The ultrasonic surgical device includes a power source configured to generate power, an ultrasonic transducer having a first resonant frequency, the ultrasonic transducer electrically coupled to the power source and configured to generate ultrasonic motion in response to the generated power, an ultrasonic probe configured to be mechanically couplable to the ultrasonic transducer, the ultrasonic transducer and the ultrasonic probe having a second resonant frequency when the ultrasonic probe is coupled to the ultrasonic transducer, and a controller configured to determine whether the ultrasonic probe is properly coupled to the ultrasonic transducer based on the first resonant frequency and the second resonant frequency.