dynamo advice please

[Andre Jute]

Dan't got it covered. The good thing about a sleeve of heat shrink, even two layers, is that it gives you something to grip when you have to unplug the dynamo because you need to remove the wheel. -- Andre Jute

[Danneaux]

Andre,

What I wish for is a molded plastic connector, a la Shimano's dynohub connector. It would make wheel changes so much easier for the SON *if* it could accommodate the double wiring I have for the charging system as well as lighting.

As it stands, I am using 4.8mm piggyback connectors. With those, the piggyback connectors go on the SON tabs, and the other leads go on the subsidiary tabs. The mass can be a bit hard to remove.

I did forget to stress the importance of using a silicone high-dialectric grease on the connectors. Without, it can be a real struggle to get the connectors off the SON tabs. With...a breeze, and the electrical connections are protected from water and corrosion.

Best,

Dan.

[il padrone]

Heat-shrink over the connectors* then mold a body out of Sugru.



http://middleagecyclist.blogspot.com.au/2011/05/pedal-power.html

* you must isolate the connectors to eliminate any chance of short circuit. SON warn that there can be quite high voltage at this point.

[Danneaux]

Heat-shrink over the connectors* then mold a body out of Sugru.

And a very nice-looking result indeed, Pete! I've seen this at Middle Age Cyclist's but wondered how securely the Sugru would bond to the connectors. I pondered using something like JB Weld (my favorite etching polyamide/polyamine epoxy resin) first to ensure the connectors were bonded, then going the Sugru route.

you must isolate the connectors to eliminate any chance of short circuit. SON warn that there can be quite high voltage at this point.

Yes. The voltage can be quite high indeed. The effect is similar to touching an electric fence if your wet fingers happen to ground across the SON poles while spinning the wheel very fast to see if it really happens. It does.

As a kid, I used to test 9-volt batteries by touching the two poles to my tongue. Worked. 

Best,

Dan.

[il padrone]

And a very nice-looking result indeed, Pete!

Yes, a lot nicer than my slightly-bodged fix - the light lead and E-werk lead combined at the connector onto just the two connectors. But it works well.





I've since found out about those piggy-back lead connectors  you're using Dan, that are available for this situation.  A better solution as it allows you to disconnect the E-werk more easily should you wish to.
 

[Andre Jute]

Andre,

What I wish for is a molded plastic connector, a la Shimano's dynohub connector. It would make wheel changes so much easier for the SON *if* it could accommodate the double wiring I have for the charging system as well as lighting.

I use something like this:

Available from here (but be very careful ordering, or you could be stuck for major carriage costs, possibly import/dumping charges, and sales taxes -- VAT -- on the total value including the carriage):
http://www.bmsbattery.com/accessory/439-9pin-waterproof-cable-female-connector-for-motor.html
Seen, with apologies for the photo not being very clear, in my application at:

In which you should note, bottom centre of the photo, that the cable is arranged to enter upwards into the hub below the nut, and to loop downwards before curving back up along the fork. This is by its nature not a very neat installation but it is guaranteed not to conduct water into your hub along the cabling. The cable is permanently attached to the hub, and the waterproof junction you break to take the wheel off is 6-8 inches along the fork, held on above the connector by a tie wrap, and on the lower part by nothing because the cable is stiff enough to be self-supporting. Mine is now arranged to fit behind the fork, out of sight.

Mind you, I've never heard of a SON being damaged by ingress of water, nor the hub I use this arrangement on at the moment, Bafang's QSWXK, but I don't like engineering that is designed to fail, as SON hub junctions can easily be arranged to do, when it is so easy instead to do the job right.

Andre Jute