Question about Cycle Analyst v3 and DC power out.

[spisska]

Am I missing something obvious, or am I just stupid and/or misguided?

So I was out at the mad scientist shop this morning when I came across this ridiculously cheap 12V LED tail light. For under $3, I'll take a crack at it, sure. (Note: the link describes this light as having a 24-inch lead, but all the ones in the shop only had a couple inches of lead, and ground is the mounting bolt. Not a big deal, considering the price. They also have this one listed on the site for $4, but I didn't see it in the shop.)

I could swear I remember reading that the DC output port from the CA was part of a DCDC converter that stepped the power down to 12V. So imagine my surprise when I hooked up a meter to this port and found it carrying the full voltage of my battery, which I imagine I do not want to run through a cheap light rated for 12V.

Am I imagining things? Is this port not a DCDC converter? I can't find anything in the CA Setup screens relating to power output down this line.

Is there somewhere I can adjust it, or will I need a 12V converter before I build in a light system?

How does this power source work with lights like the Luminator?

I normally consider myself a pretty clever person, but I feel like there's a key fact in here that I'm missing.

Anybody drawing power out of the CA for lights and/or accessories? If so, how are you doing it?

Thanks.

P.S. Just passed 100 miles today on my first build. Big thanks to everyone here for all the help, and for being part of this fantastic community.

 

[Tench]

Your findings are correct, the output jack on the V3 CA does indeed carry the full pack voltage, the luminator can run on this voltage as it has its own built in dropper.

it is not possible to turn this voltage down via the CA menu.

 

[spisska]

Thanks, this is starting to make a bit of sense to me now.

So I'd need a converter like this one, right? How does this wire up? I see voltage in and ground on one side, and I assume Ctl is control, and unused. I see voltage out on the other side, but what's OV and what's trim? Does ground not come back?

Another question: I've got three or four dead PSUs for desktop computers. These are designed for, among other purposes, putting out 12V DC from a 120/240V AC source. Are there any components in there I can repurpose to use with a ~50V DC source?

Thanks for the help.

 

[drsolly]

I use one of these.

http://www.ebay.co.uk/itm/DC-DC-LM2596HV-4-5-60V-to-3-35V-Adjustable-Step-Down-Power-Supply-Module-/321202601998?pt=UK_Computing_Other_Computing_Networking&hash=item4ac92ac00e

£1.75, will take in 4.5-60V and output 3-35V. Max output power is 15w, which should be enough for most lights.
Make sure you get the kind that does 60v, most of them only do 35v. Very simple to connect up, and then you adjust the output voltage using a pot.

At that price, it probably isn't worth trying to convert a PC PSU (and I'm sceptical about whether that's even possible).

I use another one to convert a 4s Lipo to the 5v needed to power my pda (used for navigation).

 

[Tench]

I have just bought a couple of these, awesome light with a dropper built in!

http://www.ebay.co.uk/itm/Super-Bright-12W-12V-80V-Motorcycle-Electrocar-LED-Light-Headlamp-B5UT-New/331003683468?_trksid=p2047675.c100011.m1850&_trkparms=aid%3D222006%26algo%3DSIC.FITP%26ao%3D1%26asc%3D22046%26meid%3D6206378320150451796%26pid%3D100011%26prg%3D9537%26rk%3D4%26rkt%3D10%26sd%3D261433859294

 

[madnomad]

I've just ordered one of these:
http://www.ebay.co.uk/itm/191304896814?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT
I'll let you all know how it goes when it arrives.

 

[madnomad]

I've just ordered one of these:
http://www.ebay.co.uk/itm/191304896814?_trksid=p2059210.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT
I'll let you all know how it goes when it arrives.

It's rubbish. Don't buy one.