Wired Connections

Senix ultrasonic sensors include several interfaces that respond concurrently to sensor distance measurements, i.e., after each measurement all outputs respond according to the features selected configured using SenixVIEW software. As shown in the table below some sensor series have a 6-wire cable that includes serial data and two SenixVIEW-selectable outputs. Other model series have a 9-wire cable with each output wired individually. Sensors are also available with only serial data communications and those have a 4-wire cable.

1. Serial Data (RS-232 or RS-485)

All Senix sensors include a serial data interface used primarily by SenixVIEW software but also available to user applications. Each sensor series has two serial data model options—RS-485 and RS-232. Both are industry standard electrical specifications with different characteristics. The RS-232 option is convenient for connecting to a single sensor over relatively short distances or with compatible equipment such as an older PC COM port. We otherwise recommend RS-485 because of the following advantages:

• • Higher noise immunity
  • Operates over longer cable lengths
  • Supports up to 32 addressable sensors connected to a single data bus (but still great with a single sensor)

Both serial data interfaces use the industry standard Modbus protocol, although that can be changed using SenixVIEW to a simple ASCII streaming output for simple connections to other equipment like displays. SenixVIEW software uses Modbus for sensor configuration and performance monitoring, and you don’t need to understand Modbus to use it.

The communication baud rate is adjustable from 9,600 (default) to 115,200 baud to accommodate user applications. Proprietary features are included to improve data collection speed in multi-sensor applications.

2. Analog Current (4-20 mA) and Voltage (0-10 VDC)

The analog outputs vary proportionally with the measured distance. Sensor models can have either two or three simultaneous analog outputs (see above table). 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. The current and voltage outputs have independently adjustable output scaling, operate concurrently and utilize the same (adjustable) distance endpoints.

Using SenixVIEW software, analog functions and responses can optimized with 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 in-situ adjustable using the “teach” push-button.

The figure above shows an analog 4-20 mA current loop output scaling. A target is shown detected at the midpoint of the current loop analog range, which yields a sensor output value of 12 mA. Six-wire sensors can have simultaneous 0-10 VDC and 4-20 mA outputs selected, or either can be changed to a switch.

3. Switches

Sensors can have 1 or 2 switch outputs that turn ON or OFF at distance setpoints to start and stop external actions or indicators. Switch parameters are fully adjustable using SenixVIEW.

Each switch has hysteresis control which means it can be turned ON at one distance and OFF at another. A single switch output can therefore perform a control function such as managing the liquid level in a tank by turning a pump or valve on or off at predetermined levels. Switches can also be set ON or OFF only when a target is within a specified distance window, allowing a single switch to set an alarm output for a high level, low level, or both.

Using SenixVIEW each switch can be set to “NPN” type (sinking) or “PNP” type (sourcing) for universal compatibility. A sinking switch turns “on” by connecting a powered device to ground, such as an external interposing relay, thus creating current flow. A sourcing switch connects connects the sensor’s power supply to an external device, i.e., “sourcing” current to a device to turn it ON. Switch functions and responses can be 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. Some switch features are also adjustable using the “teach” push-button.

ToughSonic switch outputs are solid state and designed to switch DC voltages. A DC powered conventional or solid state interposing relay must be added externally to switch AC or higher current DC loads.

For additional output information see the product manual or contact Senix Customer Service.