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RC Lander 90mm 12-blade unit not performing as expected - Help!!!

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RC Lander 90mm 12-blade unit not performing as expected - Help!!!

Old 08-21-2013, 05:01 PM
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Default RC Lander 90mm 12-blade unit not performing as expected - Help!!!

I'm relatively new to larger High power EDF setups, all of my experience to date has been with 70mm 1000 watt or less setups and they always worked as expected.

I just acquired an RClander 1000kv 90MM 8s-10s setup specs below


8S version (LEDFDPS/MBS90-1A10)
Rotor size..........90mm
Motor...............B4074 /1000kv
Power...............8S / 29.6V
Max RPM...........37,000
Max Watt..........2,800W
Cont.Watt.........2,550W
Amps................82A (up to)
Thrust..............3.6kg (up to)

I have the unit in a Freewing Eurofighter using a Castle Ice2 HV 80 on 8 cells.

I've flown it 4 times and it just wasn't performing as expected. As a matter of fact, I've seen videos on youtube of the same plane flying the stock setup which seemed to have more punch.

So, I've picked up an eflite watt/amp meter and tested the power output. Heres what I am getting.

2x 4-cell Nano-Tech 5000mah (series) 25 - 50C
Max Amps - 64
Max Watts 1720

Nowhere near the 82A 2200+ watts I should be getting.

Now I'm looking to get suggestions as to possible reasons why.

Heres a few things I've considered

1. Batteries - The batteries are not new. Possibly they are not perfoming. Is the C rating to low for this setup? I have some 65c nanotechs on order.

2. Watt Meter - The eflite watt meter has 12awg wire which is definitely lower gauge than the batteries and the esc. The meters wires are getting quite hot during the test, possible this is causing a bottleneck? Can anyone suggest a heavier duty meter? Keep in mind, however, that when I run the system up with no meter, it does not sound or feel like it is performing any better.

3. Wire length from ESC to Battery. The battery lead from the ESC has been doubled in length in order to reach the battery compartment. 12awg wire was used here (not done by me). Is it possible that the extra 5-6 inches of lower gauge wire is choking the system of power?

Any suggestions at all would be appreciated. I really want to get this setup working closer to its spec.


Thanks!
Old 08-21-2013, 06:47 PM
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1 yes, old batteries can be problematic, and even fresh new batts of any brand have trouble supplying an actual 20c for more than about a minute.
2 probably not the problem.
3 yes, can be part of the problem.

never looked at the eurofighter, but long tight intakes, if it has em, will also lower your installed output.
a bad or poor design tailpipe can be detrimental to performance as well.
Old 08-29-2013, 09:29 AM
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Originally Posted by mongo
1 yes, old batteries can be problematic, and even fresh new batts of any brand have trouble supplying an actual 20c for more than about a minute.
2 probably not the problem.
3 yes, can be part of the problem.

never looked at the eurofighter, but long tight intakes, if it has em, will also lower your installed output.
a bad or poor design tailpipe can be detrimental to performance as well.

looking at your watt meter numbers, it indicates your lipo cells are droping to a average of 3.35 volts per cell , going by the amps and watts you are getting. This indicates the batteries are not up to the job at all.
Good batteries will hold a much higher voltage , and that will give you the higher watts and amps
Old 08-29-2013, 03:03 PM
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I believe that setup should be change to a 10s. The 8s is the marginal rating. It is similar to manufacturers stating that a plane can fly on a 40-60 engine. You'll never be satisfied with the lower spec power.
Old 09-12-2013, 11:54 AM
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My nano-tec batteries were junk after 30 cycles and have been sold to others not needing so much power. My new lipos are from www.dinogylipos.com and have almost twice the power from the same old worn EDF unit

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