Getting started with tank monitoring

This article will guide you through the installation, setup, and operation of your tank monitor to ensure accurate and reliable performance from day one.

Your tank monitor is designed to provide real-time insights into fuel levels and system status, helping you manage your assets efficiently and reduce manual checks. The installation process is straightforward, and this article will walk you through each step — from preparing the monitor to viewing and calibrating your data.

About this article

• Preparing and Installing the Tank Monitor:
  Learn how to connect the level sensor, activate the batteries, close the case, and mount the device properly.

• Viewing and Calibrating Data:
  Step-by-step instructions for accessing your Tank Dashboard, editing asset information, and entering calibration data for accurate readings.

• Troubleshooting:
  Solutions for common issues such as missing GPS data, incorrect fuel levels, or connection problems.

• Maintenance and Battery Replacement:
  Guidance for keeping your device in optimal working condition.

If you’re using a different tank monitor model, refer to the section Different Tank Monitor at the end of this article for specific instructions.

By following this guide, you’ll be able to set up your system quickly and ensure your tank monitor delivers accurate and consistent data.

Preparing the tank monitor for installation

Your tank monitoring system arrives fully assembled and ready for setup. The monitoring module comes with the SIM card and batteries pre-installed, so you can begin the installation process right away.

Please note that the level sensor shown in the packaging may vary depending on the specific model you ordered. This sensor must be connected to the monitoring module before use. Follow the connection steps carefully as outlined in the installation instructions provided with your unit.

Before proceeding, we recommend:

• Verifying that all components are included and undamaged.

• Reviewing the installation diagram that matches your sensor type.

• Ensuring you have the necessary tools for mounting and connecting the sensor.

Connecting the level sensor

The correct connection of the level sensor is essential for accurate measurements.
Depending on your sensor model, the type of fluid in the tank, and the software configuration, the connection procedure may vary.

Follow the installation guide specific to your sensor type to ensure proper setup. Make sure all connectors are secure and that cables are not bent or damaged during installation.

Wiring instructions for a 4-20mA sensor using BD 18.605G

• White wire (Voltage) → I/O2 +VBOOST OUT

• Brown wire (4-20mA) → I/O9 4-20mA

Important!

Each measurement module must be equipped with the appropriate software configuration for its intended application. For example:

• A module configured for a fuel sensor uses a different software setup than one configured for an AdBlue sensor.

• Using the wrong configuration can result in inaccurate readings or communication errors.

If you are unsure about your configuration, or if you would like to use the system for combination measurements (e.g., multiple sensor types), please contact Calculus Support before proceeding. Our team will be happy to assist you in selecting or updating the correct configuration.

Activating the batteries

Before using your monitoring module, you’ll need to remove the battery strip to activate the batteries.
Once the batteries are activated and the module is inserted, the LED indicator located next to the GPS antenna will flash briefly. This confirms that the module has powered on correctly.

If the LED does not flash after activating the batteries:

• Remove the batteries from the module.

• Leave them out for at least five minutes to allow any residual charge to dissipate.

• Insert the batteries, ensuring they are placed correctly according to the polarity markings.

• Check again for the LED flash to confirm a successful activation.

If the LED still does not blink after repeating these steps, please contact Calculus Support for further assistance.

Closing the case

Once the batteries are activated and the module is ready, you can close the gateway housing.

1. Position the lid correctly on top of the gateway.

2. Gently press it down until it fits snugly. The foam layer inside the lid should press lightly against the batteries — this keeps them securely in place, even when the device is moved or turned over.

3. Tighten the eight screws evenly, using a cross pattern (for example, tighten opposite corners in sequence) to ensure a uniform seal.

   Note: The screws may feel stiff during the first assembly. This is normal.

Important – Check Lid Orientation

Before tightening the screws, verify that the lid is correctly positioned.

The foam insert must be on the inside, directly above the batteries.

If the lid is attached upside down or misaligned, it can damage the gateway or prevent it from sealing properly.

Installing the tank monitor

Installation

The gateway can be securely mounted to the object you wish to monitor using screws, bolts, cable ties, or industrial adhesives, depending on your setup and the surface type.
Before selecting a mounting location, please take the following factors into consideration:

1. Choose a mounting point that minimizes the risk of accidental mechanical damage.
   Many customers prefer to install the module inside the tank for added protection. However, please note that the metal housing of some tanks can interfere with GPS or data transmission.

