Dynamo lights - "hub only"

Can somebody confirm that front dynamo headlights which are sold as "hub
only" can in fact be used with a bottle and that the only difference
between hub only and other dynamo headlights is a switch rather than
anything [else] electrical? (I understand that with a couple Busch and
Muller models this isn't true due to the switch being wired on the earth
rather than the live, but generally .....). Or am I plain wrong?

Thanks

Keiron wrote:
Can somebody confirm that front dynamo headlights which are sold as "hub
only" can in fact be used with a bottle and that the only difference
between hub only and other dynamo headlights is a switch rather than
anything [else] electrical? (I understand that with a couple Busch and
Muller models this isn't true due to the switch being wired on the earth
rather than the live, but generally .....). Or am I plain wrong?

Thanks

Should be fine, it is probaly an imprecise way of preventing the use with DC

--
/Marten

info(apestaartje)m-gineering(punt)nl

On Aug 7, 6:10*pm, Keiron wrote:
Can somebody confirm that front dynamo headlights which are sold as "hub
only" can in fact be used with a bottle and that the only difference
between hub only and other dynamo headlights is a switch rather than
anything [else] electrical? (I understand that with a couple Busch and
Muller models this isn't true due to the switch being wired on the earth
rather than the live, but generally .....). Or am I plain wrong?

Thanks

You'll be okay. But you should consider what kind of light it is that
you want to run. The expected service life of a halogen bulb is around
100 hours; it pays to switch it off when running on a hub dynamo. You
leave that running all the time, better to have a handful of
replacement globes in your toolbox. With a LED it doesn't matter; the
service life is effectively infinite. All my lights, four per bike,
are LEDs, so I leave them running as daylight running lamps. -- Andre
Jute

On 07/08/10 10:10 AM, Keiron wrote:
Can somebody confirm that front dynamo headlights which are sold as "hub
only" can in fact be used with a bottle and that the only difference
between hub only and other dynamo headlights is a switch rather than
anything [else] electrical? (I understand that with a couple Busch and
Muller models this isn't true due to the switch being wired on the earth
rather than the live, but generally .....). Or am I plain wrong?

Thanks

While both bottle and hub dynamos are nominally 6V/3W/0.5A, in fact the
hub dynamos are able to deliver significantly greater wattage than a
bottle dynamo. It's possible that some dynamo headlights require the
higher power.

Other than that, it's hard to imagine a reason why a headlight would be
"hub only" though not hard to imagine why a headlight could be "bottle
only."

On 09/08/2010 17:12, SMS wrote:
On 07/08/10 10:10 AM, Keiron wrote:
Can somebody confirm that front dynamo headlights which are sold as "hub
only" can in fact be used with a bottle and that the only difference
between hub only and other dynamo headlights is a switch rather than
anything [else] electrical? (I understand that with a couple Busch and
Muller models this isn't true due to the switch being wired on the earth
rather than the live, but generally .....). Or am I plain wrong?

Thanks

While both bottle and hub dynamos are nominally 6V/3W/0.5A, in fact the
hub dynamos are able to deliver significantly greater wattage than a
bottle dynamo.

Is that actually true? You can overvolt a bottle in the same way as a
hub, though obviously you get greater wear + propensity for slip.

It's possible that some dynamo headlights require the
higher power.

None do.

Other than that, it's hard to imagine a reason why a headlight would be
"hub only" though not hard to imagine why a headlight could be "bottle
only."

It's the switch. Bottle lamps don't have one.

On 09/08/10 9:15 AM, Clive George wrote:
On 09/08/2010 17:12, SMS wrote:
On 07/08/10 10:10 AM, Keiron wrote:
Can somebody confirm that front dynamo headlights which are sold as "hub
only" can in fact be used with a bottle and that the only difference
between hub only and other dynamo headlights is a switch rather than
anything [else] electrical? (I understand that with a couple Busch and
Muller models this isn't true due to the switch being wired on the earth
rather than the live, but generally .....). Or am I plain wrong?

Thanks

While both bottle and hub dynamos are nominally 6V/3W/0.5A, in fact the
hub dynamos are able to deliver significantly greater wattage than a
bottle dynamo.

Is that actually true? You can overvolt a bottle in the same way as a
hub, though obviously you get greater wear + propensity for slip.

It's possible that some dynamo headlights require the
higher power.

None do.

Other than that, it's hard to imagine a reason why a headlight would be
"hub only" though not hard to imagine why a headlight could be "bottle
only."

It's the switch. Bottle lamps don't have one.

Right, but a "hub-only" headlight with a switch could certainly be used
on a bottle dynamo. There must be some other reason that they would have
said "hub-only." Maybe there's a standlight battery that is charged by
the hub dynamo and it would require that the bottle dynamo be always
engaged to achieve the same functionality. Maybe it's an electronic
switch rather than a mechanical switch that would require the bottle
dynamo to be engaged prior to turning on the light. Maybe it won't work
with the bicycle frame as the return path for whatever reason.

On 09/08/2010 17:35, SMS wrote:
On 09/08/10 9:15 AM, Clive George wrote:
On 09/08/2010 17:12, SMS wrote:
On 07/08/10 10:10 AM, Keiron wrote:
Can somebody confirm that front dynamo headlights which are sold as
"hub
only" can in fact be used with a bottle and that the only difference
between hub only and other dynamo headlights is a switch rather than
anything [else] electrical? (I understand that with a couple Busch and
Muller models this isn't true due to the switch being wired on the
earth
rather than the live, but generally .....). Or am I plain wrong?

Thanks

While both bottle and hub dynamos are nominally 6V/3W/0.5A, in fact the
hub dynamos are able to deliver significantly greater wattage than a
bottle dynamo.

Is that actually true? You can overvolt a bottle in the same way as a
hub, though obviously you get greater wear + propensity for slip.

It's possible that some dynamo headlights require the
higher power.

None do.

Other than that, it's hard to imagine a reason why a headlight would be
"hub only" though not hard to imagine why a headlight could be "bottle
only."

It's the switch. Bottle lamps don't have one.

Right, but a "hub-only" headlight with a switch could certainly be used
on a bottle dynamo.

Indeed.

There must be some other reason that they would have
said "hub-only."

Nah.

Maybe there's a standlight battery that is charged by
the hub dynamo and it would require that the bottle dynamo be always
engaged to achieve the same functionality. Maybe it's an electronic
switch rather than a mechanical switch that would require the bottle
dynamo to be engaged prior to turning on the light.

Don't think so. Choose the simplest answer : the manufacturers have said
"For hub dynamo" and somebody's overzealously interpreted it. If it was
on eg Peter White's site, I'd believe it, but I'd expect an explanation
there.

Maybe it won't work
with the bicycle frame as the return path for whatever reason.

Worth looking at, and wiring as a 2-wire system for that. But that just
needs a bit of care.

Op 9-8-2010 18:15, Clive George schreef:

It's the switch. Bottle lamps don't have one.

Yes the have.

Lou