Capacitor For MM 4S

[JeffEmbracedDC]

Three questions.

1. Is 5600 uF completely unnecessary?:

2. Would you lose any performance (other than 2 seconds of runtime) choosing a 5600uF over a 2700uF cap?

3.Also, do we know if these Novak caps are Low ESR?

http://cgi.ebay.com/Novak-Power-Capa...QQcmdZViewItem

-Jeff

[BrianG]

Originally Posted by JeffEmbracedDC

Three questions.

1. Is 5600 uF completely unnecessary?:

2. Would you lose any performance (other than 2 seconds of runtime) choosing a 5600uF over a 2700uF cap?

3.Also, do we know if these Novak caps are Low ESR?

http://cgi.ebay.com/Novak-Power-Capa...QQcmdZViewItem

-Jeff

1. Higher capacitance is usually better for this type of application. However, the heat that comes from these is usually dissipated better if spread out over several caps. Using several smaller caps vs one larger one also helps transient response. And, finding a 5600uF cap rated for 35v would be physically large.

2. You would not lose ANY runtime with caps. Think of caps as short-lived batteries. On the contrary, you may actually gain a very little but I don't want to get into that

Or, the famous water/electricity analogy:

Think of a battery like a water faucet and a large tank of water as a capacitor. Also, think of water pressure as voltage and water flow as current. Resistance would be restrictions in the pipe and whatever the water powering (water wheel maybe).

A faucet never "empties", but it's output flow is limited by pipe size and whatever source feeding it (river/stream/city water works/etc). If you try to pull too much flow then the output pressure will drop.

A tank (cap) needs to be filled, but can supply large amounts of water for a short time. Empty it too much/too fast and it wont be doing anything really.

3: Usually, the higher rated temps (105* +) tell you if it's low-ESR.