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Kan 400 NiMH 4-cell, twin stick pack – Full charge before each run.
Pack weight = 35.0 grams including shrink wrap, Deans micro connector, and 3″ wires.
Data taken 10 seconds into each run using an Emeter with 20 amp shunt.
GWS LPS RLC 4.8 v motor with 4:1 gearingProp—- Volts— Amps— Watts—Rpm—Thrust(g)— Pitch Speed(ft/sec)
EP-6050 4.98 — 3.18— 15.8—- 6210— TBD— —- TBD
EP-8060 4.66 — 4.82— 22.5—- 4440— TBD
TBD
EP-9047 4.54 — 5.25— 23.8—- 3720— TBD
TBD
EP-9070 4.49 — 5.61— 25.2—- 3360— TBD
TBD
Calculations from Mathcad:
Battery source resistance = .205 ohms (.051 ohms/cell)
No-load battery voltage = 5.63 volts (1.408 volts/cell)
Peak power output = 38.7 watts at 13.75 ampsHi Dick et al,
Looks like this cell goes like hell! Don Srull says it is robust and
tolerates being hot better than most cells. Five or six of them
would do great in a small A ship. Too bad we can’t use 4 of them
in an E-36!Sincerely,
ChuckHi Jim, I just received a 6-cell KAN400 pack from CheapBatteryPacks.com. After the Holidays I’ll run tests and post the results here. Yes, I am planning on building a Class A electric ship. Mine will be about a 40″ wingspan model powered with a MP JET AC 22/7-45D outrunner. Stayed tuned for further details. This plane will also be capable of flying with a 2S lipo battery in the 350 to 400 mah range. It will be a much lighter airplane with this battery, and should serve well as a back-up ship for both Class B electric and F1Q electric.
DickThanks Dick, I am considering a Jay’s Bird from BMJR with a Axi 2208/20. The Axi needs 12 amps. I need a lighter option than the SR500’s. I will watch for your post. Jim
Jim, I have not been able to run tests on the my 6-cell KAN400 pack because I don’t have all of my equipment back from the Florida KOI contest. I’ll explain why later. However, I did a few calculations and I think 12 amps is too much for the KAN400 pack. Take a look at the data in the post above: each KAN400 cell has .051 ohm resistance; so 6 cells totals .306 ohms. At 12 amps the pack terminal voltage would drop to 4.77 volts and the pack would be dissipating 44 watts. The voltage is too low, and the dissipation too high. The battery would get very, very hot. My MP Jet motor will be drawing only 8 or 9 amps, maybe 10 amps at the very most.
If you need a lighter option to SR500’s take a look at KAN700AA NiMH’s. Check them out here: http://www.cheapbatterypacks.com/?sid=372932&pgid=loosecells&chem=NIMH. In a 6-cell pack this battery would be over 30 grams lighter than SR500’s.
DickKan400 NiMH 6-cell, flat pack – Full charge before each run.
Pack weight = 50.1 grams including shrink wrap, Deans micro connector, and 3″ wires.
Data taken 10 seconds into each run using an Emeter with 20 amp shunt.
MP Jet AC 22/7-45D outrunner motor
Phoenix 10 controller
Alum. folding-prop hub with 32 mm pin pitchBlades
Volts— Amps— Watts—Rpm—Thrust(g)— Pitch Speed(ft/sec)CAM 8×4.5– 6.69— 7.04—- 47— 6870
TBD
42.9
CAM 9×5 —- 6.46— 8.12—-52 — 5910
TBD
41.0The numbers are a bit better than expected. The battery can output 52 watts, no problem. The motor and battery do not get hot. A bigger prop may be possible, but I will fly with these props first and see what happens. Not now though, we have 10″ of snow on the ground.
How do we determine the power losses in a pack with a 3.6 amp. load.
I did not realize that is part of the sizing requirements. Never thought of it.Rich
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