Front light bulbs - LED vs. halogen vs. krypton vs. xenon...

[Tosspot]

Josey wrote:
> "Jim D" <[email protected]> wrote in message
>
> Take a look at Busch and Muller Ixon. Not cheap, but very good for LED
> portable solution. Runtime fis with your need, and It's OK on it's own on
> the unlit section of my route.
>
> Just over £50 imported from Germany (several sellers on Ebay) Including
> batteries and charger. This is also good because it charges the batteries
> inside the lamp, without removal.

Streuth, thats 50 euros over here. I'm in the wrong business, I should
be shipping those things back.

 

[Andrew Price]

On 1 Nov 2006 04:49:44 -0800, "Alex" <[email protected]> wrote:

>Hmm, not quite inexpensive at 40 quid, but the Cateye EL530 is getting
>some very good words.

Any idea how it compares to the B&M Ixon?

 

[Pete Biggs]

> 5W minimum for halogen, is my suggestion.

When I wrote the above I was thinking more about MR11-based systems and
forgetting about the large 3W halogen light I used to use with a dynamo.
That was quite useful on unlit roads. So it depends on the type and size
of the lamp and bulb as well as the wattage (and the amount of
over-volting).

~PB

 

[Josey]

"Tosspot" <[email protected]> wrote in message

> Streuth, thats 50 euros over here. I'm in the wrong business, I should be
> shipping those things back

Which is why I bought one from Germany, but add the batteries and charger
and shipping gets you to about £50.

Buy one from a UK dealer and the battery/charger model is £75 + shipping.

Jc.

 

[Zog The Undeniable]

Jim D wrote:

> I'm trying to determine the relative suitability of LED, Xenon,
> halogen and krypton bulbs for use in cycle headlights for use on unlit
> roads. I hear people say that LEDs are the most efficient, but I also
> hear people say that it's difficult to focus them into a long enough
> beam for use on dark roads. I hear people say that Halogen lamps are
> more suitable because they give longer beams, but are not as
> efficient. I hear people say that krypton bulbs are better, and I hear
> people say that xenon bulbs are better still. Anyone agree?
>
> What I want, personally, is a front light that is *inexpensive* and
> will give a long and sufficiently wide, bright beam for 2-3 hours on 2
> or 4 rechargeable NimH 'AA' batteries - and isn't likely to blow its
> bulbs. Is that feasable? Which of the above bulb types is most likely
> to be in such a lamp?

LEDs are not good when run on rechargeable batteries. They are very
voltage-dependent. I have done the measuring with a light meter and the
output on NiMH is roughly halved compared with fresh alkaline cells. If
you use LEDs, I strongly recommend lithium AA cells, as they are a full
1.5V with a much flatter discharge curve (and, as a bonus, are spookily
lightweight).

As you want to use rechargeables, a reasonable 4 x AA halogen lamp will
fit the bill. Cateye make a Micro-Halogen one and, if you can find it,
the Energizer halogen lamp is pretty good too; sometimes it comes as a
set with a halogen *rear* lamp of identical design and power, which is
probably overkill. They both use 2.4W 4.8V bulbs. You get just over
two hours' run time on mere 1300mAh cells, so the modern 2100mAH or
2500mAh cells will give you up to 4 hours, and just enough light to see
by. The bulbs last a very long time in my experince - in fact, I've
never actually had one fail although they get a bit dimmer over a long time.

Krypton bulbs are just a little brighter than standard torch bulbs, and
not worth considering. Xenon is a much-misused term, either meaning
halogen bulbs with a bit of xenon gas in them so the filament can be
burnt harder, or a full HID arc system, but you won't find xenon in any
lamp intended for 4 x AA power.

 

[Anthony Jones]

Zog The Undeniable wrote:
> LEDs are not good when run on rechargeable batteries. They are very
> voltage-dependent.

That's an overgeneralisation. Regulated LEDs lights are available, which are
entirely voltage-independent over the normal operating range of
alkaline/NiMH batteries.

Anthony

 

[Anthony Jones]

Andrew Price wrote:
>>Hmm, not quite inexpensive at 40 quid, but the Cateye EL530 is getting
>>some very good words.
>
> Any idea how it compares to the B&M Ixon?

I haven't seen a EL-530, but I'd /guess/ that like most Cateye lights it's
unregulated (meaning the light output quickly decreases as the batteries
run out), and that it probably doesn't have quite as good a beam pattern on
the road.

