B-maxx finally finished...pics!

[zeropointbug]

Originally Posted by MetalMan

It's great to hear that the 5s2p A123 setup is working great for you :).

In my Revo, I get spikes upwards of 120amps (MicroPower won't display anything higher) with the 540C 7XL, and that's with a 100,000wt. filled center diff.

120 amps? How come my Micropower is logging 135 amps? Would mine be a newer version? Mine is also acting funny.

My truck is 10 pounds fully loaded.


luvsrc, i have to be honest, you have one of the nicest Revo's going, especially with that Neu is there ;)

I thought my 7XL was going to run hotter than what it is, maybe the current temps (19C) and the finned can is helping, in reference to smooth can Fiegao's. It sure is sick for power though! I can speed along at 30mph and gun it on gravel, it will easily wheelie at speed. I LOVE IT! :027:

[MetalMan]

I have one of the first MicroPowers produced. Yours is V2, right? That would explain why mine won't show anything above 120amps.

[zeropointbug]

Aah, yah I have a V2, I just bought it in January.

I did notice I have less punch with the Eagletree connected though, do you find the same thing?

[MetalMan]

I can't say that I have noticed less punch with the MicroPower, but I'm sure that's how it is. It uses a shunt to drop voltage across, and that shunt has resistance, even if it is small. I don't know if you have felt the MicroPower after a run, but mine gets warm.

[zeropointbug]

i don't know for sure, I was playing around with the settings too, that might have been it, I might have changed the torque dynamics selection to soft. Mine does get warm too after a run. Have you checked out the graph I have of the Eagletree, does that look typical to you for your A123's?

[MetalMan]

It's kind of hard to tell what the specific numbers are with so many minutes worth of data. Would you be able to get a zoomed-in version of maybe 30sec.?

[zeropointbug]

Can you zoom in the graph? That would be really useful, as the graph I have now is kinda general, you know.

I'll make another good run tomorrow, and see how it goes.

BTW, how do you charge your A123's? Do you use a Lipodapter or something, I know there is one meant for them.

[MetalMan]

To zoom in on the graph, you drag from the upper-left corner of where you want to have it zoom in on, and finish at the lower-right corner. To unzoom, you do the exact opposite.

I charge my A123 packs on a "hacked" Astroflight 109. It charges to about 3.65v/cell.
I used to charge my 5s2p packs using a Duratrax ICE in NiMh mode with a LipoDapter.

[zeropointbug]

So, do you do a complete CC-CV charge? For a 5s2p, you would cut off charge at 100mA.

I'm gonna go try that zooming now, thanks.

[MetalMan]

The AF109 charger isn't a CC/CV charger, but it does CC, and then goes into a pulse mode to keep the voltage at the maximum point. The Lipodapter doesn't allow for CV, and only CC.

[zeropointbug]

Didn't think so. That explains why I have 20 mins of runtime and you have 15 min you say roughly?

Also, I don't know if I asked you before, but what gearing are you using? Total reduction.

What temps does your 7XL run at? I managed to get it to 70Celcius (158F) today.

I am just getting my Eagletree calibrated properly now. So I will post a good eagletree run tomorrow sometime, of 30 sec like you requested. I'll zoom in on a spot with a good range of current levels and stuff.

[MetalMan]

The AF109 will still do a 100% charge, it's just that instead of doing a CV phase, it does a pulse phase that keeps the pulses going until the battery doesn't need any more pulses to stay at the max. voltage.

My Revo has a home-made "slipperential" that uses the same gearing as Mike's Slipperential, and I have 20/40 pinion/spur on stock diffs. Total reduction is 12.52:1, and I think I need to use a 46t spur instead, so the FDR will be 14.40:1.
The 7XL runs under 160 deg. F, usually about 140 deg.