2. Optimize reception and ventilation.
   Mount the gateway in a location with strong GPS and mobile network reception. Ensure there is adequate ventilation and free space around the module to prevent overheating or interference.

3. Use the correct sensor for each fluid.
   Always use a fuel sensor exclusively for fuel applications. Do not use it for other liquids such as AdBlue, as this may cause incorrect readings or sensor damage. Dedicated sensor types are available for AdBlue and other fluids—contact Calculus Support for more information.

4. Installing the hydrostatic pressure sensor.
   Allow the sensor to hang freely through a tank opening so that it reaches just above the tank bottom. To prevent cable strain or breakage, it is best to secure the sensor cable using a riser pipe or similar support structure.

5. Activation and configuration.
   Once powered on, the module will automatically connect to the online platform and update itself with the pre-programmed configuration assigned to your device.

   This process may take a few minutes, depending on network strength.

Upon activation, the module will connect to the online platform and update itself with a pre-programmed configuration.

Important – Reception and Battery Life

When operating the gateway in battery-powered mode, optimal reception is crucial.

Poor signal quality can lead to reduced performance and shorter battery life, as the module will attempt repeated transmissions.

Always verify that the chosen mounting position provides consistent signal strength before finalizing installation.

Viewing data

Each tank monitor has a unique serial number, which you can find on the label printed on the module housing.

You can view the data of you tank monitor on the Calculus Portal.
Navigate to Dashboards.
Enter the serial number of your tank monitor in the search bar.
Select your device from the list to open its dashboard.

Within the dashboard, you can quickly check whether your device is online or offline by viewing the activity indicator:

🟢 Green – The device is online and actively sending data.

⚪ Gray or 🔴 Red – The device is currently offline or not transmitting data.

If your device shows as offline, it may be due to temporary network coverage issues or the activation process still completing.

Hint!

After removing the battery strip and activating the device, it may take a few minutes before the first data appears on the platform.

This delay is normal while the module connects to the network and uploads its initial readings.

Calibrating the tank monitor

To ensure accurate level measurements, your tank monitor must be calibrated once the tank is completely filled. Calibration allows the system to correctly interpret the sensor data and convert it into real-world volume readings.
Follow the steps below to perform the calibration:

Step 1: Open the Tank Dashboard

1. Navigate to the Dashboard of the tank you want to calibrate.

2. Scroll down until you find the widget titled “Max Raw Sensor Data in Period.”

   • This widget shows the maximum raw sensor value recorded for the selected period.

   • Make sure the tank is completely full before taking this value.

Step 2: Access the Edit Asset page

1. At the top of the dashboard, you’ll see the tank name followed by an arrow icon.

2. Click the arrow to open the Edit Asset page.

3. On this page, select the Metadata tab.

Step 3: Enter calibration data

In the Metadata tab, you’ll see several variable fields. For a fuel tank, the two most important ones are:

• TankLiter: The total capacity of your tank in liters.

  • Example: If your tank holds 300 liters, enter 300.

• Tank100pct: The sensor’s raw value when the tank is completely full.

  • Enter the value shown in the Max Raw Sensor Data in Period widget from the dashboard.

These two values allow the system to calculate the fill level as a percentage and display accurate volume readings.

Tip

It’s best to perform calibration immediately after refilling the tank completely, ensuring that the Max Raw Sensor Data value truly represents a 100% full level.

After saving your entries, the system will automatically update the tank’s level calculations based on your input.

Troubleshoot

Changing the batteries

All new modules come preinstalled with fresh batteries. If a module goes offline shortly after activation, depleted batteries may be the cause. Battery life and performance can vary depending on several factors, including:

• Natural voltage degradation over time.

• Environmental conditions, such as extreme heat or cold.

• Device transmission frequency (how often the device sends data).

• Network signal strength, for both data and GPS connections.

The type of battery used is critical for proper operation. When a 4–20 mA sensor is connected to the gateway, you must use Lithium Thionyl Chloride (LTC) batteries, bot all LTC batteries are the same.

• Spiral-type LTC batteries are preferred, as they can deliver the high peak current required for transmission.

• Bobbin-type LTC batteries may not provide enough peak current, which can cause device instability or communication issues.

