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How to wire two BECs on a 2x 5S lipo setup

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Old 10-20-2017, 09:38 PM
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Flyboywbl
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Default How to wire two BECs on a 2x 5S lipo setup

Hello,

I decided to convert my BUSA 1/4 scale Nieuport 28 to electric and I was wondering how to wire up the BECs. It has two 5S lipos in series and there is no BEC on the ESC I want to have two RXs. One for half the controls and one for the other half. I would also like to have two BECs. One to run each RX. Im trying to figure out how to wire them so each lipo powers a different BEC. Is this possible or should I just run one off the mother bats in series and have a separate RX pack for the second RX?Any ideas?

Thanks!

-Matt
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Old 10-21-2017, 05:38 PM
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jim billings
 
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Question Two Receivers

Two 5S lipos means a big motor, brushless most likely. The motor will require an ESC to drive it. An ESC that robust will probably have a BEC of five or so volts capable of 5 or more amperes.
A solution to your query would be to use a Y-cable to connect the receivers to the BEC. Designate one receiver to control the motor and cut the signal wire to the other receiver. Both receivers will get power from the same source. The designated receiver may then be wired to half the controls while the other receiver may be wired to the other half controls.
Question Why would you want to split the controls between two receivers? Both receivers process the same transmitter signal.



Jim B.
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Old 10-21-2017, 07:18 PM
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I was thinking for a rundundancy system Incase one receiver went out. So you have 1/2 elevator on each reciver the throttle on one. One aileron on each and the rudder on one. That way if an RX went out, you would
still have half your controls. The other reason I thought about doing it would
ne to put a second reciver and battery in the top Wing so that there were no wires running to the fuse.

The motor is a Turnigy G160 245kv brusless motor. A Hobbywing Platinum HV 100A ESC (can handle up to 12S). But it does not have a BEC so I will have to add one.
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Old 10-22-2017, 09:20 AM
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When a receiver craps out, there is no telling how the servos attached to it will react. Worst case would be an aileron and an elevator at non-zero positions. Successful control using the other receiver would be impossible.
Your best bet short of some pretty sophisticated electronic circuitry is to use a six volt, 2400mAh NiMH or LiFe battery pack and a single receiver. If you are interested in sophistication (which would be appropriate for a two or three thousand dollar plane), I can provide a few circuits for you to peruse. I (and I suspect other hobbyists) don’t recommend it for the Nieuport.

Jim B.
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Old 10-22-2017, 07:57 PM
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I think I figured out what I want to do. Two RX’s ois overkill. I’ll just run a BEC off the battery.

thanks

-Matt
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Old 10-23-2017, 09:04 AM
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Propworn
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On large energy systems I like to fuse my batteries close to the cells. This helps protect all of the electronics in case of any problems even a crash. I prefer running an individual receiver pack for the controls, usually life generation receiver batteries. Even if the fuse were to pop I would still have full control. I have found the BEC usually robs some from the the cells resulting in a few less RPM if it means anything to you.

Dennis
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Old 10-23-2017, 09:11 AM
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This will be overpowered to begin with. So I’m not too concerned about loss of power
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Old 10-23-2017, 11:46 AM
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BECs have been known to fail Hobby King I've seen a few personally just stop working for no reason. Make sure to wire in the BEC before any fuse so if it does go you still have power to the receiver. With batteries powering the receiver you don't have to rely on electronic components to control the model. Bigger models=bigger costs=bigger holes in the ground.

Last edited by Propworn; 10-23-2017 at 11:50 AM.
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