Battery versus Dynamo

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philg
Posts: 611
Joined: 7 May 2009, 12:13pm
Location: Porlock, Somerset

Re: Battery versus Dynamo

Post by philg »

squeaker wrote:Proper? With a rubber o-ring attachment? :roll:
Have you ever used one?

squeaker wrote:YMMV, of course!
Clearly it does
The weekend comes, my cycle hums
RJC
Posts: 188
Joined: 30 Jan 2007, 7:17pm

Re: Battery versus Dynamo

Post by RJC »

I have been using one of the Union 4268 led lights mentioned some pages back for a few months.
It was very easy to open up so I took a few snaps of the innards:
Union_im1_front.jpg
Union_im2_back.jpg

Union_im3_pcb.jpg
Union_im4_side.jpg
Union_im5_side.jpg


I also measured the DC current taken by the light when hooked up to a power supply.
If I remember correctly like the B&M Cyo it only worked with the DC polarity one way round.
4.0V 150mA
4.5V 280mA
5.0V 330mA
5.5V 335mA
6.0V 337mA

So after 5V it looks like a constant current. If I took the voltage higher possibly at some point some protection
clamps would turn on. It doesn't look like there are any inductors or transformers you would likely need
to do the same current doubling/voltage halving trick as supposedly used on the B&M Cyo etc. The voltage across
the led was 3V, so essentially this is a 1 Watt light.
I bought this light for a leave parked at station bike so cheapness and not looking expensive were a plus.
The light casts a rectangular main patch on the road about the width of one lane. I've mostly been using on roads
with street lights but on brief tests on unlit roads it had been OK. The only directly comparison I have made is
with a HL2000 1 Watt led light. The Union was much better out of the two but the Hella model would be using a
led from about 5 years ago. It would be interesting to compare it with the Axa Pico30 since they are about the same price.
The lens of the HL2000 looks identical to the Pico30.

The Union auto sensor seems to work fine, coming on when I want the lights to be on without obviously staying on when I don't.
The standlight is also good for been seen duties and parking the bike in a dark shed. Unlike the Cyo standlight it doesn't turn
off the standlight automatically, although it can be turned off with the main switch.
The weight of the light+bracket is 100gms.
Last edited by RJC on 12 Jun 2013, 3:13pm, edited 2 times in total.
RJC
Posts: 188
Joined: 30 Jan 2007, 7:17pm

Re: Battery versus Dynamo

Post by RJC »

p.s.
The underside of pcb.
Union_im6_flippcb.jpg
Brucey
Posts: 44517
Joined: 4 Jan 2012, 6:25pm

Re: Battery versus Dynamo

Post by Brucey »

Thanks for posting that. I wonder what current is going through the LED is?

I have been planning to fit one of these to an old-style dynohub for a town bike; I think from what you have posted it should work just fine.

BTW is there a UK-based source for these lights? I could only find them for sale overseas....

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
RJC
Posts: 188
Joined: 30 Jan 2007, 7:17pm

Re: Battery versus Dynamo

Post by RJC »

I would hope that most of that current is going through the LED.
I got mine from ebay Germany
http://www.ebay.de/itm/LED-Scheinwerfer-UNION-35-Lux-fur-Nabendynamo-Standlicht-Sensor-/251272922849
I did try contacting the UK agent for Marwi/Union first but he said there wasn't the demand for dynamo lights in this country.
Brucey
Posts: 44517
Joined: 4 Jan 2012, 6:25pm

Re: Battery versus Dynamo

Post by Brucey »

RJC wrote: ...I did try contacting the UK agent for Marwi/Union first but he said there wasn't the demand for dynamo lights in this country.


now, why doesn't that surprise me...?

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
james01
Posts: 2116
Joined: 6 Aug 2007, 4:48am

Re: Battery versus Dynamo

Post by james01 »

RJC wrote: It would be interesting to compare it with the Axa Pico30 since they are about the same price.
The lens of the HL2000 looks identical to the Pico30.

.


I've been using a Pico for a while, astonishing value http://www.rosebikes.co.uk/article/axa- ... aid:642367 .
edocaster
Posts: 475
Joined: 10 Apr 2013, 10:43pm

Re: Battery versus Dynamo

Post by edocaster »

james01 wrote:
RJC wrote: It would be interesting to compare it with the Axa Pico30 since they are about the same price.
The lens of the HL2000 looks identical to the Pico30.

.


