Tank Levels Calibration. Maretron DSM250-01

To program the tank capacity, use the Scroll Up ( ) or Scroll Down ( ) keys to move the highlighted cursor over the “Tank Capacity:” menu item. Then, press the Enter key ( ) to move the highlight over the numerical tank capacity value. Use the “Increase” and “Decrease” keys to change the value to the desired tank capacity value, and finally, press the Enter key ( ) to confirm your selection and store the value within the TLA100.

Figure 184 – Configuring the Tank Capacity

After you have pressed the Enter key ( ), a confirmation screen will appear that warns you that the fluid remaining measurement will change as a result of this change. Press the Accept key to accept the change and store the new tank capacity value within the TLA100, or Press the Cancel Key ( ) to cancel the change and leave the old tank capacity programmed into the TLA100.

Figure 185 – Tank Capacity Change Confirmation Screen

6.23.4 Tank Levels Calibration

In order for the TLA100 to indicate an accurate tank level, it must know how the resistance of the resistive tank level sender corresponds to the level of fluid in the tank. There are three methods of calibrating the tank level sender:

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• Custom Calibration – use for non-rectangular tanks or non-standard sensors (also, most accurate in any case, but requires more effort)

• Set to American Standard (240-33 ohm) – use for rectangular tanks using a tank level sender with the standard American resistance range (240 ohms at full, 33 ohms at empty).

• Set to European Standard (0-180 ohm) – use for rectangular tanks using a tank level sender with the standard European resistance range (0 ohms at full, 180 ohms at empty).

6.23.4.1 Custom Calibration

The Custom Calibration setting will provide the most accurate tank level readings under any circumstances, but it requires that you go through a process in which you gradually fill the tank, stopping periodically to input the current fluid level. The TLA100 will measure the sender resistance at each point and create a custom calibration map which relates the resistance of the sender with the

fluid levels. Figure 186 below shows a screenshot of the DSM250 with the Custom Calibration option

highlighted. Custom calibration is necessary for non-rectangular tanks and for non-standard values of resistances for tank level senders. To perform custom calibration of the tank level sender, use the

Scroll Up ( ) or Scroll Down ( ) keys to move the highlighted cursor over the “Custom

Calibration…” menu item. Then, press the Enter key ( ) to confirm your selection and begin the calibration process.

Figure 186 – Performing Custom Calibration of the Tank Level Adapter

The first step in custom calibration of the tank level sender is to provide an estimated capacity of the tank. This estimated capacity must be within +/- 25% of the actual capacity. To set the estimated tank capacity, use the arrow keys to adjust the displayed value until the desired value is shown. Then, press the Accept key to confirm your selection and continue with the calibration process. If you desire to stop the calibration process, pressing the Back Key ( ) will end the process and return you to the Tank Levels Calibration menu.

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Figure 187 – Tank Levels Calibration Capacity Estimation

The next step in the calibration process is to fill the tank and indicate the volume of fluid in the tank at various points while filling the tank. This process should be started with an empty tank. You only need to indicate two calibration points for a rectangular tank, and can use up to 16 calibration points for a

tank with a more complex shape. Figure 188 shows a screenshot of the first calibration step. Enter

the first calibration point with an empty tank (0.0 Gallons/liters) by pressing the Accept key. The

“Current Point” highlight will advance to the next point.

Figure 188 – Empty Level Calibration

Each time you press Accept during this process and after the Current Point highlight advances, put more fluid into the tank, and note the total volume of fluid pumped into the tank at this point. Use the

Increase

and Decrease keys to set the current tank level to the appropriate value, and then press the

Accept

key to store the current calibration point and advance to the next calibration point. Figure 189

shows a screenshot of these intermediate calibration points.

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Figure 189 – Intermediate Level Calibration

Once the tank is completely full, instead of pressing the Accept key to store the current calibration point, press the Complete key. This will complete the calibration process and will also adjust the tank

capacity to the currently indicated level. Figure 190 below shows the calibration screen at the last

point with the full tank level (and thus the tank capacity) set to 101 gallons.

Figure 190 – Full Level Calibration

After you press accept, a confirmation screen will appear showing completion of the calibration process and the new tank capacity value. A screenshot of this calibration screen is shown below in

Figure 191.

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Figure 191 – Custom Tank Level Calibration Confirmation Screen

6.23.4.2 American Standard Sender Calibration

If you have a rectangular tank, and a sender with the standard American resistance range (240 ohms full, 33 ohms empty), and you know the capacity of the tank, you can easily calibrate the sender by

using the “Set to American Standard (240-33 ohm)” menu item. Figure 192 below shows this option

highlighted. Use the Scroll Up ( ) or Scroll Down ( ) keys to move the highlight over this menu item, and then press the Enter key ( ) to write the calibration values within the TLA100 and complete the calibration process.

Figure 192 – American Standard Sender Calibration

6.23.4.3 European Standard Sender Calibration

If you have a rectangular tank, and a sender with the standard European resistance range (0 ohms full, 180 ohms empty), and you know the capacity of the tank, you can easily calibrate the sender by

using the “Set to European Standard (0-180 ohm)” menu item. Figure 193 below shows this option

highlighted. Use the Scroll Up ( ) or Scroll Down ( ) keys to move the highlight over this menu item, and then press the Enter key ( ) to store the calibration values within the TLA100 and complete the calibration process.

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