Busch+Müller USB-Werk
 

In the spring of 2017 I purchased a Bush+Müller USB-Werk, as part of an update I was doing to a Rivendell Atlantis, which I had recently purchased, and which had been equipped with a SON-28 hub and two Haolgen lights. I also purchased a B+M IQ-X light — this was just before Peter White announced (in April 2017) that the USB-Werk and the IQ-X were incompatible.

Since then I've used the USB-Werk fairly successfully on two bikes — mostly my Rando bike, but also my commuter bike. I have female 3.5mm x 1.35mm plugs on both bikes, and simply put the USB-Werk into my handlebar bag. I had some problems with the output being intermittent, but put that down to defective wiring on the bike, or in the device. (I had a Magellan Cyclo GPS that eventually refused to charge at all, even when plugged into its wall wart.)

However, recently the "intermittence" seemed to have happened more often. On a recent three-day tour, I could not get any power out of the USB-Werk at all, and was forced to rely on a 10 Wh battery, which barely made it through the three days. What's frustrating about this is that when I run a test with a voltmeter in my shop, everything works fine; it fails only when I'm on the road.

In at attempt to diagnose which connector is defective, I bought a couple of $4 digital voltmeters and a bridge rectifier circuit, and cracked the case of the USB-Werk so that I could solder them directly onto the circuit board inside, eliminating the connectors from the system.

https://cimg4.ibsrv.net/gimg/bikefor...ace6f00af.jpeg
USB-Werk, with voltmeter showing the 5V output (from the Cache battery). There is a second voltmeter on the other side of the wooden stick that shows the input voltage. Because the input is AC, and the voltmeter reads DC, this reading is actually the output of the bridge rectifier circuit that you can see under the elastic band on the left-hand-side of the USB-Werk.

This arrangement, zip-tied to my handlebars, let me monitor the input and output voltages not only in the shop, but also while riding. What I found is that in the shop, with the bike in a workstand, I could spin the wheel and see the input voltage rise to about 6V. Once the Cache battery had time to charge, the output would rise to 5V and stay there. When I took the bike for a ride, I would initially see the same 5V output, but after about 15 minutes of riding, the output would become intermittent. (These voltmeters don't register below about 2V, so I don't know if the output voltage drops to 0, or just to below what the voltmeter can register, but either way, it's useless for charging a device.) After another 5 or 10 minutes, there is no more "intermittence": there is consistently no detectable output.

I had hoped that by cracking the case, I might see an obvious loose connection, or some other evidence of a failing component. I did not, but I'm going to post photos here of the internals, in case some more-knowledgeable BF member can learn from them. The two cache batteries are 150mAh LiFe cells.


https://cimg6.ibsrv.net/gimg/bikefor...a23159b43.jpeg
USB-Werk circuit board and batteries

https://cimg1.ibsrv.net/gimg/bikefor...da56ba213.jpeg
USB-Werk circuit board (front)

https://cimg2.ibsrv.net/gimg/bikefor...4372fdda2.jpeg
USB-Werk circuit board (back)

https://cimg5.ibsrv.net/gimg/bikefor...944d1485f.jpeg
LiFe batteries

I have a Luxos U which I believe uses similar circuitry. This website (a google translation) indicates that the Luxos U uses the same battery pack as the Werk:
https://translate.google.com/transla...00271,15700301

On my Luxos U there is a little red light on the remote switch that indicates if there is adequate charge in the pass through cache battery to charge a device through the USB port.

I have often noticed that the red light goes off and on when charging things, and I have come to the conclusion that when I am draining the cache battery (drawing more power out of the cache battery than replenishment rate), that eventually the red light goes out and the charge stops for a while and then it starts charging again later. I do not know if this is true or not, but that is the general assumption I have made.

If I am right, maybe a new battery pack would solve your problem? It is my understanding that Peter White sells them, but I do not know the price.

But, you said you got no power out of it during a three day trip, that suggests a problem more severe than batteries, so my guess on batteries could easily be wrong too.

My Luxos U battery pack is still functional so I have no desire to start playing around, but I noticed this other posting some time back and noted it in case I need to buy some batteries from an alternative source.
https://www.bikeforums.net/18938859-post19.html


***

I tour with a Sinewave Revolution and an external pass through cache battery, the battery pack was designed and sold for solar power systems, so I can't advise further since I do not tour with my Luxos U.

Good luck.

Maybe it's because it's Friday, but I read the title of this thread as Busch & Miller, thinking, "Heck yeah!"

If memory serves my original E-werk was bought circa 2011 and still works fine.
I've had to replace the external cache battery twice now and due to living coastal, suffered corrosion on one usb type cable.
Sjscycle.com came to the rescue for all replacement items with the usual excellent great service.

I've been so pleased with my E-werk, I bought a second system for my Extra-wheel trailer which too boasts a dynohub.

Research suggested to me that other systems didnt start charging until faster speeds were gained which, being a meanderer of pace, helped determine my purchase.

Best of luck sorting out the issues OP.

Agree with the other posters. The issue is mostly likely the Li-Polymer battery. You can try and replace it; if you can’t find that specific battery you can probably find one from Adafruit or Sparkfun.

I don't think that it's the battery, because the USB-Werk outputs can show voltage for hours after it has been disconnected from the hub. You can see this in the first photo: the 5.03 Volts is coming from the battery. It seems more likely to me that it is the control circuitry that conditions the power coming from the battery.