IMU-3C is a rugged, real-time monitoring unit that can detect building seismicity, and is used for detecting and predicting structural damage in buildings, as well as monitoring building structural health. The IMU-3C is suitable for various harsh field environments. In a stable network environment; It can record natural seismicity, vibration data, and control measurement parameters through a built-in 4G or Ethernet remote connection. The IMU-3C supports real-time data stream transmission in Windows and Linux, as well as seismic event threshold triggering, self-testing, remote configuration update, and remote firmware upgrade. IMU-3C is easy to deploy and has an IP68 protection rating. It can operate stably in the temperature range of -40°C to +70°C, and can be used independently without additional equipment. Due to its extreme reliability and cost-effectiveness, the IMU-3C is the best choice for long-term monitoring tasks whether in harsh environments, or in building structure monitoring.