Connecting Lighting to 36v Battery

[faphillips]

I am about to order the Nano kit for a Brompton which currently has no provision for powering lights although there is apparently a spare 36v supply.

My inclination is to fit the Brompton dynamo set but without the dynamo and these would normally accept a 6v supply (I believe). The question is how do I convert 36v to 6v. Is there a compact step down regulator/convertor for this purpose, are they small and is this the right way to do this. Any help would be appreciated.

Another question: Do electric bike controllers get hot in operation(and in particular the Tongxin 36v version)?

Any advice appreciated

FAP

 

[flecc]

The usual way to have 36 volt lights these days is to use high voltage LED bulbs, these being commonly used on scooters(mopeds) and e-bikes. This US site shows the sort of bulbs if you scroll down.

The eZee bikes now have high voltage LED lights, the headlight using a "bulb" integrating a seven LED array, wired in series with a single LED tail light. Both have MES screw caps.

I don't know of any suitable voltage dropping converters offhand.

Controllers can get a bit warm but I've never known enough heat to worry about. I'm not familiar with that controller though.
.

 

[Ian]

Maplins have a range of MES (miniature Edison screw, the type often used in dynamo lighting) bulbs in various voltages but not 36V. One possibility would be to use 3 12V lamps in series from the 36V supply using either 1.2W (stock code WL80B) or 2.2W (WL81C). Note that all 3 bulbs have to be the same though.

Another option is to use a 24V 3W bulb (WL82D) in series with a 100 ohm 3W resistor (W100R), the excess voltage would be dropped across the resistor. This could be repeated for the rearlamp.

Note that most dynamo lamps have one connection linked to a mounting screw as they use the frame as a return "wire". It is necessary to remove this link if wiring in series, and in any case advisable when running off the main battery.

 

[flecc]

I think another important factor is whether there is to be much after dark riding.

The LED lights supplied with bikes are generally only good enough for an occasional use with due care taken.

Most who commute regularly in the dark in winter spend on the very much better accessory lights that are available, whether riding in town or country. Many of these are very high intensity LED lights which can be run from their internal batteries without undue cost, or using rechargeables.

The only snag with those is that they are usually expensive. At the highest point, some cost more than some complete e-bikes.
.

 

[JohnD]

Whats the position now?

I'm resurrecting this thread to see if there is a better solution now.
I have very nice LED lamps fore and aft but these run on batteries - my controller has 'spare' connectors for the ped elec and the brake sensors but no others - it would seem a pity not to use onboard power if it's available but I understand the solution many be more complex than running on batteries!
If I could run a 36v headlamp I would?

What is the collective wisdom?

 

[Straylight]

To go off at a slight tangent, my main light to see by is dynamo powered, and so syphons off a little of the available energy to work (both from me and the motor). The principle advantage being that even if the batteries were flat, I could still see my way home. I'm lucky though, in that my bike came pre-equipped with a Nexus hub dynamo, which gives very little rolling resistance.

 

[Old Timer]

You know, I`ve got some 53 led front lights( cheap Chinese things) I`m actually quite amazed at just how bright they are around the lanes where I live and the Akaline batteries that they run on just seem to go on and on. Of course there are some really expensive lighting set ups around (and as has been stated cost as much as some bikes but to be fair they are generally used by the Lycra brigade who can and want to punch a bike along as fast in the dark as they do in the daytime.

 

[Old Timer]

Please don`t shoot the messenger but these are the lights in question. The front light has three power settings + a flashing setting and the rear has a number of different flashing settings as well as a steady setting.
I always have my lights on when riding during the day so I can say with some confidence that the batteries do last a reasonable time. I suppose you could maybe run rechargables in them but I buy my alkaline batteries from 7dayshop.com 48 at a time and they are cheap enough to not have to worry.

53 LED BICYCLE FRONT LAMP + 5 LED BIKE FLASH REAR LIGHT on eBay (end time 24-Jan-10 19:22:06 GMT)

 

[mutmost]

I have recently installed a dc-dc convertor form this ebay seller

http://www.rc97378.com/ cost about £11 including shipping and I have it currrently wired to a 20w halagon M16 from an old homemade set up. It will output 2 lots of 12v and one of 3.3v, I am looking a building my own for next winter if this holds up until the mornngs are light enough.

 

[flash]

36 volt lights on Ebay

Has anyone any experience of these?


LED Electric Bike Lights for 24V 36V 48V Horn Switch on eBay (end time 08-Mar-10 23:26:26 GMT)



LED Electric Bike Lights for 24v 36v 48v+Horn Switch FS on eBay (end time 25-Mar-10 11:04:06 GMT)