I need MAJOR Warrior help - RC-Monster Forums

Serum · 03.13.2006, 01:25 AM

The controller is powered by the 4 AA's and the steeringservo can take a lot of power from them. the ESC takes his share too.

BrianG · 03.13.2006, 12:48 PM

I'm just trying to follow along here and am a little confused.

When you say you were running AA's, does that mean NiCD/MH, or regular Alkalines? IIRC alkalines have a steady dicharge curve so the voltage drops steadily as they are discharged. Plus, they don't like high currents too much as opposed to NiCD/MH.

Second, were you running the built-in BEC at the same time as the AA's? The Warrior manual says you can run an Rx pack to help bolster the BEC for higher currents (I personally wouldn't do this), but not if those AA's are Alkaline.

jagboy · 03.13.2006, 08:32 PM

Yes... the AAs are alkaline. I know NiMhs are better and I really wish I had some, but I dont have $20 for a pack. And yea, I ran it w/ the BEC because the manual said it was good to do that.

JB

BrianG · 03.13.2006, 09:06 PM

Quote:

Originally Posted by jagboy

Yes... the AAs are alkaline. I know NiMhs are better and I really wish I had some, but I dont have $20 for a pack. And yea, I ran it w/ the BEC because the manual said it was good to do that.

JB

The manual does says it's ok to hook an Rx pack to the BEC, but I'm not sure if they meant Alkaline Rx packs. Most of the time, people use NiCD/MH batteries for their Rx pack. If the BEC voltage exceeds the battery voltage (even by a little) on your Alkalines, the BEC will try to charge those batteries simply because there is a difference in voltage between the two. When the Alkalines were new, they probably measured a little over 6v so the BEC was fine since it was at 6v. As soon as the batts dropped below 6v, it probably tried to charge the batts. As you know, you aren't supposed to charge Alkalines (unless they are specifically meant to be recharged). According to Wikipedia, recharging non-rechargeable batteries can cause cell explosion. Although, if the current is low enough, it might just heat up. Either way, it's "bad". Is it possible that your BEC component became overheated in this scenario? I don't know how this would effect the other components or cause something to come loose...

jagboy · 03.13.2006, 09:38 PM

Hmmm... good to know. But what about nimh? They definately dont stay at 1.2v /cell. Say halfway through the pack they measure 1.1v. If the BEC is putting out 6 and the Rx pack 5.5, wouldnt that stress the BEC current too? It obviously wouldn't be bad for the batteries. The alkalines were in fine shape when I took them out, so I'm guessing they weren't damaged. O well... I'm done w/ this problem. I'm sending it off to Mike ASAP. I am sick of having a many multi hundred dollar savage sitting on my desk w/o an ESC.

JB

BrianG · 03.13.2006, 10:17 PM

Well, not really because the BEC won't let the Rx pack get that low. As soon as the Rx pack voltage drops even a little below the BEC voltage, there will exist a difference in potential and current will start to flow and will start to "trickle charge" the Rx pack. The net effect is that the battery probably won't drop below the BEC voltage much.

Honestly though, I wouldn't even use the BEC because it's just that much more heat for the ESC to dissipate on that little heatsink, which should be reserved to cool the ESC output devices. Personally, I would just disable the built-in BEC. Then you can use any Rx pack type you want.