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over taxing esc

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Old 06-27-2019, 01:05 PM
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oly 9
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Default over taxing esc

Just got a slow ride from Tower hobby, Went with the recommended servos Tactic minis and encountered a problem. When I operate the servos on the ground going from one the other the esc power quits and browns out the receiver. I have tried 4 escs from different brands and all have a 5v 3a rated output. If I disconnect esc power to the rec and add an aux battery to the rec. the problem goes away. I can operate the servos all day long and no brownout; Has anyone seen these tactic servos overload a system elect. I have many of the Tactic standard size and no problems love them.
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Old 06-28-2019, 05:37 PM
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Similar problem, causes and solutions
Power loss when applying aileron and elevator - RCG

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Old 07-02-2019, 08:29 PM
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Originally Posted by oly 9 View Post
Just got a slow ride from Tower hobby, Went with the recommended servos Tactic minis and encountered a problem. When I operate the servos on the ground going from one the other the esc power quits and browns out the receiver. I have tried 4 escs from different brands and all have a 5v 3a rated output. If I disconnect esc power to the rec and add an aux battery to the rec. the problem goes away. I can operate the servos all day long and no brownout; Has anyone seen these tactic servos overload a system elect. I have many of the Tactic standard size and no problems love them.
Digital servos? High accuracy and torque, but they can draw a lot more current than analog servos, especially if there is drag in the linkages (stall current can be 1A for each servo). Not a "switch mode" BEC (not a UBEC)? The higher the battery voltage, the less total current that they can provide (without overheating). e.g. if using a standard "3A" BEC (rated 2s-4s lipo), the total current capacity with a 3s or 4s lipo will be much less than 3A.
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Old 07-08-2019, 11:54 AM
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What ESC's and how many cells?
With the Slow Ride setup for 3D, the large throws and surfaces are going to result in higher current draw, even without any aerodynamics loads.
If the ESC's have linear 3A BEC's and you're running on 3S, you'e almost certain to have a problem, and 4S is out of the question with most linear BEC's.
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Old 07-08-2019, 06:37 PM
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(UBEC is a propriatery brand name, no info,I prefer LBEC (linear) and switching SBEC (switching), gives more info.)

The higher the power-pack voltage, the fewer servos a non-switching = linear BEC = LBEC can handle. Switching BEC's = SBEC hardly have this restriction.

The higher the battery voltage, the hotter a LBEC will get, for a given current/load/servos.
Or, in other words ...
The higher the battery voltage, the lower the current a linear BEC can supply.

In depth:
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