Knowing the operating conditions of a gear system is important to its durability and longevity. When the maximum specified system load is exceeded during the operation, there is a possibility of a complete system breakdown. In this paper, a single spur gear system was used by applying three different loads to simulate changes in operating frequencies. Three loads and four rotational speeds have been applied to the gear system, representing three load levels, simple, medium, and high. Vibration is measured by a 3-axis sensor, "MPU-6050", via the Arduino connection, in which the acceleration is measured in the X, Y, and Z directions in two stages. The first stage is done by taking measurements of the frequency in normal operation and comparing them to the operation with the loads in the second stage. The FFT function converts the acceleration signals produced by the sensor in the time domain into Hz frequency signals with the software "SigView". The results clearly showed the direct effect of increased loads on the rotary gear system by increasing the operating frequency values. The increase in frequency resulting from the increased load applied to the system was associated with the increase in the rotational speed. The results showed that the frequencies are increased by about twenty percent when placing high loads with high rotational speed, which reflects negatively on the entire system.