Motor and ESC
IMPORTANT THINGS TO CONSIDER WHEN
INSTALLING AND OPERATING YOUR
MODEL AIRPLANE’S ELECTRIC POWER SYSTEM
In order to help promote safe electric power system operations, maximize our customers’ enjoyment of the hobby/sport of radio-controlled model airplanes, and to minimize the chance of ever experiencing an electronic speed control (ESC), motor or battery failure, we invite our customers to please consider the following ‘tips’ as you install and operate your airplane’s electric-power system:
- Never extend the wires between your battery and ESC. Extending the battery wire can damage the ESC. Instead, if you need greater distance between your battery and motor, only extend the 3 wires between the motor and the ESC; never extend the 2 wires between the battery and the ESC.
- Always carefully check battery polarity every time you connect your battery: If the battery is ever plugged in backwards, even for a brief instant, the ESC will very likely be damaged and may fail shortly thereafter.
- Always use a current meter and a thermometer to check the current and temperature of your electric power system to ensure operation is within safe limits whenever you install a new electric power system and every time you change your propeller. Never operate your electric power system at or very close to the motor’s and/or ESC’s maximum ratings for current, power, or voltage. Doing so will contribute to the generation of excess heat. If there is a heat problem, try using a smaller propeller, then check the current and temperature again. A motor or ESC damaged by excess heat is not covered by warranty.
- Always only briefly raise the throttle just enough to confirm operation and observe the direction of rotation when you need to test your electric power system’s connections and/or your motor’s direction of rotation and when there is no propeller on your motor. Never run your motor without a propeller at full throttle. Doing so may melt the motor’s insulation due to a lack of sufficient air flow, and/or the motor’s magnets might be loosened from a too-high centrifugal force on the motor’s housing. When such damage has happened, failure may not be immediately apparent, but will certainly decrease the life of the motor and could even damage the ESC. If any of the wiring inside the motor or external to the motor develops a short circuit (such as from running your motor at full throttle without a propeller or because of a poorly insulated connection), the ESC will likely be damaged.
- Never allow a short circuit between any of the motor’s wires. The ESC will be damaged if any of its 3 wires connected to the motor are permitted to touch for even a very brief moment while the ESC is throttled up. If these wires touch, it is as though the motor suddenly demanded "infinite" current, causing the circuitry inside the ESC to immediately overheat.
- Always close your throttle before your propeller gets forcefully stopped – such as happens during a crash or if the airplane ‘noses over.’ If your throttle is not fully closed, a high current is suddenly demanded by the motor if the propeller gets stopped, which could be enough to damage the ESC. (NOTE: A damaged ESC may burn ‘open’ quickly, removing the load from the battery and the motor, and they both safely survive; in some cases, the damaged ESC can form an internal short circuit that can damage the motor and might even damage the battery.)
- Always check your motor if your ESC ever fails. It is possible for a motor to be damaged by an ESC; it is also possible for a motor to be the cause of an ESC’s failure. Using a quality ohmmeter, check all combinations of the three wires on your motor, two wires at a time, to confirm that each pair measures very close to the same resistance. Although different sizes of motors have different values of resistance, the resistance between any 2 of any motor’s wires should differ by no more than a few percent. Also, carefully check to be sure that no foreign object has gotten inside your motor and that the motor’s shaft rotates freely on its bearings.
Happy landing and fly safely!