DC to DC converter want to trade or help me find one?

I have this DC to DC currently:

33 - 75Vdc in, and 12V, 12v, & 3.3Vdc out



http://cgi.ebay.com/DC-to-DC-Conver...786?pt=LH_DefaultDomain_0&hash=item56309513ea

I'm needing something along the same lines but I want it to be:

10- 30Vdc in (could be higher input voltage as long as the minimum is low enough) and 12v, 9V, 5V & 3Vdc out.

All of these outputs will be run from either 4S or 8S LiPo pack depending on how I configure it so from 14.8 - 29.6Vdc input, however I might be using closer to 12V at some point, so I'd like it to be able to accept at least something near 10-11Vdc and I'd really like it to be all in one unit.

A good friend of mine's father is an electronic engineer and is developing a device that will accept various voltage inputs and put out a steady output from a battery pack in various voltages automatically, however the prototype won't even be ready for use until I'm already on the road on around October 1st.

If there is a really compact, simple and efficient way to modify my current DC to DC converter, I might consider adding this:

12Vdc in to 9 & 5Vdc out

http://cgi.ebay.com/POWER-SUPPLY-12...959?pt=LH_DefaultDomain_0&hash=item563bff0fef

I have now found a DC to DC that will take 24Vdc In and out put 12, 12 & 5Vdc, this is the closest I have seen so far for my needs, and I am thinking maybe the best so far since it even comes with a heat sink attached!

nono, you are not gonna be cycling to montana if you leave october 1st. do not be deceived by this balmy weather, it is already freezing on top. maybe you can get a rideshare off CL with someone who has a rack or truck. rain starts again day after tomorrow.

I decided to go with the last one and take the chance that it might be too much voltage (5Vdc vs 3Vdc) for my tail light. If it is, I will just replace it with one designed for 5Vdc.

Thanks!

dnmun said:

nono, you are not gonna be cycling to montana if you leave october 1st. do not be deceived by this balmy weather, it is already freezing on top. maybe you can get a rideshare off CL with someone who has a rack or truck. rain starts again day after tomorrow.

Click to expand...

He he I appreciate your sentiment, but you must understand, I WANT to ride in the nastiest weather possible this year to prepare myself for a worst case scenario next year in the spring. If I am able to avoid Snoqualmie pass, then I should avoid the most possibly nasty place to have to ride. If it gets too bad, I can always get off and walk the bike.

I have lived in Montana where when the sun goes down so does the temp like a light switch! I'm not saying it's going to be pleasant, sometimes it's going to be down-right nasty! However, it is going to be an adventure! If I get too much snow, or find myself where they are not plowing enough for me to feel safe on the road, I can always take the train/bus home. The whole point is to hit the winder weather prepared and make it through anyway. It's looking like Hwy 12 through Idaho will be a much better path than I-90, and I'd much rather not mess with busy freeways, no mater how large the shoulder may be.

The universal choice is 12v for accessaries. Yes, there are things that demand an odd voltage but all those toys can be had in 12v. Then the only question is which bling will demand the most power and get a converter to cover it. I got my converter from http://www.thunderstruck-ev.com/index.php?dispatch=categories.view&category_id=40 Good luck.

LI-ghtcycle said:

dnmun said:

nono, you are not gonna be cycling to montana if you leave october 1st. do not be deceived by this balmy weather, it is already freezing on top. maybe you can get a rideshare off CL with someone who has a rack or truck. rain starts again day after tomorrow.

Click to expand...

He he I appreciate your sentiment, but you must understand, I WANT to ride in the nastiest weather possible this year to prepare myself for a worst case scenario next year in the spring. If I am able to avoid Snoqualmie pass, then I should avoid the most possibly nasty place to have to ride. If it gets too bad, I can always get off and walk the bike.

I have lived in Montana where when the sun goes down so does the temp like a light switch! I'm not saying it's going to be pleasant, sometimes it's going to be down-right nasty! However, it is going to be an adventure! If I get too much snow, or find myself where they are not plowing enough for me to feel safe on the road, I can always take the train/bus home. The whole point is to hit the winder weather prepared and make it through anyway. It's looking like Hwy 12 through Idaho will be a much better path than I-90, and I'd much rather not mess with busy freeways, no mater how large the shoulder may be.

Click to expand...

You do not want to take Snoqualmie Pass at all friend; WA-DOT has that all tore up right now with a major lane-widening project several miles long. Link: I-90 - Snoqualmie Pass East

~KF

LI-ghtcycle said:

I decided to go with the last one and take the chance that it might be too much voltage (5Vdc vs 3Vdc) for my tail light. If it is, I will just replace it with one designed for 5Vdc.

Click to expand...

Sorry, I didn't see this thread until now.

You can just stick two diodes in series with your taillight. That'd take it down by 1.4V, leaving you at 3.6V. Three diodes brings it down by 2.1V, for 2.9V at the taillight. Depending on the current rating of the taillight, you can put some pretty small diodes in there. for instance, the bridge rectifier diodes out of an old computer PSU.

BTW, if you ever decide to sell that DC-DC, it appears to be just like the one I have on DGA now (from Icecube57), except yours is capable of higher current; it'd be nice to have a spare, or one to use on another bike so that things are more or less the same between bikes. In fact, since that one's current rating is over 4A, I could use *both* filaments of the scooter headlight for extra brightness.

Kewl! Thanks AW, what exactly is a computer PSU? I can't seem to recall ... I think it might have been mentioned in a class when I was young ... but the old gray cells aren't tell'n!

When you say I can put them in series, are there diodes with just 2 legs? Most that I have seen have 3.

Sorry; computer PSU is just hte Power Supply Unit. Even the old 250W AT or ATX style supplies probably have big enough diodes.

Most diodes only have two legs, and look like black resistors with only one white band (that's the negative end). There are three-legged versions, but they typically have two diodes in them, either common cathode or common anode. Flyback or switch-mode powersupplies (SMPS) usually have at least one of these in there, often next to the transistors or FETs used to switch the transformer on and off.

The diodes you're looking for are usually marked 1N400x, where x could be anything from 1 to 7, higher voltage stuff has a higher number, for that series, so the ones you'd find in a PSU input bridge are probably 4006 or 7. Higher current versions are often fatter.

It still might not work, if you have to use three diodes and it drops the voltage too much, unless the DC-DC has an adjust (trim) that lets you raise it anohter 0.1V.


OH, and anohter solution is just get 3 more taillights like yours, and run them in series for 12V operation. It'd be four times as bright, too. :lol:

Sweet! Thanks again!

I will see what I can scrounge out of one of my less usable PSU's I have several computers in storage that I really need to get rid of anyway.