... size, switching signal output For alarm system, proximity switch etc. . Ultrasonic sensor1.TU-001 Ultrasonic sensor consists of a single transmit & ... distanceAfter connecting Vcc and Gnd to power, Keeping the sensor aiming at the obstacle and to be a fixed distance ... a relay, buzzer directly, or connected to a alarm system to active a alarm or action also. special mini ultrasonic sensor, useful sensors