Custom Sensors

Icon for launching "Custom Sensors"

When configuring devices, you will notice that every channel requires information about the sensor used to log data. A sensor is a description of how a physical quantity is transduced into an electrical signal (resistance or voltage). The AiM device reads and logs this electrical signal.

AiM provides a comprehensive set of sensors, but if they do not fit your needs, you can define your own: these are called custom sensors.

Note

Webinar Icon AiM Tech Tips short video, presented by Bryc Talley, named “Custom Fuel Level Sensors.” Click here to watch the August 26th, 2024 video.

The Custom Sensors Manager is a database window, vertically divided into two parts:

  • Right (List): Shows all custom sensors by default, including key details and buttons for main operations.

  • Left (Filtering): Allows filtering to display a subset of sensors. Options include: All Custom Sensors, Sensor Types, and Manual Collections.

All Custom Sensors

Select this item in the left column to view the full list of custom sensors you have created or imported.

At first use, this list will be empty. Click New to create a custom sensor from scratch, or Import to load one from a drive.

Custom Sensors of Specific Physical Quantities

If you create or import custom sensors for different physical quantities, the left column will display one row for each quantity.

Selecting a quantity filters the list to show only the custom sensors associated with it.

Custom Sensors in Manual Collections

You can manually group custom sensors into collections. After creating a collection, selecting it displays only the sensors you placed in it.

List of Custom Sensors

The toolbar above the list of custom sensors allows the following operations:

  • New / Delete - Create or remove a custom sensor.

  • Import / Export - Import a custom sensor from an external drive, or export one to a drive.

  • AiM Support - Send a custom sensor to AiM Support, along with a request for explanation.

Creating a Custom Sensor

A custom sensor converts the input values read by a channel into the physical quantity you want to record. Before starting, obtain the sensor supplier’s table or curve, including the input type, physical quantity and units. A name alone does not define the conversion.

Custom Sensor Example: a Pressure Table

Suppose a supplier’s table specifies the following conversion. These values are illustrative; they are not the specification of a particular sensor.

Example supplier table

Input (mV)

Pressure (bar)

500

0

4500

10

  1. Open Custom Sensors and click New Sensor. Enter a unique name, for example DemoPressure, in the Sensor Name dialog and confirm. The sensor editor opens in a tab.

  2. Set Measure Type to Pressure. Set Calibration Type to None for this example: the table supplies the conversion directly.

  3. Under Input Type, select mV. The other input type is Ohm, for a table expressed as resistance. Use the type specified by the supplier.

  4. Click the unit heading of the table’s right column and select bar. Check the column headings before entering the numbers: the left column is in millivolts, so enter 500 for 0.5 V and 4500 for 4.5 V.

  5. Click each table cell to enter the two pairs above. Use the row + and - controls to add or remove points when your supplier’s table has a different number of rows. Tab moves between the input and output cells.

  6. Click Compute Curve. Check the plotted points and the curve against the supplied data. In this two-point example, the graph joins 500 mV / 0 bar and 4500 mV / 10 bar with a straight line.

  7. Click Save. A successful creation displays Sensor created and saved, and the sensor becomes available in the manager and in configuration sensor selection lists.

For a nonlinear supplier table, enter the supplied points rather than replacing the table with the two endpoints of this example. After changing the table, click Compute Curve again and review the result before saving.

Using and Updating a Custom Sensor

  1. Open a configuration for the intended device and its Channels tab.

  2. Open the channel that will use the sensor. Choose a function with the same physical quantity as the sensor, then select the saved custom sensor by name. For the example above, use a pressure function and DemoPressure. The available functions and sensors depend on the device and channel.

  3. Confirm the channel settings, then follow Saving and Transmitting a Configuration.

Saving the sensor adds its definition to RS3. The device uses it after the configuration containing that sensor has been transmitted.

To edit an existing custom sensor, open it from the manager. Save updates that sensor; Save As creates a separately named sensor. Configurations shows the configurations that use it. When you save changes to an existing sensor, RS3 opens the procedure for updating configurations that refer to the previous definition. Review those configurations and transmit the required updates to the devices.

Custom Sensor Problems

  • Save is unavailable or the curve shows an error: choose a measure type and enter at least two points with different input and output values. Click Compute Curve and read the error displayed in the graph area.

  • The name is rejected: a sensor name must not be empty or already used. Choose another name, or open the existing sensor to update it.

  • The values have the wrong scale: check Input Type and both table headings. In particular, the voltage column expects mV. Select the output unit before entering values from a supplier’s table.

  • The sensor is absent from a channel’s list: check that the channel’s function has the sensor’s physical quantity and that the intended device and channel support that selection.