A tractor-trailer truck driver friend often delivers to companies that do not have a fork truck or loading dock. She wants to install a lift-gate on her trailer so she can load and unload her truck without a fork truck. The lift-gate has a 5000 lb. lift capacity and a 3 horsepower, 12.0VDC motor that operates the hydraulic pump. The FLA of the motor is 200A. The motor will be located 80 feet from the generator on the engine. The 80 feet of cable length includes the coiled umbilical cord between the cab and the trailer. Because of the high current draw of the motor, the lift-gate cannot be operated by just a battery i.e. the battery voltage is too low. The engine will have to be running so the voltage source is the generator. The generator Vis is 14.4V. The Rs of the generator is 0.0089ohms.
1. Using an appropriately sized copper cable based upon NEC ampacity (HO 15 for 90 C cable), calculate the voltage at the motor.
2. Calculate the source voltage
3. Calculate what standard size copper cable will give us 12.00V at the motor
4. Check your cable size determination
5. Calculate the gross and net power generated by the generator