Anthony

 

[Josey]

"Zog The Undeniable" <[email protected]> wrote in message

> LEDs are not good when run on rechargeable batteries. They are very
> voltage-dependent. I have done the measuring with a light meter and the
> output on NiMH is roughly halved compared with fresh alkaline cells. If
> you use LEDs, I strongly recommend lithium AA cells, as they are a full
> 1.5V with a much flatter discharge curve (and, as a bonus, are spookily
> lightweight).

You need to use a constant current/regulated supply.

Jc.

 

[Pete Biggs]

Zog The Undeniable wrote:

> LEDs are not good when run on rechargeable batteries.

Here we go again.

I use LED lights with rechargeables, and in contrast to when I used
alkalines, they're always nice and bright now.

> They are very voltage-dependent.

Which is why they're better with NiMH or NiCad batteries than Alkalines --
unless you fit new batteries every half hour.

> I have done the measuring with a light meter and
> the output on NiMH is roughly halved compared with fresh alkaline
> cells.

There's not that much difference in initial brightness with the Smart and
Eurolight LEDs I use, and alkaline cells in them don't stay above 1.2V for
long anyway. The /average/ brightness is higher with rechargeables when
charged frequently.

Modern LED lights are so bright that it doesn't really matter about not
having the most out of them anyway -- which I think you could only have with
lithiums.....

> If you use LEDs, I strongly recommend lithium AA cells, as
> they are a full 1.5V with a much flatter discharge curve (and, as a bonus,
> are
> spookily lightweight).

They are much more expensive than using rechargeables and you need to carry
spares once uncertain how much juice is left, negating the weight saving.
More expensive than bulk-bought alkalines as well in terms of cost per hour.

~PB

 

[Clive George]

"Pete Biggs" <[email protected]> wrote in
message news:[email protected]...
>> 5W minimum for halogen, is my suggestion.
>
> When I wrote the above I was thinking more about MR11-based systems and
> forgetting about the large 3W halogen light I used to use with a dynamo.
> That was quite useful on unlit roads. So it depends on the type and size
> of the lamp and bulb as well as the wattage (and the amount of
> over-volting).

Yes - proper bike lights have a better beam pattern. I use 3w halogen on
unlit roads.

cheers,
clive

 

[Stephen]

Anthony Jones wrote:
> I haven't seen a EL-530, but I'd /guess/ that like most Cateye lights it's
> unregulated (meaning the light output quickly decreases as the batteries
> run out), and that it probably doesn't have quite as good a beam pattern on
> the road.
>
> Anthony

I have an EL500 and I pretty sure it is regulated. I have no reason to
think that the EL530 wouldn't be as well.

 

[Anthony Jones]

Stephen wrote:
> I have an EL500 and I pretty sure it is regulated.

What makes you think that?

See appendix 4 (right at the bottom) here:

http://www.meiring.org.uk/pdm/Audax/SolidLights_Review.shtml

There are German versions of the Cateye lights (e.g. EL500 vs EL500G),
which *are* regulated, but I've never noticed them for sale over here.

Anthony

 

[Stephen]

Anthony Jones wrote:
> Stephen wrote:
> > I have an EL500 and I pretty sure it is regulated.
>
> What makes you think that?
>
>
This picture of the inside of my EL500...
http://i68.photobucket.com/albums/i26/srmoll/OddsnSods/EL500Inside.jpg

 

[Anthony Jones]

Stephen wrote:
> This picture of the inside of my EL500...
> http://i68.photobucket.com/albums/i26/srmoll/OddsnSods/EL500Inside.jpg

IIRC, the EL500 has a switch that electronically 'latches', i.e. contact of
the switch toggles the light on or off (correct me if I'm wrong on that). I
suspect that is what the circuit is for. I cannot see a transistor large
enough for the circuit to be a linear regulator, nor an inductor as I would
expect to see in a switching regulator.

Anthony

 

[Stephen]

Anthony Jones wrote:
> Stephen wrote:
> > This picture of the inside of my EL500...
> > http://i68.photobucket.com/albums/i26/srmoll/OddsnSods/EL500Inside.jpg
>
> IIRC, the EL500 has a switch that electronically 'latches', i.e. contact of
> the switch toggles the light on or off (correct me if I'm wrong on that). I
> suspect that is what the circuit is for. I cannot see a transistor large
> enough for the circuit to be a linear regulator, nor an inductor as I would
> expect to see in a switching regulator.
>
> Anthony

The black blob with U1 next to it is a 16 pin integrated circuit of
some kind.
The device labelled Q1 is a transistor, and some surface mount
transistors like that, are easily capable of switching 0.25A, in fact
Philips do a SOT-23 transistor capable of handling 2A. So it is quite
reasonable to expect that somewhere in there is a power regulator.
Otherwise it seems an awful lot of circuit for a magnetic switch.

