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5 11-Jan-2016, 10:50 PM (This post was last modified: 19-May-2017, 07:46 PM by Oscar.) I have been hearing of issues with LittleBees burning up cameras and VTx because of active braking sending surges up the power lines. I am recommended putting a 1000uf 16v capacitor across the main power input where your vTX connects as this keeps those surges from killing your components.
I'm curious how will a capacitor at the main power input control voltage if the surging is happens within the PDB? Does the cap absorb the surges and helps regulate the entire PDB? I’m not sure how that works?
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17 My guess here.
The ESCs are usually fed from the battery directly and therefore the surges may occur in the main power line, affecting everything connected in parallel (PDB, separate BEC, vTx fed directly from the battery).
The capacitor between the battery and consumers or between the battery and all the ESCs achieves necessary filtering of said surges.
Since you feed the ESCs from the battery and not the PDB, there should be no surges on PDB's output.
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0 what capacitor would you use ?
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17 As capacious as possible for desired size, as the cut-off frequency is proportional to 1/C, and we want reaction to spikes as little as possible. But that's from the point of view of control theory, I'm sure there are some electronic nuances.
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0 Many thanks guys.
My friend got the same setup and burned his fpv cam now I can direct him to check out here.
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6 13-Jan-2016, 06:08 PM (This post was last modified: 13-Jan-2016, 06:19 PM by David Trounstine.) For 4s setups a 16v 1000uf cap should be enough. They are relatively small too.
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16 I just ordered a bunch of 1000uF 16v capacitors. I'm hoping to use them on my quads. I think it's better to use 32v caps. I'm just wondering what would happen if there's too much voltage for the 16v cap?
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34 01-Sep-2016, 10:08 PM (This post was last modified: 01-Sep-2016, 10:09 PM by oyvinla.) I normally put 4x470uf 25V caps on my setups. one on each ESC. Remember to get low ESR capacitors
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17 Adding a cap on the main battery lead won't hurt.
Just add a 470uF or higher low-ESR cap rated for 35V. Solder it in parallel to your main battery lead, while ensuring correct polarity.