I've been using a Pico for a while, astonishing value http://www.rosebikes.co.uk/article/axa- ... aid:642367 .


I'm thinking of getting a Pico. But the version I want (steady switch) is out of stock. All the other versions don't seem to have an off switch.

Is there a way of immediately switching off/discharging a capacitor standlight, so it doesn't remain lit after parking up/getting to a train station platform/etc?
jb
Posts: 1782
Joined: 6 Jan 2007, 12:17pm
Location: Clitheroe

Re: Battery versus Dynamo

Post by jb »

Whats needed is a lamp with a swiveling reflector that automaticaly elevates the beam as you speed up. I'm supprised B&M haven't come up with something like that yet.
Cheers
J Bro
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squeaker
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Joined: 12 Jan 2007, 11:43pm
Location: Sussex

Re: Battery versus Dynamo

Post by squeaker »

jb wrote:Whats needed is a lamp with a swiveling reflector that automaticaly elevates the beam as you speed up. I'm supprised B&M haven't come up with something like that yet.

I'm not, as I doubt it would meet the German regs, plus IME a decent German light works OK up to about 30mph without using a beam that dazzles on-coming traffic.
Now a switchable main / high beam for those big descents with no on-coming traffic, that would be useful ;)
"42"
MartinC
Posts: 2127
Joined: 10 May 2007, 6:31pm
Location: Bredon

Re: Battery versus Dynamo

Post by MartinC »

edocaster wrote:......................Is there a way of immediately switching off/discharging a capacitor standlight........


The B&M ones have 2 bare contacts on the rear that allow you to short out and discharge the capacitor with something conductive like a coin. Don't know anything about the Pico though, sorry.
Brucey
Posts: 44517
Joined: 4 Jan 2012, 6:25pm

Re: Battery versus Dynamo

Post by Brucey »

edocaster wrote: Is there a way of immediately switching off/discharging a capacitor standlight, so it doesn't remain lit after parking up/getting to a train station platform/etc?



if you fit an additional switch to the unit (e.g. to the LED or the capacitor) then the light could be switched off, but you would have to remember to turn it back on again later. Electrenics engineers with whom I have worked have sworn blind that mechanical switches are the least reliable parts BTW. Its not been my experience, but hey...

cheers
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~~~~~~~~~~~~~~~~~~~~~~Brucey~~~~~~~~~~~~~~~~~~~~~~~~
jb
Posts: 1782
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Location: Clitheroe

Re: Battery versus Dynamo

Post by jb »

squeaker wrote:
jb wrote:Whats needed is a lamp with a swiveling reflector that automaticaly elevates the beam as you speed up. I'm supprised B&M haven't come up with something like that yet.

I'm not, as I doubt it would meet the German regs, plus IME a decent German light works OK up to about 30mph without using a beam that dazzles on-coming traffic.
Now a switchable main / high beam for those big descents with no on-coming traffic, that would be useful ;)

It would only need to be a tiny amount. When I set my cyo up for normal riding I find that when decending quickly I could just do with it slightly higher to penetrate the unknown.
Cheers
J Bro
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[XAP]Bob
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Joined: 26 Sep 2008, 4:12pm

Re: Battery versus Dynamo

Post by [XAP]Bob »

I'm considering adding a small 12V system to my trike.
A small LiPo battery (RC style) would happily drive some after market car lights. Put them on a post extending the offside seat tube.
Would also look at mounting my forward facing camera there - capture what I'm doing as well as a far forward view (which is what I currently have).

It's not too expensive, and would make an interesting addition to my lighting and electronics. I have seen a few 12V/USB power packs - and that is attractive to me - although I might just get a separate USB PSU from the 12V (or just rely on my Dynamo 5V supply).

Basically the lights would be "fixed" and the battery would be in my pannier/side pods or a custom pocket.
Just need to work out the pole ;)

If I can use it as a push handle then all the better ;)
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.
edocaster
Posts: 475
Joined: 10 Apr 2013, 10:43pm

Re: Battery versus Dynamo

Post by edocaster »

RJC wrote:It would be interesting to compare it with the Axa Pico30 since they are about the same price.
The lens of the HL2000 looks identical to the Pico30.


I think this - https://plus.google.com/u/0/photos/1128 ... 7953872609 - referred to from this German forum - http://www.radreise-forum.de/topics/976402#Post976402 - shows just that. I believe the third picture is the Pico, and the fifth the Union (fourth appears to be both combined).
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