There are three types of ‘buzz’: (1) After the sensor and the data recorder are connected, two long “di—di” sounds may indicate that the system has begun to work normally. (2) Six hours after wearing, the alarm may sound a long “diii” every 3mins to indicate that the current of the sensor is abnormal; if this is the case, remove the sensor. (3) Seven minutes after implanting, the alarm may begin to sound every 10 seconds, indicates that the data recorder card is not fixed correctly; if this is the case, adjust the data recorder card.