Enabling Temperature Compensation in an APG Ultrasonic Sensor

You can connect and configure an APG Ultrasonic sensor to your Wavelet. Typically, you need to compensate for temperature changes in the sensor. The APG sensor will self-calibrate for temperature changes during each data sample.

For more information about how temperature can affect an APG Ultrasonic Sensor, see  Application Challenge: Temperature Gradients in the APG Measurement Expert Blog.  


Ayyeka Part Number: SE00169

APG Part Number: MNU-IS-S6424-C35C



Add a channel to control temperature compensation setting

Add a stream to see the temperature compensation


To add a channel to control the temperature compensation setting:

  1. Log in to the Ayyeka the UI UI.
  2. In the left pane, click Devices.
  3. In the Site Tree pane, select the relevant site, and then select the relevant device that the sensor will be connected to. 
  4. In the right pane, click the Configuration tab.
  5. In the Configuration window, scroll down and click Advanced Device Configuration.
  6. In the configuration tree, click Serial to open its folder.
  7. In the Serial folder, click CHANNEL, and then select the next available channel that does not have a sensor assigned to it. An example might be Serial > CHANNEL > 1.
  8. In the channel folder, set the following parameters and values:
    • bus_baud – 9600
    • bus_parity – None
    • Interface_type – RS-485
    • active- AS_ON
    • sample_handler – SH_MODBUS_RTU
    • wake_time_ms – 13000
    • slave_addr- 1
    • read_addr- 419
    • read_type – MODBUS_READ_HOLDING_S16
    • sensor_power_source – Select either PS_EXT3_BOOSTor PS_EXT4_BOOST. If you are unsure, check which setting is used in another Wavelet that is connected to an APG sensor.

    • startup reset flag – 1

    • extra_params – 2,1,*

Important: Do not add any space between the values or the commas (,).


To add a stream to see the temperature compensation:

  1. Swipe the magnetic Wavelet Activator over the Ayyeka symbol on the face of your device.
  2. In the Ayyeka the UI UI, go to the device with the APG Ultrasonic Sensor.
  3. Click the Commands Wait about 10-15 minutes after swiping the magnetic Wavelet Activator until the Status column shows all the commands at 100% .
  4. Click the Configuration tab, and then scroll down to the Stream Management
  5. Click the Refresh icon . The new APG Ultrasonic sensor stream is listed in the Stream Management table.
  6. Click the plus sign icon + in the Stream column of the new stream.

a. Set the following parameters in the new stream:

New Stream Display Name: Temperature Compensation

Engineering Units: Unitless ()

b. Click Submit to define the new stream.

  7.  Click the refresh icon again, and then wait for a transmission to begin receiving values. The Raw Value and the Final Value of the ‘Temperature Compensation’ stream should be 1 (temperature compensation is enabled). A value of 0 means that temperature compensation is disable.