Ultrasonic Sensor Outputs

Senix ultrasonic sensors provide a variety of simultaneous measurement outputs including; analog output consisting of varying voltage or current signals, switch output which consists of ON or OFF signals and serial data output using RS-232, RS-485 or ASCII.

1. Analog

Analog outputs are voltage or current signals that vary proportionally with the measured distance. Some ultrasonic sensor models provide two or three simultaneous analog outputs. The analog distance endpoints are easily set anywhere within the sensor’s measurement range. Either endpoint can be the analog high limit or analog low limit, allowing either a positive or negative slope. Standard analog output value selections include 0-10 Volts Direct Current (VDC), 0-5 VDC and 4-20 milliamps(mA) current loop. Computer configurable models permit user-entered analog high limit and analog low limit values.

ultrasonic sensor analog output limits and values

The figure above shows an analog 4-20 mA current loop output scaling. A target is shown detected at about the midpoint of the current loop analog range, which yields a sensor output value of 12 mA.

2. Switch/Relay

Switch outputs turn ON or OFF at a distance setpoint and are used to start and stop external actions or indicators at those distances. Senix ToughSonic sensors have one or two simultaneous switches depending on the model. Each is independently adjustable.

Computer configurable models allow the switches to turn ON and OFF based on defined hysteresis ranges. Switches can also be set ON or OFF only when a target is within a specified switch window. The hysteresis feature allows a single ultrasonic sensor to perform a complete control function, such as managing a pump based on established rules to maintain a liquid level within defined limits. The switch window feature allows proximity sensing only within specific distance ranges.

3. Serial Data

Most Senix sensors are available with either RS-232 or RS-485 serial data interfaces using the industry standard Modbus protocol. Modbus allows two way communication of control instruction and data transfer.  SenixVIEW configuration software uses Modbus over a serial data communication for sensor configuration, monitoring sensor performance, and testing.

Serial RS-232 is an electrical interface used for single sensors that communicate to computers, displays or other user equipment over relatively short distances.

Serial RS-485 interface allows multiple ultrasonic sensors or other RS-485 devices such as digital displays or loggers to be connected to a common communication network. It is more robust than RS-232 and allows far longer communication distances.

Senix ToughSonic sensors can also be set to stream ASCII characters at each measurement, a one-directional communication useful in some applications.

For detailed descriptions on how to use various sensor outputs, please refer to your product manual or contact Senix Customer Service.