BlarneyHammer

I have a SON (Schmidt's Original Nabendynamo) hub, as well as a Tout Terrain The Plug, and I've tried using them on a previous tour. I've heard nothing but good things about them both before and after, but it didn't seem to work for me. I had to be going about 16 mph before the plug would reach a wattage that would charge anything, and even by the end of a day, it didn't appear to add anything to my power bank. Some days, after riding for eight hours, the power bank had less charge than it did in the morning!

I get the idea that the wiring was faulty from the beginning, but after the tour was over, I tried re-wiring the thing again and could never get it to work right. But if you take everything off and simply spin the hub and connect it to The Plug, or to a headlight, it works. Notably, one of the wires that goes up through the head tube is fraying, presumably from rubbing against the starnut.

Any-a y'all have a similar experience and know what might be wrong? Maybe I need a power bank that's less picky about charging at low wattage? Or maybe I need to go to a different shop where they'll set it up right?

Tourist in MSN

A USB charger on a dynohub rarely puts out more than about 500 milliamps (half an amp) while riding at typical touring speeds.

If your powerbank is a big one with many thousands of milliamps of capacity, it could take many hours to put a noticable amount into it.

Occasionally but not often, plugging in a device with a micro USB to charge it can cause it to discharge. I have generally blamed the micro USB plug for this. It is quite rare, but has happened to me.

I am an engineer, although not an electrical or electronic engineer, still I learned some basics of power systems in school. I often use an ammeter when diagnosing such things. You can buy a really cheap one on Ebay, shipped from China (might take a month for shipping), do a Ebay search for "usb charger doctor". Then do a sort to put the lowest price (with shipping) at the top, then select buy it now. Get the gray one, not blue, the gray is impossible to read on a sunny day, but almost readable on overcast days, the blue one is much worse. That will tell you what is coming out of the USB port while you are charging something, both volts and milliamps.

Some devices, especially Apple devices can be very picky on the power supply. If I recall correctly, The Plug has a cache battery, so that usually helps a lot. But some devices pretty much need to be charged from a power bank, then charge the power bank from the USB charger on the bike.

Good luck. I am leaving for a 5 day trip (trying out a new bike), so if any questions I won't respond for a while.

Mr IGH

Are you using the frame as one of the two conductors? The dynohub must be wired with discrete wires for both sides of the dynohub output. If you use the frame as one of the two conductors for the dynohub you only get ~40% of the power output.

BITD when dynos ran lightbulbs the frame could be one of the conductors. With modern LEDs and electronics, there's a diode bridge, if the frame is used as one of the conductors the full bridge turns into a half bridge.

edthesped

I don't have the Plug but do use a Sinewave Revolution and Forumslader and ride between 13 and 16 MPH, with the sinewave I get a little over 12% charge per hour on my cell phone, 2013 moto x. The Forumslader has an integrated power bank that I've yet to see drop below 97% charge and using it the same phone charges at roughly the same rate. As an aside I use my phone as a speedometer so the screen is always on while I ride. I have two dynamo wheels, one has a SP PD-8 and the other an SP PD-8X dynamo.