Editor’s note: This is the first part of our look at programming your ultrasonic sensor to ignore unwanted targets. You can find part 2, “Narrowing the Beam” here, and part 3, “Blanking Distance” here.
Maximum Distance
In ultrasonic level sensor applications, there may come a time when you need to program the sensor to ignore permanent fixtures in the bottom of a tank, such as submerged pumps or pipes. These fixtures could interfere with an accurate level measurement.
To ignore permanent fixtures such as found on the bottom of a tank, you will want to utilize the maximum distance feature.
The maximum distance is set from the sensor face to the point where the sensor will stop looking for target signals. The sensor will ignore targets detected beyond the maximum distance. Keep in mind that the level sensor will display the maximum distance value whenever the target is beyond that limit, or if the signal is ever lost (no targets detected).
To set up the maximum distance in the IRU series ultrasonic sensors, complete the following steps:
Step 1: Connect the RST-3001 programming module to the sensor and your computer and open the IRU software.
Step 2: After communication has been established, enter the desired maximum distance in the window marked “Max Distance”.
Step 3: Click on the “Send” tab. This will send the new parameter to the sensor.
The “Max Distance” setting essentially becomes the full scale range of the IRU sensor. Any potential targets beyond the maximum distance parameter will be ignored and will not interfere with having an accurate level measurement.