 

[Anthony Jones]

Stephen wrote:
> The black blob with U1 next to it is a 16 pin integrated circuit of
> some kind.
> The device labelled Q1 is a transistor, and some surface mount
> transistors like that, are easily capable of switching 0.25A, in fact
> Philips do a SOT-23 transistor capable of handling 2A.

I'm not an electrical engineer by any means, so I may be getting out of my
depth here, but assuming a linear regulator surely power dissipation is
going to be the issue, not current? I don't think a switching regulator
without an inductor would work (since fully charged NiMH batteries would
provide more than the maximum rated current through the LED). Perhaps
Cateye uses the same IC in different configurations for various lights
(flashing etc.), explaining the complexity?

Anyway, none of this explains the current readings that I linked to
previously, nor the existence of the EL500G. If you're willing to take some
current vs. voltage readings, I could be convinced (although then I'd be
tempted to think that you have a EL500G rather than an EL500).

Anthony

 

[Ian Smith]

On Thu, 02 Nov 2006, Anthony Jones <[email protected]> wrote:
>
> I'm not an electrical engineer by any means, so I may be getting out of my
> depth here, but assuming a linear regulator surely power dissipation is
> going to be the issue, not current? I don't think a switching regulator
> without an inductor would work (since fully charged NiMH batteries would
> provide more than the maximum rated current through the LED). Perhaps
> Cateye uses the same IC in different configurations for various lights
> (flashing etc.), explaining the complexity?

You can regulate LEDs with PWM and don't need an inductor. At least
one of teh bike light manufacturers appears to do so, as the link you
(I think) previously provided explains.

regards, Ian SMith
--
|\ /| no .sig
|o o|
|/ \|

 

[Stephen]

Anthony Jones wrote:
> Perhaps
> Cateye uses the same IC in different configurations for various lights
> (flashing etc.), explaining the complexity?
>
> Anyway, none of this explains the current readings that I linked to
> previously, nor the existence of the EL500G. If you're willing to take some
> current vs. voltage readings, I could be convinced (although then I'd be
> tempted to think that you have a EL500G rather than an EL500).
>
> Anthony

The EL500 is either on or off, there is no flashing or anything like
that. If I have time in the next few days I'll do the measurements.

 

[Anthony Jones]

Ian Smith wrote:
> You can regulate LEDs with PWM and don't need an inductor. At least
> one of teh bike light manufacturers appears to do so, as the link you
> (I think) previously provided explains.

Indeed, I hadn't noticed that. The light in question /is/ described as being
an 'unusual regulator design' though.

Anyway, hopefully Stephen will be able to take some measurements. I'll be
happy to be prooven wrong if it makes my future light purchases easier!

Anthony

 

[=?ISO-8859-1?Q?G=FCnther?= Schwarz]

Anthony Jones wrote:

> [Cateye HL-EL500G]
> Anyway, hopefully Stephen will be able to take some measurements. I'll
> be happy to be prooven wrong if it makes my future light purchases
> easier!

Andreas Oehler published the following figures on the bikecurrent
mailing list:

##################################################################
Date: Tue, 19 Oct 2004 22:39:58 +0200
To: [email protected]
Subject: Re: [BC] CatEye HL-EL500G: regulated?

I haven't found a way to get to the PCB(s) without damaging the lamp
permanently - so I just had the possibility to do some measurements at
the battery contacts. The "meter" I have here in the moment is less
accurate than what I am used to - so don't over-interpret the numbers:

Cateye EL-500G

voltage | current | low batt indicator
---------+-----------+--------------------
4.00 V | 440 mA | on (light darker)
4.25 V | 520 mA | on
4.60 V | 500 mA | on
4.80 V | 460 mA | off
6.00 V | 400 mA | off
6.50 V | 360 mA | off

This means, the lamp is regulated: It consumes a constant 2.2-2.4 Watt
when battery voltage is higher than 4.25 Volt. It can be used either
with alkaline or NiMH cells.

##################################################################

As far as I can tell the regulating circuit is inside the light head. As
this part is ultrasonic welded like Andreas I did not manage to open
it.
The figures show that the light works well with rechargables. It does
not make the best use of them as light output drops when the cells
reach 1.0 V each. IME it works for about 4 h under real world
conditions (well used cells, temperatures typical for night time
rides). Also the low battery warning lights up quite early.
Cateye claims 6 h for the G-version. I never reached this but it is well
less exegarated than their run time claims for the international
version or the infamous 100 h for the HL-EL300.

Günther