My bike light projects

Hello community,

after reading in this forum I decided to show a few of my self made bike lamps. I posted all the facts and pictures in the german IBC-Forum (http://www.mtb-news.de/forum/showthread.php?t=300808) and my run to a maximum light output started 2007. The first HID lamp (many years ago) was a regular Xenon car headlight with a standard Bosch ballast and a D2S in a small aluminum reflector. The measured (I work at a university and have the possibility to measure luminous flux in a calibrated ulbricht sphere) output of this lamp was about 2400 lm (Pictures are links to the photos uploaded in IBC):
http://fotos.mtb-news.de/p/9891

The next step was a really new thing: I used a 70W Metal halide reflector lamp type Philips CDM-R 70W as bike lieght (http://fotos.mtb-news.de/p/24754). There was no experience about the robustness when riding on a bike with it. But it worked a long time very well (output about 4000 lm) until the next step came. Now it was on the time to break the 10000lm limit. At this flux all the automotive lights -even when overpowered- where too small. After the very good experiences with the 70W metal halide lamp I decided to take a 150W type in a aluminum reflector. At last I built a lot of different 150W lamps (minimum 5 types) with differnt lamps in different reflectors, the 10 klm limit (measured) was reached with overpowering the 150W lamps to about 180W. Here (http://fotos.mtb-news.de/s/35996) are pictures of my newest 150W type with the best beam distribution. The most of my 150W lamps have too much brightness close to the bike what causes a adaption of the eye to the light scatter and you don't see very far. In the link you see the complete system I use very often. The battery is a 29,6V/10Ah 25C LiPo-battery what works about 2 hours at this lamp. The total weight is about 3 kg (the lamp only about 200g), battery and ballast (ballast is a in-house development) are in a carrier bag. This is my brightes really as "daily driver bike lamp" used lamp. After the 150W there has to be a bigger step to a lamp what is not really a daily driver lamp (anyway when there are no better batteries available). I used a Philips MSR575 lamp (this is a standard lamp for big disco effects) in a 100mm aluminum reflector with a specially designed ballast and the from 150W-system known LiPo-battery (now only for 30 minutes runtime):
http://fotos.mtb-news.de/s/13254
This was enough to measure 40000lm at the end.
But then i smelled the limit of 100000lm. First I thougt about a Philips MSR 1200 (1200W metal halide) but the rated flux was too close to 100klm, so I took a Osram HTI 1500W with a rated flux of 165000lm. The sphere at the university is not able to measure this lamp because of the extreme UV and the heat (the possibility of a damage at this measurement is too high), but I'm sure to have the 100klm with this lamp. At last a lamp crash in the sphere will cause costs of several thousand euro.
The reflector is the same type of the 575W, at last the HTI1500 is smaller than the MSR575. The ballst is -what else- especially designed for a 8s LiPo battery (now we are at a runtime of 5 Minutes) and can deliver 600W to 1600W (maximum input power about 1,9 kW). This all at a compact size and with a little bit more than 1 kg weight.
Here you cann se pictures in my IBC album:http://fotos.mtb-news.de/s/36420

But I do not build only HID lamps, there are several LED lamps (very small and compact types too) and also a very light spot with a H7 automotive halogen bulb (http://fotos.mtb-news.de/p/789772).


So you can have a few impressions at my IBC photos.

I hope this is intresting for you -even it is not really expedient stuff...



best regards

Thomas

Hi siamese!

Can you write something about your ballasts constructions?
I'm especially interrested in ~200W unit, for overdriving for eg. Phillips CDM-T 150w and reach ~20k lumens. On your photos I saw very small device, I think it is designed to use directly with 8s Li-Ion. Can it work with hot restrike igniter?

Reards
upek

Hi upek,

for my first lamps (70W and 150W) I used a standard Osram ballast with a simple self made unregulated DC/DC converter (I tested the 230V Osram ballasts with DC and they run from about 220VDC to 400VDC) based on SG3525. Later I tried out the UCC3305 for automotive HID up to 70W powered with 4s LiIon. Later for the high power Lamps I designed my own circuit controlled by a Attiny 85 uC for power regulation. I never tried the new IRS2573 from IR but I think it will be a easy way to design a ballast for several hundered watts. At last I use standard igniters for MH Lamps up to 400Hz lamp current frequency - it works very well.

