jyl

I have a question about wiring up a sidewall dynamo light system. Thanks to the generosity of noglider, who provided this dynamo for my experimentation!

The Miller sidewall dynamo is, interestingly, putting out a steady 12 volts. I could not get a steady amperage reading using my voltmeter, but it is over 0.3 A (because when set on 32-332mA range, my VOM kept reading "over limit"), so I suspect the dynamo is a 12 volt, 6 watt model.

So I am thinking about using two 6 volt dynamo lights, wired in series. I'm looking at the Lumotec "Basic" because it is inexpensive ($17 w/o stand light, $32 w/) at Peter White Cycles, and two would look nice mounted under the porteur rack.



My question is about wiring. I think I will need to use non-conductive mounts, then it is a simple matter of dynamo to the contact of the first light, first light mount/ground point to the contact of the second light, and second light mount/ground point to a ground point on the frame. Correct?

I may not use a dynamo taillight, by the way.

Double0757

I think you would need a voltage regulator. I'm not sure that going series on the lights, would give 6 volts instead of 12?

in case you determine that you need a voltage regulator, you could use an RC voltage regulator that are very small and light.

Good luck! Sorry could not be of more help!

Double O

Double0757

https://batterytender.com/images/series8.gif

It looks like it could work!

I think you would need to do the same for the rear lights! Or use the voltage regulator in the rear if you don't have space for two rear lights!

Picture please!

noglider 

Oh I just realized, @Double0757 is right. Doubling the load doesn't necessarily cut the voltage in half. It might not even come close to doing so.

fietsbob

Halogen bulbs should be found in 12v relatively easily, since the auto biz is all 12v.

match the load the bulb spec, to the Dynamo output specs. want 2 lights, their wattage total would be the dynamos wattage output.



Shopping solution : Peter White may still have a few 12v tail and headlights from the B&M kit to go with their 12v bottle dynamo.

Mr IGH

That may work. All the newer dynohubs float ground from the frame, if the dyno's ground is tied to the frame it may only give 1/2 power to an LED light. With 1/2 power your lights will be dim.

noglider 

@jyl, what did you end up doing for your daughter? She's gone now, so I'm curious to know how you equipped her bike!

jyl

Things got kind of busy and we were buying so much other stuff - computer, mini fridge, bedding, chair, etc - that I just sent her off with the sidewall gen, the single head light and single tailight wired to the gen, and battery blinkies front and rear.

Her immediate need, she says, is for better cargo carrying, so I'm going to get her a Wald basket to zip tie to her porteur rack. Or rather, she's going to the near-campus bike shop to get it. Then she needs to familiar with cycling around the town. There is a local bike class that I'll ask her to attend, and she's going to visit the campus bike coop too.

When we get a sec to catch our breath, I'll finish figuring out the dual light setup and take the parts down and install them. The university is a bit over two hours' drive from us, so an occasional trip is do-able.

In the meantime, I've been working more on my son's bike, since he's riding to school and after school class daily now, and it is getting darker and starting to rain a bit. Installed PDW Full Metal Fenders, an Axiom Road Streamliner rack, and a collapsible Wald pannier basket. Yes, the vintage rat racer is starting to look like a common mule. He has assorted blinkies and a helmet light. I saw him riding home one early evening and I am proud to say he looked a bit like a UFO. Some reflective tape is in the plans too.

noglider 

Bravo, Daddy!