Finally got me an Eagletree Data Logger!

[BrianG]

These loggers do log higher than their rating, but I strongly suspect they lose accuracy/linearity much beyond the rating. If you zoom in on a ~120A peak, you will probably see the slop estart to round off. That's not typical if you look at the peaks under the 100A rating. So, the real peaks are probably much higher than you think they are if you extrapolate the curve. Also, if you calculate cell resistance over various current draws, you will be able to get an idea of the real current and see if it matches the graph.

I've logged over 140A peaks on a CRT.5 using a Medusa 36-50-3300 on 3s geared fairly conservatively. So I imagine the peaks on the 8th scales are well into the 200-300A range.

Oh, and my 150A version uses 12GA wire from what I can tell.

[sikeston34m]

Originally Posted by BrianG

These loggers do log higher than their rating, but I strongly suspect they lose accuracy/linearity much beyond the rating. If you zoom in on a ~120A peak, you will probably see the slop estart to round off. That's not typical if you look at the peaks under the 100A rating. So, the real peaks are probably much higher than you think they are if you extrapolate the curve. Also, if you calculate cell resistance over various current draws, you will be able to get an idea of the real current and see if it matches the graph.

I've logged over 140A peaks on a CRT.5 using a Medusa 36-50-3300 on 3s geared fairly conservatively. So I imagine the peaks on the 8th scales are well into the 200-300A range.

Oh, and my 150A version uses 12GA wire from what I can tell.

Yes, thanks for pointing that out about the graphs. On "spikes" over 100 amp, the top is flattened out, or chopped off looking. The closer to 120 amps the peak gets, the flatter it gets. Hmmmm.........

Peaks under 100 amps are very sharp. They look like ice picks.

The 150 amp version is bound to be better than this, at least for 4S setups.

With a Higher Voltage setup, Amp spikes should drop back into the measureable realm, I would think. But that does all depend on the setup.

What is the Highest Amp Logger out there? One that's capable.

[sikeston34m]

The setup got changed around again.

This time, with the goal of getting amp draw down to a decent level while maintaining a good level of performance.

The setup is:

E Revo
MM Pro (lowest timing, 100% punch control)
5S 20C 5000mah Turnigy
Medusa 36-70-2000 geared 14/52 (around 35mph)

This setup performs well. Top Speed sees the motor spinning around 38000rpm.

I tried this setup on 4S (Top Speed 28mph), and the graph from it is almost identical to the 5S Graph. Hmmmmm.......... I wonder what it would do on 6S? Don't have the 6S setup at the moment, but it does have me curious.

Most of the spikes are right around 65-70 amps. This should be accurate for the logger since it isn't exceeding 100 amps.

[sikeston34m]

I just acquired some Apogee 3S 3800mah packs. So far, they've been pretty impressive.

The Limn chemistry doesn't hold the voltage under a load that the Turnigy's do, but they come out of the run pretty cool.

This 6S setup is making over 2100 watts!

E Revo
MMM ESC
Medusa 36-70-2000kv gearing 14/52
Apogee 6S 3800mah

They came out of this 20 minute run just barely warm and resting at 3.7 volts per cell.