Best regards

Thomas

Another thing about hot restrike: It is not possible to restrike the standard single ended mh-lamps hot. When you connect much higher voltages than the cold ingnition voltage to the lamp you will have a flshover across the contacts. At last for the more powerful lamps without outer bulb like the HTI1500 hot restrike is not necessary because they cool down in less than one minute. At all when I ride at darkness I always have three lamps at my bike: A dynamo lamp with two cree XR-E (fixed at the bike, not removable and not able to be switched off), one of my more powerful LED-lamps (7xXP-G, 4x MC-E etc.) and a HID with 150W or more. So it doesn't matter when it takes a little time to restrike the HID lamp.

regards
Thomas

Thanks a lot for answers siamese!
Did you use Osram Powertronic ballast? Can you maybe post ballast modification pictures for 180W? Did you try Osram HCI-T lamp? In standard version(4200K) 150w lamp has 14500lm. And how about startup time with standard igniter?
I'm would not to use more than a 250w MH lamp, 15K lm is enough for me
Regards
upek

Hi upek,

I used the Osram powertronic PTU 150 (http://fotos.mtb-news.de/p/435202) but not with 180W, only with standard 150W. The 180W was with a DIY ballast. At the Osram I only changed a 10k resistor to a 47k type inside because at DC operation the 10k became very hot (http://fotos.mtb-news.de/p/435203). The ballast has its own igniter, for the diy types I used standard Tridonic types (the 400W type runs the short time at the bike also at 1,5kW/13Amps lamp current without damamge).

Regards
Thomas

Hi siamese!
Can you write something about your ballast creations? (like this - http://www.mtb-news.de/forum/showthread.php?t=300808&page=27) This is very interresting. 300w ballast powered by 8s Li-ion batterypack will be very small and powerfull for portable lighting. Maybe you have some schematics or ideas to share how to build this type unit?

Thanks!
Regards
Lukasz

The ballast is designed in three parts: First a DC/DC-converter (push-pull converter) with 300-400V output voltage (dependent on input voltage). This works with a efficiency higher than 90%. The next step is the most sensitive part: a buck-converter for the power regulation. In my the power control is done by a attiny85 uC, but the current control is a analog circuit. You have to design the feedback-circuit dependent on the lamp type, the "easisest" lamps to control are small HID like D2S. Efficiency about 85% to 90%.
The last step is a inverter from the regulated DC to 50-400Hz AC reactangulat. The simplest and most efficient step (ca. 95%), but you have to take care about overvoltages and the EMC from the igniter!

What it all makes difficult and absolutely no beginner project is the design of all the transformers (they have to be designed and coiled yourself) and chokes. Also some small mistakes can destroy many expensive semiconductors and your lamp (in the past a inverter got damaged and a ballast had a DC output voltage; after a few minutes the connected CDM-T exploded!).

I would start with the complete IC solutions (see in post 3). At last I don't have any schematics. I everytime design only a board without going the way over a schematic. It takes too much time and is absolutely unimportant for the design...

best regards
Thomas

Here a new video with a comparison of the smaller bicycle light:
http://www.youtube.com/watch?v=ftdXcqKICfU&context=C31bd21dADOEgsToPDskJUxBITnnqYFc9WhW_DTaYo

My next project will be a Osram HTI 400W/D5/60 lamp. I hope to get a very compact and efficient lamp with a good spot. For the friends here of extreme spotlights I would propose the 400W/D3/75. But at last the D5 has a higher efficience and fits better to my ballast (because of the higher arc voltage and lower current; my actual 500W-ballast has a startup current of only 8 amps.

best regards
Thomas

Thomas: Wow!
I can not beleive what you have done!
You could start making bike lights or just do a design and let a company build the lights for you! They would sell better than anything in the market!
It was a pleasure to view your projects! May I say My Friend!
Thanks for listening
TadpolePilot steve