still using zener diodes for
> regulation when much better more efficient voltage
> regulation/rectification exists.


Zeners are probably about the best way of establishing a base voltage.
For bike lighting systems all they do is dissipate excess power as heat
but they ARE cheap and simple - just two of 'em back to back, a couple
of dabs with a soldering iron and the jobs done. Just think of 'em as
bulb protection rather than voltage regulation. There are loads of
better ways, ***** Hunts LVR, for example, is claimed to be VERY
efficient indeed.



--
Humbug aka VK3ZMF
BE A LOOF! (There has been a recent population explosion of lerts.)
 
On 13/03/06 at 03:39:32 Terry Collins somehow managed to type:

<snip>

> 8 Watts at 20kph you say.


I only used 20kph as the speed for testing purposes. ie. I wanted to
introduce a constant.

> First problem, I don't know of a source of 16V globes


Me either - that was ONLY at the "sweet spot" for the dynamo. I was
trying to find out what its maximum POWER output would be at 20kph by
varying the load while measuring voltage and current.

<snip>

> Humbug, what was the generator you use?


It's an ancient Union bottom bracket mounted job. Second picture down
at http://www.yellowjersey.org/dynamos.html

>
> I used a voltage doubler to try and pump power from my hub generator
> during the day into a battery pack for lights whilst camping at night.
> In the end, I decided just buying batteries was cheaper (based on
> prices 15 years ago {:).


You would've been a LOT better off using a bridge rectifier connected
between the dynamo and the battery. Even with a ****-weak Sturmey
Archer hub dynamo you can charge 12V batteries via a simple bridge
rectifier, albeit bloody slowly...:)


--
Humbug aka VK3ZMF
BE A LOOF! (There has been a recent population explosion of lerts.)
 
Humbug wrote:

OTOH, 16V meant you didn't have to worry about losses across bridge
rectifiers, etc to recharge a 12V battery pack.

> You would've been a LOT better off using a bridge rectifier connected
> between the dynamo and the battery. Even with a ****-weak Sturmey
> Archer hub dynamo you can charge 12V batteries via a simple bridge
> rectifier, albeit bloody slowly...:)


Not at my riding speed it wasn't. That was the point. I've just never
ridden faster that 15kms average, usually regarded 10km/hr average as a
good speed. Talking about a days tour.

I'd tried the full wave bridge (tag point circuit)

ah, yes, the hub was also glitzed as well. Really needed a new one, but
funds went into the bricks and motar pension fund (the home, then
infestment property,,,,,,).
 
On Mon, 13 Mar 2006 12:05:31 +1100, Terry Collins wrote:

> I've given up on just about all the plugs over the years.


I was just about to suggest PP2030 type things when I read your second
paragraph. If you're running multiple systems and want to make sure you
can't hook up the wrong one DSE do a non-compatible version, and you can
get NARVA branded ones at most auto parts shops.

If you're using 2.5mm DC plugs I've found putting a short lenght of ~5mm
PVC tube (not heat shrink) over either part provides a much more
secure join.

--
Dave Hughes | [email protected]
Careful. We don't want to learn from this. -- Calvin
 
Random Data wrote:
> On Mon, 13 Mar 2006 12:05:31 +1100, Terry Collins wrote:
>
>
>>I've given up on just about all the plugs over the years.

>
>
> I was just about to suggest PP2030 type things when I read your second
> paragraph. If you're running multiple systems and want to make sure you
> can't hook up the wrong one DSE do a non-compatible version, and you can
> get NARVA branded ones at most auto parts shops.


There are a whole range of the sort used internally in computers for
power supplies to hard disk, etc. Probably a lot cheaper that the $6 &
$8 Jaycar list the PP2030? at, but I didn't think they were waterproof
enough, i.e. I suspect you have to replace them occassionally from rust
from wet weather.

>
> If you're using 2.5mm DC plugs I've found putting a short lenght of ~5mm
> PVC tube (not heat shrink) over either part provides a much more
> secure join.


Until today, I thought they would have been too light for the currents
involved, but I found out that Canon puts 3.5A through one for a laptop.
So I might reconsider these for non-critical power. Do these ever open
circuits (lights go out)?
 
Terry Collins wrote:

>
>
> Until today, I thought they would have been too light for the currents
> involved, but I found out that Canon puts 3.5A through one for a laptop.
> So I might reconsider these for non-critical power. Do these ever open
> circuits (lights go out)?


That's the beauty of my twin luxeon setup. They run off separate current
regulators so that if one should fail for any reason I still have plenty
of light to get home with.
 
