Difference in capacitor configuration

AI Thread Summary
Connecting capacitors in different configurations can significantly affect circuit performance, particularly in terms of time and resistance. The discussion emphasizes the importance of measuring resistances and calculating network impedances to determine the best configuration for specific applications. For lower frequencies, using short, thick conductors is recommended to minimize resistance. The user is working with sizable 1400pF doorknob capacitors and braided 8 gauge wire, indicating a focus on maintaining low resistance. Ultimately, the choice of configuration should align with the desired capacitance and resistance characteristics for optimal circuit performance.
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Hello!

I am working on a project at the moment and I have the option of connecting my capacitors in a number of different ways. My question deals with the possible difference in time, resistance to my circuit depending on where I connect the leads. What I really want to know is if there will be a significant difference in performance between each of the configurations.

For simplicity, I have attached an illustration made in Paint (forgive me please). The capacitors are connected in parallel.

The configurations are listed from easiest, to the least-easiest. Of course there is not much of a difference from the easiest to the least-easiest, however I do believe that this is good information to know.

Thanks!
 

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I think the best way to find out is to estimate or measure the resistances of the connections, and work out the different network impedances yourself. Depending upon the application, you will then see whether it makes a difference or not.
 
Remember that resistance in parallel adds reciprocally, whereas capacitance in parallel adds directly; resistance in series adds directly, whereas capacitance in series adds reciprocally. So as an overall rule for your network, where you increase capacitance you decrease resistance, and vice versa. You may want to work toward an optimum product of capacitance times resistance, or generalized RC time constant for the circuit.
 
Are you in the MHz range? If so, you must provide much more detail.

For lower frequencies and large caps, the technique I've always used is to strap the caps together with very large, very short, conductors. I've even used stranded braid. If you do that, the question is moot.

If these are small caps on a board, simply minimize lead length.
 
Thank you vanesch and Loren Booda for your replies!

TVP45 said:
Are you in the MHz range? If so, you must provide much more detail.

I have not calculated the exact value yet, however it will likely be on the order of a couple hundred Khz. They are pretty sizable doorknob capacitors, at 1400pF. To connect them I am using braided 8 gauge wire (aka, car battery jump cable). I can list off much more precise details as needed. Thanks!
 
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