Ultrasonic Sensor Outputs

Senix ultrasonic sensors provide a variety of simultaneous measurement interfaces, including voltage and current analog outputs, switch outputs that can be ON or OFF, and a serial data interface (RS-232 or RS-485) used by SenixVIEW software or user applications.

1. Analog

Analog outputs are voltage or current signals that vary proportionally with the measured distance. Sensor models have either two or three simultaneous analog outputs. The analog distance endpoints are easily set anywhere within the sensor’s measurement range, and 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 VDC (Volts Direct Current), 0-5 VDC and 4-20 milliamps (mA) current loop.

Using SenixVIEW software, analog functions and responses can optimized using custom end point values (1-10 VDC, for example), setting the high or low output value at power-up, the target-lost response, and a target-lost time delay. Some analog features are also adjustable using the “teach” push-button.

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.

Switches can be turned ON and OFF at different distances. A single switch output can perform a control function such as managing the liquid level in a tank by turning a pump or valve on or off at specific levels. Switches can also be set ON or OFF only when a target is within a specified switch window, allowing a single switch to set an alarm output for a high level, low level, or both.

Using SenixVIEW software, switch functions and responses can optimized using adjustable ON and OFF time delays, initial power-up states, hysteresis and window modes, and loss of target states with an associated time delay. Each switch output can be set to “NPN” type (sinking) or “PNP” type (sourcing) for universal compatibility. Some switch features are also adjustable using the “teach” push-button.

3. Serial Data

All Senix sensors have either an RS-232 or RS-485 serial data interface that uses either the industry standard Modbus protocol or a simpler ASCII streaming output. Modbus allows two way communication of control instruction and data transfer.  SenixVIEW configuration software uses Modbus for sensor configuration, monitoring sensor performance, and testing.

Serial RS-232 is an electrical interface for single sensor communication with computers, displays or other user equipment over relatively short distances.

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

Senix ToughSonic sensors can also send unidirectional ASCII characters (“ASCII streaming”) after each measurement, useful in some applications.

Communications baud rate is adjustable from 9,600 to 115,200 baud and proprietary features are available for high speed data collection in multi-sensor applications.

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