"Terry Collins" wrote:

> The caveats with hub, bracket, bottle generators are
> 1) they seem to need 15-20 km/hr to give usuable light,
> 2) you need to use myriad zener diodes to prevent bulb popping if
> zooming downhill,
> 3) they stop when you stop (some capacitor/battery combo might help
> here) and
> 4) some part has to be left on the bike (usually minimum of generator)
> all the time (theft, weather, weight, etc).


Your experience with hub and bottle dynamos may be a little out of date.
Points 1, 2 & 3 no longer apply if you get the right dynamo. Have a look
around http://www.stkildacycles.com.au/ site, especially the schmidts
dynohub, the B&M Dymotec S6 (or S12 if the finances run that high - 70%
efficiency) and the B&M Oval plus headlight, or the Oval Plus Senso.

All these are excellent lighting gear, operate at full output at 10 kmh,
voltage regulation that works, and the Oval Plus light has a capacitor that
functions as a standlight when stopped.

Point 4 is a bit academic, as dynamo lights are not really bicycle bling
gear that thieves look out for, and they need tools to remove them, unlike
those very portable battery setups.
>
> OTOH, now it would be interesting to see a system driving good leds
> compared to the old incandescent bulb jobs.


That'd be the B&M D'Topal Senso Plus on the same site. LED light that has a
100,000 hour service life, shines at 2.5 kmh and runs of a 6V dynamo Mind
you, at $125, it's beyond my lighting budget.

--
Cheers
Peter

~~~ ~ _@
~~ ~ _- \,
~~ (*)/ (*)
 
"Zebee Johnstone" wrote:

> Peter Signorini <[email protected]> wrote:
>>
>> Personally I've been yery happy with my Busch & Muller S6 dynamo. It is a
>> side-wall unit but runs with very low friction. Full output comes on at
>> 10
>> kmh or less, and it has a built-in zenner diode to regulate high speed

>
> How does it go in the wet? I've heard bottles slip?


I've not used it yet in the wet, as I don't often ride at night. My commute
is almost always daylight hours. I do use it with tyres that have a dynamo
serration around the sidewall and I'd expect this would make a big
difference. It also has a wire roller for European winter ice and snow.

> The cost of the hub did make me blink, a bottle seems a more
> reasonable proposition.
>
> I expect I'll need lights over the next few months, but can also see
> that for 3 months of the year at least I won't, and shelf life might
> annoy me then.


Yes, just discovered the impact of this on this weekend's tour. Using our
tandem for a short night ride into town from camp, pulled out the battery
light to discover it totally flat - battery switch had been moved while in
the handlebar bag. Of course I should have reversed the batteries, but the
point is I didn't and the light is dead. I can see another dynamo coming
soon for the tandem.

--
Cheers
Peter

~~~ ~ _@
~~ ~ _- \,
~~ (*)/ (*)
 
Peter Signorini wrote:

> Your experience with hub and bottle dynamos may be a little out of date.

Most probably

> you, at $125, it's beyond my lighting budget.


Isn't that all our problems?

The one time my income could afford such expenditures I was too busy
working and too busy sleeping when I wasn't working to bicycle anywhere.
Sadly, one's priorites tend to be to pay off the house and buy
investments at those time.

Nowadays, I know that my bicycle electrical needs (wants?) will only be
met by carrying a battery.
 
I have some cheap lights
to be going on with, but I want something decent.

The two are not compatible

I am very much inclining towards dynamo lighting as batteries have to
be recharged and I am sure I forgot my head once when I was running
late, so forgetting the charge is almost a given.

Go dynamo all the way, bottle or hub, that's another discussion. Why dynamo? my bike is my transport. I want to go any where at any time, i do not want to be tied by battery duration or lumbered with spares.

Can you imagine how many people would drive a car if every time you wanted to drive after dark, you had to carry a battery out to the car to run the lights.

Costly but my Schmidt and Lumotech have done over 40,000km, the odd blown bulb and lots and lots of night riding.

Tim
 
In aus.bicycle on Wed, 15 Mar 2006 16:07:16 +1100
cogcontrol <[email protected]> wrote:
>
> -Go dynamo all the way, bottle or hub, that's another discussion. Why
> dynamo? my bike is my transport. I want to go any where at any time, i
> do not want to be tied by battery duration or lumbered with spares.


Well right now I have a homebrew battery setup half made - the rest
will be done tonight once I have done this stuff work wants me to do.

1 55 watt, 1 10 watt. The 10 will be the usual one, the 55 will be
"high beam"....

A while with that and I'll have a much better idea of what I need.
And will probably go to dynamo if the battery gives me the *****.

Major hassle I can see with dynamo is not having enough light after
playing withthat...

Zebee