Take a look at this product.
http://www.batteryspace.com/compactd...upto50amp.aspx
We used this to tune our minibot motors and it worked out great. Reading the specs I think the analyzer is within your test range. We used this with a variable DC power supply.
Here are some uses:
Set speed control cutoff voltages and currents
Tune performance by comparing different setups of propeller, motor, gearing, speed control and battery
Measure a full battery charge and compare to spec when charger claims done
Check peak currents are safe for battery, speed control, motor, wiring and connectors
Predict airplane flight time based on ACTUAL conditions in your model
Check battery capacity and health and whether battery should be retired
Verify that the minimum voltage under load is within specifications
Check for wiring and connector power losses.
Roy