In this paper, a home automation system model was constructed with purpose to investigate of the correlation between the performance of wireless communication, power consumption of the constrained IoT devices and security. The series of experiments were conducted using sensor nodes connected to Arduino microcontroller and an RF 433 MHz wireless communication module. Measurements of the execution time and power consumption of the Arduino during data transfer with different security levels, as well as the analysis of the experimental results, were performed. The results show that the lifetime of the IoT device is determined by the communication speed, sleep mode management and depends on encryption. The obtained results can be used to minimize the power consumption of the device and improve communication efficiency. The results show that applied security reduces the productivity and lifetime of the sensor node not significantly. © 2019 IEEE.