Cicatrix Build Diary

[Max]

Lol

What language is cicatrice in? Google translate says it's French for scar

[Anttazz]

Latin originally, but it can be used in English too

[Max]

Ok then, frendo or suggillo or Contribulo or livor all mean to bruise in Latin

[PJ-27]

What's the most you ever lost on a coin toss? Frendo..

[Anttazz]

Right, trying to run this BW off of 2 different voltages, one esc on 7.4v and the other on 14.8v from 2 2s lipos. Can I just do this by wiring both batteries up to one esc and only one of them to the other or will discharging them at different rates make them upset?

[psycho_fling]

lol you love to have different speedos in one bot different voltages lol

purely a statement no help i know :P

[Anttazz]

I do like making them complicated yes .

Cicatrix worked best when it was at its most complicated though, so sticking with that theory. With any luck it should be a lot simpler this year though.

[RogueTwoRobots]

I can't talk from experience (more just what I remember reading on here) but I think the different discharge rates aren't advised. Although if you balance charge each pack separately I don't think it should make much difference but again, I can't say for sure.

What about just having your 14.8V operating voltage and then using either tx or esc functions to limit the travel (dual rates etc) so that the component running at 7.4V isn't seeing the full voltage?

[typhoon_driver]

You are correct Jamie, it is bad to have cells in series with different tap off points for different voltages. Main reason being is that certain cells will become more discharged than others. The ones with the lower discharge then have to take up the slack so to speak to keep the whole system operating and they will try and charge the higher discharged cells. Not a great situation to be in.

Mind you, a while back as a last minute resort I had to use a combination of A123 cells and nicads (basically what I had left) to get hornet 2 back into the arena. It worked but I was just waiting on the smoke rising out of the battery compartment. What probably helped was that the whole system ran on the same voltage, no tap offs anywhere.

[Anttazz]

Cheers guys I thought as much.

All the cells I am using are the same, two 2s 1500mAh lipos so battery chemistry wont be an issue, its just the discharge rates. Its a Sabertooth 10a I want to limit, so i'll have a look and see what all the dipswitches do on it as I dont think the radiolink gear that robot is using will have anything fancy going for it like duel rates. Suppose I could go low-tech and just physically limit where the sticks can go with a chunk of plastic if it comes to it?