WORLD-BEAM QS18U Ultrasonic Sensors Datasheet Miniature Ultrasonic Sensors with TEACH-Mode Programming Fast, easy-to-use TEACH-Mode programming no potentiometer adjustments Ultra-compact housing One discrete output: NPN or PNP, depending on model Two bi-colored status LEDs Rugged encapsulated version for harsh environments Choose 2 meter or 9 meter unterminated cable, 4-pin Euro-style or 4-pin Pico- style QD connectors (either integral or with 150 mm pigtail) Wide operating range of 20 C to 60 C (13 F to 140 F) Temperature compensation Configurable for normally open or normally closed operation Fast response time (15 milliseconds) WARNING: Not To Be Used for Personnel Protection Never use this device as a sensing device for personnel protection. Doing so could lead to serious injury or death. This device does not include the self-checking redundant circuitry necessary to allow its use in personnel safety applications. A sensor failure or malfunction can cause either an energized or de-energized sensor output condition. Models Models Sensing Range TEACH Option Cable Supply Voltage Output QS18UNA Integral push button or NPN remote TEACH (IP67, NEMA QS18UPA 4-wire, 2 m PNP 6P) 50 mm to 500 mm (6.5 ft) cable 12-30 V dc (2 in to 20 in) QS18UNAE Remote TEACH (epoxy- NPN with shield encapsulated, IP68, NEMA QS18UPAE PNP 6P) Only standard 2 m (6.5 ft) cable models are listed. For 9 m (30 ft) shielded cable, add suffix W/30 to the model number (e.g., QS18UNA W/30). A model with a QD connector requires a mating cordset. For QD models: For 4-pin integral Euro-style QD, add suffix Q8 (for example, QS18UNAQ8). For 4-pin Euro-style 150 mm (6 in) pigtail QD, add suffix Q5 (for example, QS18UNAQ5). For 4-pin integral Pico-style QD, add suffix Q7 (for example, QS18UNAQ7). For 4-pin Pico-style 150 mm (6 in) pigtail QD, add suffix Q (for example, QS18UNAQ). Principles of Operation Ultrasonic sensors emit one or multiple pulses of ultrasonic energy, which travel through the air at the speed of sound. A portion of this energy reflects off the target and travels back to the sensor. The sensor measures the total time required for the energy to reach the target and return to the sensor. The distance to the object is then calculated using the following formula: D = ct 2 D = distance from the sensor to the target c = speed of sound in air t = transit time for the ultrasonic pulse To improve accuracy, an ultrasonic sensor may average the results of several pulses before outputting a new value. Original Document 15 July 2014 119287 Rev. I 119287 WORLD-BEAM QS18U Ultrasonic Sensors Temperature Effects The speed of sound is dependent upon the composition, pressure and temperature of the gas in which it is traveling. For most ultrasonic applications, the composition and pressure of the gas are relatively fixed, while the temperature may fluctuate. In air, the speed of sound varies with temperature according to the following approximation: In metric In English units: C = 20 273 + T C = 49 460 + T m/s ft/s C F units: C = speed of sound in meters per second C = speed of sound in feet per second m/s ft/s T = temperature in C T = temperature in F C F Temperature Compensation Changes in air temperature affect the speed of sound, which in turn affects the distance reading measured by the sensor. An increase in air temperature shifts both sensing window limits closer to the sensor. Conversely, a decrease in air temperature shifts both limits farther away from the sensor. This shift is approximately 3.5% of the limit distance for a 20 C change in temperature. The QS18U series ultrasonic sensors are temperature compensated This reduces the error due to temperature by about 90%. The sensor will maintain its window limits to within 1.8% over the -20 to +60 C ( 4 to +140 F) range. NOTE: Exposure to direct sunlight can affect the sensors ability to accurately compensate for changes in temperature. If the sensor is measuring across a temperature gradient, the compensation will be less effective. The temperature warmup drift upon power-up is less than 7% of the sensing distance. After 5 minutes, the apparent switchpoint will be within 0.6% of the actual position. After 25 minutes, the sensing position will be stable. Sensor Programming Two TEACH methods may be used to program the sensor: Green/Red Yellow/Red Teach individual minimum and maximum limits, or Power/Signal TEACH/Output Strength LED Use Auto-Window feature to center a sensing window around the taught Indicator LED position Push Button The sensor may be programmed either via its push button, or via a remote (IP67 models only) switch. Remote programming also may be used to disable the push button, preventing unauthorized personnel from adjusting the programming settings. To access this feature, connect the white wire of the sensor to 0V dc, with a remote programming switch between the sensor and the voltage. Figure 1. Sensor Features Programming is accomplished by following the sequence of input pulses (see programming procedures). The duration of each pulse (corresponding to a push button click), and the period between multiple pulses, are defined as T: 0.04 seconds < T < 0.8 seconds 2 www.bannerengineering.com - Tel: +1-763-544-3164 P/N 119287 Rev. I