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BrianG · 09.08.2007, 07:46 PM

A member here (AAngel IIRC) got a bunch of these caps a while back and sold some in small amounts. Whatever you get, make sure they are low ESR types otherwise they will heat up badly and blow. Look for ones specifically spec'd as low-ESR (Equivalent Series Resistance) and 105*C or higher temp value.

35v is a good value to get for 5s. Generally, you pick a voltage that is ~35-50% higher than the max ESC voltage for longevity and reliability. 5s is 18.5v. 50% higher is 27v. So 35v is perfect. You can use higher voltage caps but they get physically bigger.

For the capacitance value, using multiple lower value caps is better than one large one. The current and heat is distributed more evenly among them and multiple ones have a better transient repsonse. So, if you want 1000uF total, it's better to use three 330uF instead.

As to where to find them, Mouser electronics or similar large parts suppliers will have them. RadioShack does NOT have them. If you use lesser-quality caps, they will overheat from the AC ripple and blow/pop.

	(#5)
BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	09.08.2007, 07:46 PM A member here (AAngel IIRC) got a bunch of these caps a while back and sold some in small amounts. Whatever you get, make sure they are low ESR types otherwise they will heat up badly and blow. Look for ones specifically spec'd as low-ESR (Equivalent Series Resistance) and 105*C or higher temp value. 35v is a good value to get for 5s. Generally, you pick a voltage that is ~35-50% higher than the max ESC voltage for longevity and reliability. 5s is 18.5v. 50% higher is 27v. So 35v is perfect. You can use higher voltage caps but they get physically bigger. For the capacitance value, using multiple lower value caps is better than one large one. The current and heat is distributed more evenly among them and multiple ones have a better transient repsonse. So, if you want 1000uF total, it's better to use three 330uF instead. As to where to find them, Mouser electronics or similar large parts suppliers will have them. RadioShack does NOT have them. If you use lesser-quality caps, they will overheat from the AC ripple and blow/pop.