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Excessive Current Draw?

Old 07-16-2002, 03:21 AM
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Location: Collierville, TN
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Default Excessive Current Draw?

The Morris 60 SuDoKhoi in my Avitar seems to flatten a battery in no time.

Specs are as follows...

Weight 7 pounds.
Aileron Servo's (2x) JR2721's
Elevator and Rudder JR4721's
Throttle JR537
Receiver JRPR549
Receiver Battery JRPB4440 1800Mah (NEW)

I have atleast 40 degrees of throw on each of the control surfaces in high rate but mostly fly slow or hover in low rates except for elevator. Normally I have the flaperons on most of the time.

After approximately 40 minutes flying time receiver voltage is down to 4.7/4.8 v checked immediately after landing. This equals 4 flights usually.

I had a 2000Mah Nickel Metal battery in the plane as built but flight times degraded to about 1/2 hour. I cycled the battery to get a good idea of its capacity and it was pretty short (1/2) of capacity. I then replaced the battery 2 weeks ago with the 1800 sub-c pack.

I patterned the battery for 24 hours @ 100mA and immediately cycled. It's capacity was around 1600 mA. I have been flying for a couple weeks now with this new pack, always checking voltage before each flight.

Total flying time always run around 40 minutes before reaching the lower voltages.

Tonite after flying this afternoon I cycled the battery down to see what the remaining capacity was. It cycled with about 580mA. This was down to 1.1v per cell. I think I did the right thing to quit after four flights.

Is my new battery pack doing what it should?
Does the 2721's or 4721's draw that much more current than the standard 517's or 537's.

I have other fun fly planes that I can fly for 80-100 minutes with 1200mA packs using R700's and 5x 537's.

Thanks in advance!

Old 07-16-2002, 01:00 PM
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Location: Champaign, IL
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Default Excessive Current Draw?

They will draw a little more power, since they are higher performance. I would generally think you would get a little more than that for battery life, but it is not extremely bad. There is a possibility that a problem servo could cause drain in the battery. Sending them in, or swapping them would be about the only way to find out. Otherwise, maybe after using the pack for a little while maybe it will improve.

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