Son 28 powering B&M iQ-X and VeloCharger USB

[FaustoCoppi]

We’ve just returned from a short 21 mile shakedown ride to test out the new son28 dynohub. It’s wired  to a VeloCharger USB and a B&M lumotec iQ-x. Both sets of cables are soldered and shrink wrapped into one set of connectors. On today’s run I had the lamp on and a power bank connected. The light operated perfectly, however the power bank didn’t take on any charge.
Is it a case of choosing light or charger? We were averaging 12.3 mph.

[Danneaux]

...shakedown ride to test out the new son28 dynohub...

Is your dynohub the SON Deluxe? If so, it is very much "either or" for lighting or charging.

If it is a standard SON, then 12.3mph is right at the baseline where most chargers achieve full power. The VeloCharger site says..."Charging will start at approximately 8mph (12.5km/h)". That's where power generation starts, but may not be full power.  Some power banks have a base charging threshold which you might not have achieved at that speed.

Have you tried going a little faster to see if it makes a difference?


Best,

Dan.

[PH]

Is it a case of choosing light or charger?

I'm sure someone will be able to give you a technical answer, but the non tech one is - Yes, one or the other.
I think, from memory, the velocharger starts charging from 7mph and the light reaches full brightness at at around the same, so together and without losses you're up to 14mph before it starts charging.  There are more efficient chargers, which are unsurprisingly more expensive, but even the best won't power a light and offer much charge unless used by fast riders.
EDIT - Dan was in here first, apologies for any duplication...

[FaustoCoppi]

Dan, thank you, we were riding at our usual speed, so sadly not much chance of upping the power! The hub is a standard son28, I established at time of order that I needed to run two devices. The charge bank may be the issue then it’s a LAX pro 12,000 mah, which has only ever been charged from the 240 v mains via a iPhone charging triangle and lead. I’ve been looking at the SKS ComPit + system as the power bank is more bike specific perhaps that would take a charge at our touring speed of 12 mph which once we are fully loaded never increases.

[Danneaux]

The charge bank may be the issue...

That's where I would start. If you have access to or can purchase an inexpensive inline USB meter, you can tell how much your charging system is producing in both volts and current, and can also determine how much your power bank is drawing/demanding. I paid something like USD$4 for mine from a vendor on eBay and it has worked well.

...our touring speed of 12 mph which once we are fully loaded never increases.

<nods> Actually, that's not a bad pace when touring fully loaded. I remember reading any number of "touring books" in the late-1970s/early-1980s that indicated a 10mph average overall was considered "standard", so you're about 20% above that. 

Best,

Dan.

[mickeg]

Some lights will draw all power out of the hub and dump excess power to heat.  I think they do that to make sure that the tailight that usually does not have overvoltage protection does not blow out.  I can't say if your headlight is one of such lights, but it might be.  If you had a multimeter and could monitor your AC voltage out of the hub with the light on, that would tell you if the voltage can rise very high or not. 

Generally I assume that the hub will supply a lighting system or a USB charger, not both.  I have found that if I have my B&M IQ XS and a Secula taillight on, that my Sinewave charger will only produce about one fourth as much power as when my lights are off.  I was pleasantly surprised that I got any power at all out of the Sinewave in this scenario.

[PH]

You might find this interesting
https://www.cyclingabout.com/best-dynamo-usb-chargers-bicycle-touring-bikepacking/

[FaustoCoppi]

PH thank you, I have already stumbled across this link, not being terribly technical it hasn’t helped me! Next time out I’ll turn the light off and see if this sends all the generated power to my chosen power bank, its slightly annoying and disappointing that the set up appears to be an ‘either or’ arrangement, rather than running a light and charging the power bank simultaneously.

[PH]

PH thank you, I have already stumbled across this link, not being terribly technical it hasn’t helped me! Next time out I’ll turn the light off and see if this sends all the generated power to my chosen power bank, its slightly annoying and disappointing that the set up appears to be an ‘either or’ arrangement, rather than running a light and charging the power bank simultaneously.

I'm not the most technical either, what I got from that was how unlikely it would be to power both light and charger at the same time at touring speeds.  Though unless you're hoping to run a daytime light there probably isn't much need to. Maybe it's similar to running two lights, something I did before LED's, it was frustrating turning the 2nd on and off, below a certain speed (12mph?) there'd be more light from the single than the pair. 
I might be able to borrow a USB meter, though maybe not till after lockdown.  I wouldn't mind having a play with my own set up, rather than guessing and getting it wrong when I need it.

