Futaba receivers and Diamond D 4.7 servos
07-23-2008, 05:30 PM
#1
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Join Date: May 2007
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Futaba receivers and Diamond D 4.7 servos
I have Futaba R617FS and a Futaba R617FS receivers and am running Diamond D 4.7 servos. I want to run the servos directly off my two cell lipo pack. I connect the signal wire to the receiver and the red and black power connectors to the battery. The servos will not work! What am I doing wrong or will this setup just not work with Futaba receivers?
07-23-2008, 05:35 PM
#2
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Join Date: Apr 2008
Location: So Cal
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Well for one...you just fried your servos by pumping 7.4V into them. Next you want to look into what is called a BEC which will power your servos directly from the pack while regulating the voltage.
Castle creations, Sport BEC, uBEC, etc.
EDIT:
Although I have been reading they take up to 9.6v? WOW that is a lot for such a small servo! I hope that it is a lot faster than .14 at that voltage...if it can in fact take that anyways...I have my doubts.
Castle creations, Sport BEC, uBEC, etc.
EDIT:
Although I have been reading they take up to 9.6v? WOW that is a lot for such a small servo! I hope that it is a lot faster than .14 at that voltage...if it can in fact take that anyways...I have my doubts.
07-23-2008, 05:50 PM
#3
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Originally Posted by SkunkyMagoo
Well for one...you just fried your servos by pumping 7.4V into them. Next you want to look into what is called a BEC which will power your servos directly from the pack while regulating the voltage.
Castle creations, Sport BEC, uBEC, etc.
Castle creations, Sport BEC, uBEC, etc.
07-23-2008, 05:58 PM
#4
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Location: Neenah Wisconsin
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2S Lipo (2-cell Lipo in series; 7.5-8.4 volts) is also not good for your radio-receiver. Standard voltage for servos and receivers is about 4.8-5 volts (4-cell nicad or nimh). Some "standard" receivers will tolerate 6 volts (5-cell nicad or nimh). A few low-voltage, micro-receivers will work with a 1-cell lipo. Many micro-servos will not tolerate 6 volts (smoke escapes). Whenever you use a 2S or higher-voltage lipo to power the Rx and servos, you will need a separate, voltage-regulator (e.g. the Battery-Eliminator-Circuit in the Electronic-Speed-Control) to power the Rx and servos.
D47 servos will work fine with a Futaba Rx, when the voltage to the Rx and servos is regulated to 5 volts.
D47 servos will work fine with a Futaba Rx, when the voltage to the Rx and servos is regulated to 5 volts.
07-23-2008, 06:13 PM
#6
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07-23-2008, 06:22 PM
#7
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Originally Posted by rcmark
I have Futaba R617FS and a Futaba R617FS receivers and am running Diamond D 4.7 servos. I want to run the servos directly off my two cell lipo pack. I connect the signal wire to the receiver and the red and black power connectors to the battery. The servos will not work! What am I doing wrong or will this setup just not work with Futaba receivers?
You should be able to drive the servo with the 2S lipo by joining the connector to the servo as follows: red wire from servo-connector joins to battery positive (red). Black (brown) wire on servo connector joins to Rx minus-pin. Signal wire on servo connector joins to Rx signal-pin.
