dynamo lighting

Terry Collins said:

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 hidden]
"Two of my imaginary friends reproduced once ... with negative results."
- Ben, ASR

Zebee Johnstone said:

In aus.bicycle on Sat, 11 Mar 2006 13:44:18 +1100

Random Data said:

Zebee Johnstone said:

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 said:

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.

Quoted message said:

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 [censored] Hunts circuits are mosfet based?

Humbug said:

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# {:-).

Quoted message said:

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

Lots of stuff produces high voltage at open circuit too.

Quoted message said:

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 {:-).

Quoted message said:

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.

Quoted message said:

Terry Collins said:

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.

Quoted message said:

Does anyone know if [censored] 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 hidden]
Random miscellany, as opposed to that other kind of miscellany
- Patrick Shaughnessy

On Sun, 12 Mar 2006 14:22:22 +1100, Terry Collins
<[email hidden]> wrote in aus.bicycle:

Quoted message said:

Quoted message said:

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 said:

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 said:

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. {:-)

Quoted message said:

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 said:

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:

Quoted message said:

On 2006-03-12, Humbug (aka Bruce)
was almost, but not quite, entirely unlike tea:

Quoted message said:

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.

Quoted message said:

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, [censored] 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>

Quoted message said:

8 Watts at 20kph you say.

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

Quoted message said:

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>

Quoted message said:

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

Quoted message said:

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 [censored]-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.

Quoted message said:

You would've been a LOT better off using a bridge rectifier connected
between the dynamo and the battery. Even with a [censored]-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,,,,,,).

Terry Collins said:

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 hidden]
Careful. We don't want to learn from this. -- Calvin

Random Data said:

Terry Collins said:

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.

Quoted message said:

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 said:

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 said:

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.

Quoted message said:

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 said:

Peter Signorini said:

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.

Quoted message said:

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 said:

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

Most probably

Quoted message said:

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 said:

-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 [censored].

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

Zebee