When replacing the batteries and opening the device case:

1. Carefully open the case and remove the old batteries.

2. Insert the new LTC batteries, ensuring correct polarity.

3. Before closing the case, check the silicone seal for any signs of wear or damage.

   The seal must be intact to maintain the device’s waterproofing and environmental protection.

4. Close the case securely.

No GPS data

The module automatically attempts to obtain a GPS fix every 12 hours. In some cases, the module may fail to get a fix — most often when it is installed under metal or iron covers, or in other locations where satellite signals are obstructed.

• Optimal GPS Conditions.
  For the best GPS performance, the module should have a clear view of the sky. Try to install it in a position where it can “see” open air and is not blocked by metal structures, tanks, or thick concrete.

• Forcing a New GPS Fix.
  If no GPS data is being received, you can prompt the module to obtain a new fix by performing a manual reset by removing the batteries for at least 5 minutes. Once power is restored, the module will automatically attempt to acquire a new GPS fix.

GPS reception quality depends on several conditions:

• Geographical location (urban areas with tall buildings can interfere with signal).

• Installation position and orientation of the device on the asset.

• Whether the asset is located in open air or enclosed spaces.

If the module still fails to come online after resetting, test the device in a different location where you are confident there is strong GPS and network reception. Ensure it is placed outside of any fuel tank housing or metal enclosure.

No sensor data

If no sensor data is being received, it’s usually due to a connection issue. Steps to check:

1. Verify the sensor connection.

   • Make sure the sensor is connected exactly as described in the installation manual.

   • Inspect all connectors, terminals, and cables for proper fit and alignment.

2. Check for loose or damaged contacts.

   • A loose or corroded connection may prevent data transmission.

   • Re-seat the connector if necessary, ensuring it clicks or fits firmly in place.

3. Confirm sensor type compatibility.

   • Ensure that the connected sensor type is supported by the module or gateway.

If the problem persists after confirming all connections, try testing the module with another sensor and vice-versa (if available) to determine whether the issue is with the sensor or the module.

No fuel level data is received, but other data is

If the module is transmitting other data correctly but no fuel level information appears, the issue may be related to how the level sensor is calibrated and linked.

The fuel level sensor relies on metadata that belongs to the specific asset it is linked to. When multiple assets are connected to the same gateway, the system encounters duplicate metadata. This duplication causes confusion in the portal, preventing it from determining which metadata set to use — and as a result, the fuel level is not calculated.

Caution!

Always maintain a one-to-one connection between a gateway and an asset.

Linking multiple assets to a single gateway will result in missing or incorrect data, including fuel level readings.

Fuel tank capacity does not correspond to actual tank capacity

If the displayed fuel tank capacity differs from the actual capacity, the issue is most likely related to sensor calibration.
Verify the sensor calibration by checking the metadata. Recalibrate the sensor if necessary.

The tank has just been filled and the data online does not match

If the displayed data does not immediately match the actual tank level after filling, this is normal behavior and typically resolves on its own.
When a tank is filled, the process can create temporary internal air pressure. This pressure may cause the sensor to report slightly inaccurate readings right after refueling. The system automatically corrects the reading during the next data reading.

Tip!

If the readings do not normalize after several measurement cycles, check if the air tube isn’t blocked or bent.

Calibrating the tank when it isn’t fully filled

You can calibrate your tank even if it isn’t completely full.

By entering a few key values, you can create an estimated calibration, which can later be fine-tuned when the tank is filled to its maximum capacity.

Tip!

After performing an estimated calibration, we recommend recalibrating the tank again when it is completely filled to ensure the most accurate measurements.

To perform an estimated calibration, gather the following information:

1. Current amount of fuel in the tank (litres)

2. Maximum tank capacity (litres)

3. Latest raw sensor data

   • You can find this value at the bottom of your Tank Dashboard. It represents the sensor’s latest uncalibrated measurement.

Use these values to fill in the calibration table below and generate an estimated calibration curve.

Different tank monitor

If your tank monitor looks different from the one shown below, you may be using an older model.

Check the wiring diagram to find the correct instructions for the following models:

• Digital Matter Hawk

• Digital Matter Falcon

• Digital Matter Eagle

Each model may have slightly different installation and configuration procedures, so make sure you’re referencing the correct article.

Hint!

If you’re unsure which type of gateway you have, remove the lid and look for the white label on the circuit board.
The label lists the model name, which will help you identify the correct article.