Overview

Vibrating wire dataloggers, such as Strands, Geokon Geonets or Dataloggers, or API-connected VW nodes, must be configured on the iTwin IoT application in order to begin collecting data and for certain calculated metrics to be accessible on the iTwin IoT platform. This article will review how to configure logger channels and provide an overview of the information inputs required to configure the VW sensor for calculated data metrics.

Configuring VW Channels on Devices

Please consult the article within this Wiki regarding your specific logger or API connection for instructions about adding that device. After the logging device has been added, follow the steps outlined below. In the example below, a Loadsensing Datalogger is being configured. The same workflow applies to all device channel configuration. Contact the Customer Success team if you have any questions regarding your specific device.

1. Navigate to the Connectivity Module. 

2. Click on the Datalogger Device.

3. Navigate to the "Edit Configuration" page of the device by clicking on the name in the column on the left of the page.

4. Click the blue "Edit Configuration" button below the Channel Information portion of the page. The pop-up window illustrated below will open, allowing the configuration of logger channels. The number of channels available for programming will be read from the device and automatically populated within this window, typically varying between 1-32 channels depending on the device. The example below illustrates a two-channel logger.

5. By default, channels are turned off, thus not reading the device channel or populating a sensor this channel. The input configuration allows the user to turn the channel on by selecting "Vibrating Wire". Once "Vibrating Wire" is selected, the "Category" option becomes available for configuration.

6. The "Category" dropdown allows the user to select the sensor type installed on that channel (ie piezometer, strain gauge, pressure cell). Once a Category is selected, the "Sensor" dropdown will become available.

7. The "Sensor" dropdown allows the user to select the specific sensor manufacturer and/or model. This selection may dictate the calibration factor inputs explained in the following section. The feature is designed to match the manufacturer's calibration sheet information with the application's sensor input configuration.

8. Once all configurations have been made, click "Apply" in the pop-out window. The pop-out window will close, bringing the user back to the "Edit Configuration" page. Click "Apply" once again in the "Edit Configuration" page to save the configured channel settings.

Once back on the main page of the Connectivity Module, the newly configured VW channels will be displayed as sensors below the logger device, as illustrated below.

Configuring VW Sensors

In order for iTwin IoT software to take the temperature and frequency raw metrics being supplied by the VW sensor and calculate engineering metrics, the VW sensor needs to be configured in the app. 

1. To configure the VW sensor, click on the sensor from the Connectivity Module.

2. Navigate from the Sensor Details page, clicking on the "Edit Configuration" button on the left side of the window.

3. The Calibration Factors inputs will vary depending on the sensor type and manufacturer. If using a Geokon vibrating wire, the user can input the Serial Number of the sensor in the input on the right side of the page and click the blue "Load by Serial" button. If this function does not work, or if the VW sensor is made by another manufacturer, the Calibration Factors can be found on the Calibration Record sheet provided by the manufacturer.

4. The Zero Value is the frequency, temperature, and pressure reading typically taken on-site prior to installation of the Vibrating Wire sensor. Once the "Edit Configuration" button is selected, a pop-out window will open allowing the user to input the required values (see below). The zero values can also be recorded with the logging device prior to installation, and "Zero from date" can be selected. Click "Apply" at the bottom of the window once the zero values have been input.

5. The Reference Date that you input will dictate how any Delta (Δ) metrics are calculated. The selected date and associated value (R1) will be the value from which other readings (R2) are compared (ΔR=R2-R1).

6. The Barometer Reference Sensor allows the user to select a pressure sensor on the asset in order to correct for barometric pressure deviation for calculated data of certain VW sensors. Clicking the "Edit Configuration" button will open up a sensor selection window where the user can select the appropriate pressure sensor from a dropdown list. Clicking "Apply" will save this change. 

Note: The Sampling Intervals of the VW sensor and the reference pressure sensor must match, or any calculated metrics utilizing a pressure correction will not be populated.

7. Any remaining configuration options will vary depending on the type of VW sensor. Hovering over the  icon next to the input can provide the user with insight about the required input. For any additional questions, reach out to Bentley's iTwin IoT Customer Success team here.

8. A thermistor override can be applied to the VW sensor in the event that the thermistor on the VW sensor has failed or is damaged and reporting inaccurate information. This allows for the continued collection of data for a sensor. Inputting a temperature value into the override will apply that value over any signal received from the VW sensor, and this value will be used for calculating metric data.

9. Click "Apply" to save all configuration settings.