rx servo power
07-11-2016, 08:03 AM
#3
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I've asked the service folks at Futaba if they have ever seen a RX with a burned up power bus due to current overload.
The answer was "No"
How many amps do you think you will need?? I will also say that nearly every single discussion I have ever seen on this topic significantly overestimates the current demand.
Here's an example: A few different folks have wired up 40% airplanes with 12 to 14 large high power digital servos. Data show clearly that the average amp load runs around 3 to amps with very short (millisecond duration) spikes to perhaps 20 to 30 amps.
People that say things like they have 10 servos with 3 amp stall currents as meaning they need a 30 amp system miss the point that rarely, if ever, will properly installed servos ever see the stall current and the potential for every single servo in your to be stalled simultaneously is between Slim and None and Slim just left town!!
The answer was "No"
How many amps do you think you will need?? I will also say that nearly every single discussion I have ever seen on this topic significantly overestimates the current demand.
Here's an example: A few different folks have wired up 40% airplanes with 12 to 14 large high power digital servos. Data show clearly that the average amp load runs around 3 to amps with very short (millisecond duration) spikes to perhaps 20 to 30 amps.
People that say things like they have 10 servos with 3 amp stall currents as meaning they need a 30 amp system miss the point that rarely, if ever, will properly installed servos ever see the stall current and the potential for every single servo in your to be stalled simultaneously is between Slim and None and Slim just left town!!
07-11-2016, 08:38 AM
#4
My Feedback: (19)
Most modern receivers have multi-layer PC boards so there are multiple traces handling the current load to each servo pin. More important than the capacity of the board is supplying enough current to the receiver through multiple connectors. I use a minimum of (2) power connections to the receiver and up to (4) on large planes with high capacity servos. Silent-AV8R addresses the subject of total draw quite well. As long as you supply adequate power to the receiver through enough connections, the overall current draw of the servos probably won't be a problem unless you somehow stall all the servos at one time which is highly unlikely.
07-11-2016, 09:50 AM
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Yep. I generally try to use larger wire and multiple plugs to feed the RX. That is the choke point in the power system. ALL the power has to go through the battery wires, only some of it goes to each servo.
07-13-2016, 03:45 AM
#6
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I'm building a hovercraft, 4 9g servos, 1 lift motor (ch5), 2 thrust motors (twins on ch3), on a 6ch radio. All 4 servos will be actively moving most of the time as I am taking it through a circuit course.
