Welcome to the Forum; nice to have you aboard!
the green light on the plug 2+, when under load, goes on for a few seconds then off for a few seconds no matter how fast I am going. Is this normal or do I have some kind of problem?
You also mentioned...
With no load it stays on from a fairly slow speed as you describe.
Simon, you've done a great job describing the problem. Cutting to the chase, it sounds like your TTTP2 is behaving normally, but your connected device is drawing too much power. Read on for a fuller explanation and some suggestions on how to overcome the problem...Yes, under no load, the TTTP2 should come on with a solid green light from a low speed. This means it is operating normally, there are no breaks in the wires, and it is producing a nominal 5vdc +/- 0.2vdc and is ready for charging. This makes me think your unit is operating properly
.However, the blinking green light under load indicates the device being charged has power requirements that exceed what the TTTP2 can produce. More and more devices (particularly smartphones and tablets) will charge from USB 5vdc/0.5A power (when the device is off, and charging will take longer), but draw far more than that when operating. Recent devices will charge in about half the time when powered by a 5vdc/1.0A wall charger...and take twice as long when charging from a 0.5A USB-standard computer port (same as provided by TTTP2). I suspect this is your root problem, and the TTTP2 just cannot produce the power needed to actually operate your device. If this is the case, you can still charge your device if it is powered off, then after it is charged sufficiently, you can turn it on and operate it from its internal battery when and as needed. Some smartphones take a *lot* of juice to operate.
Overall, there's a range of causes and solutions, and I'll list them below.
Some cost nothing, others are more expensive...1) All these bicycle-mounted charging devices are out in the weather, and so are subject to corrosion
. Anything that increases the electrical resistance of the connections can reduce the capacity of the charging unit, so check for any frayed wires, dirty connections, or surface rust
. Along those lines...
a) Very light surface rust can form in/on the USB port; a quick swab with 90%+ isotropyl alcohol
should remove it and leave a better connection.
b) Though I don't recommend it at the USB port (it is messy and can transfer to clothes), I highly recommend use of a high-dialectric silicone grease at the hub connections at at the cord-to-TTTP2 head cap terminal connection
. This greatly reduces the possibility of corrosion, and makes disconnecting the hub leads a breeze.2) If you have a voltmeter, it can be helpful to check if the TTTP2 is actually producing the proper voltage at the USB port
. When testing, wires 1 and 4 (left to right, looking at the USB port) are the ones that provide power.3) For maximum charging, the TTT2 (like other such devices) really should be used alone
, meaning when your lights are *not* also running. Yes, the power draw for LED lighting is minimal, but if you have a high-draw/high-drain device connected, available power can be marginal, and this could explain why you are getting an overdraw/intermittent power indication under load. If the lights have been on while charging, try turning them off and then check the behavior of the green light.4) If your device does draw too much power for the TTTP2 to charge reliably, then there are a number of solutions...
a) Ride faster
. I'm not being facetious; because the output of the dynohub increases with speed (they are unregulated), the power produced at low speed may be sufficient under no- or low-load conditions but inadequate for high-draw/high-drain devices. Try connecting your device and then riding along at, say, 15mph/24kph. This can often solve the problem...except it can also be a speed higher than you wish to maintain.
b) If this proves to be the case, then you will need to consider adding the Tout Terrain PAT
(Power Amplification Technology, or "ExtraPower") cable. This does not increase the actual voltage produced by the TTTP2, but it does lower the speed at which maximum power is produced. The order would be dynohub > PAT > TTTP2 > USB cable > charged device.
c) Another solution, either with or without the PAT is to use your device with a buffer battery
. The order then would be:
dynohub > TTTP2 > USB cable > buffer battery > USB cable > charged device. The idea here is the TTTP2 can trickle-charge the buffer battery, which can supply either greater voltage, greater current, or both to the device being charged...more than the TTTP2 could produce on its own. Of course if you power your high-draw/high-drain device all the time, the buffer battery will eventually run down, but in practice, what happens is the buffer battery is charged continuously, then is drawn-down only as the device being charged is used. Some buffer batteries can be pre-charged from the mains before use or topped off periodically from a household electrical outlet, so you start out ahead of the game. High-drain appliances like laptops/netbooks/tablets intended for use in camp benefit from a buffer battery that can be trickle-charged with a day's riding; the battery then powers them in the evening and the cycle starts anew the next day.
A buffer battery also provides an uninterrupted, continuous flow of power, so sensitive devices like GPS units and cellphones done's enter hibernation mode when you stop at an intersection and the dynohub momentarily stops producing power. Without a buffer battery, you risk losing data/tracking/satellite acquisition with a GPS or you cellphone goes to sleep. In either case, having to restart them manually can be an annoyance, so the buffer battery helps there as well as helping supply an adequate amount of voltage and/or current to the device being charged or powered.
As a final check, try charging your device with a different USB cable
. These things vary widely in how well assembled, and the soldered connections can be pretty iffy, showing evidence of cold or disturbed joins, which greatly affect electrical resistance. Similarly, check your dynohub connectors to make sure they're in good shape and routed properly.
I always solder mine to the wires, using the crimp tabs to secure the insulation as is proper to relieve strain on the wire strands. I then cover the spade terminals with one or two layers of heat-shrink tubing to provide a good electrical insulator and protect the connection from weather. I've seen problems occur when the dynohub electrical connection terminals are set vertically. A better way is to set them about 7 or 8 o'clock when viewed from the right side of the bike, and route the wires so the spade connectors approach from below. This forms a "drip loop" to prevent water from running down the wired and directly into the connection. The same practice applies at home when routing electrical transmission or telephone lines outdoors...you want the water to drip off, rather than run right into the terminal connection.A couple of remarks and additions before wrapping this up:
1) Tout Terrain have recently revised their installation and operating manual. The latest version is available as a PDF here: http://www.en.tout-terrain.de/fileadmin/media/pdf/deutsch/dokumentation/bedienungsanleitungen/Anleitung_tout_terrain_theplug_06_2012_web.pdf
2) The "Plug 2 Plus" referred to on the Tout Terrain website is the The Plug 2 with the addition of the PAT cable.
3) According to the chart on the Tout Terrain website (and my own experience), The Plug produces a full 5vdc@.5A at about 18.75kph/11.65mph. The Plug Plus (The Plug with the PAT) produces the full 5vdc@.5A at about 13.75kph/8.54mph.
I hope this helps. If you're still having problems after trying the above solutions, give a shout and I'll see what I can do.