[John Saxby]

the set up appears to be an ‘either or’ arrangement, rather than running a light and charging the power bank simultaneously

Yep, I learned this in 2014/15 when I was trying to run an AXA headlight and an Anker powerbank off my SON 28-mit-Sinewave charger.  Happily, I was touring in northern Europe st the time, so was able to recharge my power bank every other day, hence the various parasitic devices feeding off that.

I resolved the problem by ditching the AXA headlight in 2015--helped by the fact that its mounting bracket fractured, but the switch was wonky in any case.  Since then, my SON 28/Sinewave setup charges only my Anker battery, and does so very quickly: from aboyut 15-20% to full in 3 - 4 hours.

My headlight is an old-but-still-sound Cygolite, which I use almost exclusively on the flashing mode so as to be seen in daytime. Used this way, it can go 3 days or more without a charge. I use it only very occasionally at night.

[energyman]

The amount of power that can be generated on the majority of hubs is 3 Watts according to the published specs.
It's not a lot but with LED lighting it's fine.
Connect something else which also draws power and the hub can't cope.
In the days of halogen lights being the bees knees I once saw a rear wheel with TWO "rim dynamos" feeding the front light !
Cateye had a range of halogen lights running off a lead acid battery but they only lasted 40 minutes just enough to get me from night school to home in winter !
Thankfully we now have Li-on batteries and LED lights which weigh a lot less.
(Yes I do appreciate they were called dynamos but were alternators.)

[PH]

The amount of power that can be generated on the majority of hubs is 3 Watts according to the published specs.

Here's what SON say

How much voltage and wattage does a SON hub dynamo supply?
Nominal values are 6 volts and 3 watts. They are achieved at moderate speeds depending on wheel size and generator type. The real values depend on the electrical load to a large extent indeed. Running with no electrical load results in remarkably higher voItage. At high speeds and with suitable electrical load you may use significantly more power.

But then sadly for FaustoCoppi later on the same FAQ page it says

Can you charge a device with lights switched on at the same time?
Most charging devices do not charge if the headlight shines at the same time; some of them might work with a small fraction of their nominal power. It makes sense to switch the light off when powering a USB-charger. You may connect an Edelux II DC 6-75V and a navigation device to the 12 V output on a „Forumslader V5“. If the buffer battery of the Forumslader V5 is well-charged you can power the light and your device at the same time.

https://nabendynamo.de/en/service/faqs/

I know it's possible to run two 3W halogen bulbs, not only have I done so, SON used to supply paired lights to simplify it.  The question is at what speed does it become possible and practical, in the case of a light and charger, I suspect it's a good bit faster than touring speeds, and for those going that much faster they'd probably resent the drag.

[martinf]

When I got my Thorn Raven Tour in 2012 I specified the older type of SON hub rather than the latest model for two reasons:

- it has a steel axle (I think the newer one has an aluminium alloy axle)
- the electrical output was slightly higher, which might be useful if I ever have devices that need charging.

With LED lamps the electrical output doesn't seem to matter much. I run two rear lamps off the hub generator on this bike and several others, but this works well even with a lower output hub. A rear lamp doesn't take much power.

So far I don't have a bike GPS or smartphone. On my 2011 tour I charged my old phone before leaving and it lasted for a month with frugal use. I didn't even use the spare battery I packed.

[steve216c]

So far I don't have a bike GPS or smartphone. On my 2011 tour I charged my old phone before leaving and it lasted for a month with frugal use. I didn't even use the spare battery I packed.

Nokia 3310 and I went to USA for 3 weeks back in the day. I forgot to turn off on flight, and probably talked on phone for no more than 30 minutes total in those 3 weeks, and got home still on 1 bar of juice.

My iPhone struggles to make it through till bedtime each day.

As a phone, the 3310 wins every day of the week. A practical design classic with no need for chargers on a long ride.

[UKTony]

So far I don't have a bike GPS or smartphone. On my 2011 tour I charged my old phone before leaving and it lasted for a month with frugal use. I didn't even use the spare battery I packed.

Bought my first smart phone recently but have kept the Old Skool Nokia for reasons already stated here also because of size and weight - 100g as opposed to 275g (inc case) for the smartphone, the Nokia is not unwieldy carried in a trouser or jacket pocket but the smartphone has to go in the pannier or saddlebag.   Also the Nokia battery, bought cheaply on eBay, is still fine after about 8 years and I find I can get a signal on the Nokia in places where smartphones have a problem (I’m told this is because the old phones work on 2G). So whilst the smartphone is brilliant in many ways I don’t think I shall be dispensing with the Nokia for bike rides or walks in remoter places, any time soon.