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I hate how they made the factory cooler on these. If the fets were rotated 90deg they could have put a tube down the length of each one. Your design looks good.
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FE BOATING: Less like a hobby and more like an addiction! -
Very cool - but for me and my skills with a solder gun the 2 cap boards that Steven sells are for me.
At $23 & $32 dollars each just easier.We did it with a Bang!
Cats Are Where It's At!Comment
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Is this it John? I saved this comment from Dr. Wayne in my "Extra caps" doc.
Low esr capacitors draw masssive amounts of energy on recharge
When there are a large number, the recharge can create a nanosecond EXTREME energy draw ... fortunately the wire between battery and cap may act as a buffer and reduce shock to the battery... it's why some cables get hot in stressed setups.
Higher capacity / more caps increases this risk of battery failure due continuous peak/excess discharge.
Too many caps can have an adverse affect on performance and longevity of components.
Id not exceed 3300uf for 25C5000(125A cont).. or 6400uf for 45C5000(225A cont ) for a high draw setup
shorter battery cables is better than a big bank of caps to compensate.
use voltage rated caps at least 30% higher than your batts.
eg 35V for 6S ... 63V for 12S.. allows head room for spikes.
regs
Wayne ...
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Wayne Schutte PhdCSE BaSE BaEE. Australian, and damn proud of it. !Comment
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Proper cap banks use rubycons for a reason. They have around 5 times lower esr than the ones you are using. High esr caps are inefficient and heat up a lot more and will fail quicker.Comment
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Really !!! I read the Data Sheet on these caps before purchasing them - - have you ???Comment
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.103 ohms it looks like. 63v rubycon same vale is .023Comment
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Apples & Oranges
The graph I've provided shows the general characteristics of any capacitor. Specific types will exhibit different levels, which are also dependent on a Boat Load of other parameters.
The data provided by the various capacitor manufacturers varies:
Rubycon rates the resistance (in Ohms) of capacitors as Impedance (Z) at 100 kHz [100,000 cycles per second].
Cornell Dubilier provides MAX ESR (in Ohms) at 120 Hz [120 cycles per second].
It would simplify matters if they were all playing off the same sheet of music.
Generally, the ESR level of an Aluminum Oxide Electrolytic capacitor that's been rated at 120 Hz will decrease by a factor of ~ 4 (Etched in Ice) at 100 kHz.
In my limited exploration concerning this subject, I've found that one Expert (sic) will consider the information provided by another so-called Expert … GARBAGE (put mildly). One Super Genius, willing to make a 100% commitment, might be able to resolve this issue to everyone's satisfaction - - HAW!!!
So, if anyone wants the Real Skinny on capacitor bank performance, purchase several hundred thousand dollars worth of diagnostic equipment, acquire the expertise to utilize it correctly, test your configuration, then formulate your own conclusions. Lots O Luck !!!Comment
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