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In this section our staff has taken the time to answer some of the most common questions about radio controlled vehicles. If you have a question and do no see it answered here please feel free to email us or give us a call at (608) 222-8846.
What's the deal on LiPo (Lithium Polymer) Batteries?
LiPo batteries are new to the hobby but are becoming more popular. They charge differently than older Sub-C batteries. Unlike Sub-C batteries that stop charging once thier voltage peaks, LiPos must be charged in CC-CV (constant current then constant voltage) and on the proper charger and the proper settings.
What are S P and C ratings? S stands for Series, this is the number of cells that are in series in the battery. This determine the max voltage of the pack and the charger settings. For example if you have a 3S pack, it is 3 cells in series which is 11.1 volts. How do you get 11.1 volts? Each cell is a nominal 3.7 volts, so the nominal pack voltage is 3x3.7 or 11.1 volts. Also you need to set your charger to LiPo 3S.
P stands for Parallel, this is an older term that is not used as much anymore. The more useful value is the mAh (capacity/size) of the battery. An example of a 2S2P battery is the Orion 7.4volt 4800 mAh battery. It has 2 cells in series and 2 in parallel for a total of 4 cells. This can become confusing, so the P values is usually omited now.
Which brings us to C ratings. C ratings are used to tell you how fast you can charge a pack and how fast you can discharge a pack. A general rule of thumb is to charge at 1C. What does that mean? For a MaxAmps 6000 mAh pack what 1C means is that you can charge the pack at 6 amps. You should charge the Orion 4800 at 4.8 amps.
What does 10C continuous, 20C for 30 second and 30C busrt mean? These are how much current you can discharge the battery at. A battery like the Orion 4800 could safely dischage continuously at 10C or 48 amps. A MaxAmps 6000 battery rated at 20C for 30 seconds could dischage at 120 amp for 30 second. Burst ratings are usually the max discharge a battery can provide for less than 5 seconds. The Orion pack can supply a burst amp draw of about 144 (48x3).
How fast do they go?
Cars and truck go between 10 and 50 mph
Airplanes fly between 15 and 70 mph
Boats usually go between 10 and 35mph
The fastest custom built Hobby grade RC vehicles can exceed 100 mph!
What is a brushless motor?
A brushless electric motor is just that, it has no brushes. The commutation is done electronically so they require special ESCs (Electronic Speed Controller). Brushless motors will last for years with only a few drop of oil on the bearings once in a while.