Basic wiring: front light and USB charger. Advice needed.

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Samurray
Posts: 37
Joined: 31 Jan 2012, 11:34am

Basic wiring: front light and USB charger. Advice needed.

Post by Samurray »

This may seem like a simple - dum, even! - question but I do not want to make a mistake.
I have the following set up
Shutter Precision PD-8 Hub Dynamo
http://www.sp-dynamo.com/8seriesdynamo%20hub.html
Philips Saferide 60 front light
http://swhs.home.xs4all.nl/fiets/tests/ ... nzicht.jpg
Sinewave Revolution USB charger
http://www.sinewavecycles.com/products/ ... revolution

The Philips Saferide has two pairs of cables hard-wired to the inside of the light. One pair is connected to the SP hub and working fine. I have yet to mount the USB charger though as I'm not certain of how to wire it apart from the fact that I believe it needs to be in parallel to the light. Is it perfectly OK to connect it - using suitable connectors and heatshrink of course - to the other pair of wires coming from the Philips light?

Any advice muchly appreciated :)
tatanab
Posts: 5033
Joined: 8 Feb 2007, 12:37pm

Re: Basic wiring: front light and USB charger. Advice needed

Post by tatanab »

The second pair of wires is to connect a rear light and inside the front light they are connected to the "bulb" side of the switch. If you were to connect your charger to these wires it would only be connected to the hub dynamo when the light is switched on - not what you want at all.

Just break into the pair of wires that connect the hub to front lamp and I imagine all will be well. Unless you can be sure that you would always unload the charger when switching on the light I would put in a 2 way switch with the centre to the hub, one side to the lamp and the other to the charger. To avoid any problems with "earth" you could use a 2 pole switch which from a wiring viewpoint would give a neater job.
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[XAP]Bob
Posts: 19793
Joined: 26 Sep 2008, 4:12pm

Re: Basic wiring: front light and USB charger. Advice needed

Post by [XAP]Bob »

I have a multiway setup:

Dynamo -> Distribution box (a small project box on the dynamo mount on the rear triangle)

Switched power to the rectifier and ReeCharge unit (waterproof micro toggle switch)
Direct feed to rear dynamo light, with a switched takeoff available to power a trailer light instead
Feed to switch on derailleur post* to turn on/off the front light.

This gives me all sorts of combinations, but always with the rear light on...

Basically: Take power from both directly from the dynamo - add switches if desired.


* Note that the switch for the front light needs to be vandal resistant - as it it I've broken mine again, and so it's not switched.
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
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BeeKeeper
Posts: 1265
Joined: 29 Apr 2011, 6:45am
Location: South Devon

Re: Basic wiring: front light and USB charger. Advice needed

Post by BeeKeeper »

You really need to be able to remove the SineWave charger from the bike when not required otherwise you risk having it stolen if it is permanently connected. The German USB-Werk and E-Werk devices do a similar charging job but have a simple connector so they can be removed. Items 5 & 10 on this page would do it: http://www.starbike.com/en/busch-and-mu ... wwodmoIAxQ

Depending where you live it might be easier to look round for some sort of waterproof low voltage connector.

As already stated above you need to connect your charger into the wires coming out of the hub.
Samurray
Posts: 37
Joined: 31 Jan 2012, 11:34am

Re: Basic wiring: front light and USB charger. Advice needed

Post by Samurray »

Thanks all for the suggestions and advice.
I do intend making the Sinewave detachable using quick release connectors with heatshrink. I also wish to keep it as simple as poss at this stage so I'll just wire it straight to the hub along with the front light and have a break in the Sinewave cable to allow for the quick release.
Best
edocaster
Posts: 475
Joined: 10 Apr 2013, 10:43pm

Re: Basic wiring: front light and USB charger. Advice needed

Post by edocaster »

I didn't want to break into my front light wires, so just paralleled the extra pair of cables straight to the hub. Downsides are there's more cable down the fork leg, and a thicker wad to stuff into the hub connector (although you can buy piggyback connectors for some hub spade connectors).

I second the other suggestions not to hardwire the USB charger. My non-light cable from the hub terminates in a connector near the stem, so I can plug in whatever I need on a temporary basis.
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