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WHEN TO USE A CAPPACK IN YOUR AIR OR SURFACE SETUP

WHAT IS A CAPPACK?

A CapPack or Capacitor pack is a bank of capacitors that are electrically wired together to form what we would know as a pack. It can be useful in brushless motor applications where it serves to give just that little boost needed to overcome ripples in the battery voltage caused by hard acceleration or long battery wires. Ripple voltage is extremely hard on an ESC - adding the CapPack can help reduce the load on the controller's on-board capacitors. The result would be prolonged lifespan of your ESC.

In general, ripple voltages should always be less than 10% of the total pack voltage, and the smaller the ripple voltage the better. If an application exhibits more than 10% ripple voltage, you should consider using higher discharge (C Rating) batteries, shorter wires, higher current connectors, better gearing or a smaller load. Castle Creations X-series, Copperhead 10 and Phoenix Edge ESCs feature data logging, which has the capability to report the ripple voltage they encounter during use.

WHAT SETUPS WOULD BENEFIT FROM A CAPPACK?

Helis: CC CapPack is highly recommended for all 500 class and smaller heli applications where Y harnesses and long wires can bleed voltage, and hard collective pulls can strain even the most powerful batteries.

Surface Vehicles: With their high torque requirements – going from 0 to 100% throttle isn't easy on controllers or batteries - RC cars and trucks put enormous loads on brushless power systems. Use CC CapPacks in high performance applications (IE drag racing and high speed runs) to help your system power through the abuse.

Fixed Wing Aircraft: Larger electric power systems lead to larger electric powered aircraft, and sometimes the distance between the battery pack and the ESC grows beyond the length of the wires installed on the components. Adding wire also adds inductance, which can increase the ripple voltage in a system. CC CapPack essentially negates the ripple caused by the addition of up to 12 inches of length to the battery wires.

QUICK FACTS ABOUT CAPPACKS

  • Multiple CAP PACKS may be used in an application. 

  • CAP PACKS should be installed as close to the ESC as possible.

  • CAP PACKS will add capacitance to a setup and will therefore increase the snap that occurs on plug-in.

  • Installation of CAP PACK(s) in a brushless setup will not make a poor setup into a good setup, nor will it (they) compensate for batteries that are unable to deliver the amps demanded by the load. The CAP PACK product is intended solely to compensate for minor voltage loss across wires.

  • A cap pack does not add any additional voltage to the system because caps are charged by the system battery, so they only charge to the batteries' voltage level. They do not increase ESC or motor performance; they are used to protect the ESC from damage caused by excessive ripple. If you have an incredibly good battery, you may not even need a cap pack because it won't have enough voltage sag to cause excessive ripple voltage.

HOW DO I KNOW WHAT CAPPACK TO PURCHASE?

Honestly though, there is no magic equation for picking the right cap pack because every setup is a little different. Ripple voltage is mainly dependent upon the quality of your batteries; but can also be affected by the quality of the solder connections, battery connector size, and motor load. The better your batteries, the less ripple voltage you will have and the less capacitance you will need to fight your ripple voltage. You could have two exact same setups but with different quality batteries and the one with the better batteries will have lower ripple voltage. Therefore that setup will need less capacitance than one with lower quality or less healthy batteries. The best thing to do is to look at your data logs and make the assessment based upon the level of ripple you are seeing in the real world.

Castle offers three CC CapPacks, one is rated for up to 12s and two (with different units of electrical capacitance)are rated up to 8s. The 011-0002-02 and 011-0148-00 install parallel to the battery wires; 011-0165-00 installs perpendicular to the battery wires.

INSTALLING A CAPPACK

The installation of a CapPack requires some basic tools and a high-power iron and solder. A helpful video from RC Physics below is worth the watch, great tips! A link to written instructions can be found right here.

If you have questions or comments about CapPacks, and feel free to contact us at : https://home.castlecreations.com/contact-us

If you find yourself needing a CapPack in one of your setups, feel free to use the coupon code “CCCAPPACK” to save 15% on our website!

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