Load Measurement Unit

1.​ Applicable products

  • Series 1780 Thrust Stand and Dynamometer:

-Single-motor: 25 kgf - 100 A
-Single-motor: 40 kgf - 150 A
-Single-motor: 75 kgf - 500 A
-Basic Coaxial: 25 kgf - 100 A
-Basic Coaxial: 40 kgf - 150 A
-Ultimate Coaxial: 25 kgf - 100 A
-Ultimate Coaxial: 40 kgf - 150 A

2.​ What describes your problem?

Please find within the following table which describes your problem. Once selected, mark down the troubleshooting points to follow.

Table scope
3.
 Problem specific troubleshooting

3.1​ I see that the load cell installed in the structure is broken.

  • When you see one or more load cells on the LMU are damaged, please immediately stop using the LMU for any other tests.
  • If you can see an obvious crack or the load cell was broken into fragments, take a picture of the broken section in a close view.

  • Subject: LMU load cell damage
  • Your shipping address
  • Your purchase invoice number or shipment record
  • Please do NOT attempt to repair the LMU by yourself.
  • You may pack the LMU back to the protective casing.
  • A load cell damage always requires a back-to-factory repair and recalibration, we will send you further instruction about the RMA and return process.

​3.2​ I had a safety cut-off during the test and the software said “Load cell overloaded”.

  • Stop all tests and disconnect the stand from the power source.
  • As long as the voltage drops under 15 V, approach the stand and check physically load cells on the LMU if they are damaged. If so, see section 3.1 for the RMA and repair.
  • Keep the mainboard connected to the PC, and open the RCbenchmark GUI.
  • Go to SETUP tab and check the box “Activate debug mode”

  • Once selected, you shall be able to see the DEBUG tab on the left main menu.
  • Now connect the mainboard with the thrust stand.
  • At the bottom-left of the GUI, you shall be able to see the real-time value of all the measurements including the debug values:

  • You can find six channels load cell output under the debug values. Copy the value Load Cell 0 to Load cell 6.
  • If any of the values exceeds 0.3, the load cell has potentially been damaged. Send these values to support@rcbenchmark.com and please include the following info:
  • Subject: S1780 LMU load cell overloading
  • The six channels Load Cell raw value in text or in screenshot
  • Your purchase invoice number or shipment record
  • If any of the values does not exceed 0.3, and then you will need to run further diagnosis with a few extra steps.
  • Dismount the motor and the propeller from the LMU.
  • Remove the LMU from the stand and place it horizontally, without any load. We recommend placing it back on the protective casing as such:

  • And then connect again to the mainboard and capture these six load cell raw values when the LMU stays still and stable on the stand-off.
  • Send your case to support@rcbenchmark.com with the following info:
  • Subject: S1780 LMU load cell overloading
  • The six channels Load Cell raw value in text or in screenshot when on the stand
  • The six channels Load Cell raw value in text or in screenshot when horizontal
  • If one or more load cells have been damaged, you will then need to ship the unit back to RCbenchmark for a repair and recalibration.

3.3​ I had a safety cut-off before any tests and the software did not allow any manual control.

  • Keep your Series 1780 connected to the PC and go to the Manual Control tab on the left.
  • Under the ESC throttle bar, you shall be able to see a warning in red:

  • Please make a screenshot of this alert. Take note that you may have a different alert than the picture shown above.
  • Physically disconnect the stand from the power source.
  • As long as the voltage drops under 15 V, approach the stand and check physically load cells on the LMU if they are damaged. If so, see section 3.1 for the RMA and repair.
  • Keep the mainboard connected to the PC, and open the RCbenchmark GUI.
  • Go to SETUP tab and check the box “Activate debug mode”

  • Once selected, you shall be able to see the DEBUG tab on the left main menu.
  • Now connect the mainboard with the thrust stand.
  • At the bottom-left of the GUI, you shall be able to see the real-time value of all the measurements including the debug values:

  • You can find six channels load cell output under the debug values.
  • Dismount the motor and the propeller from the LMU.
  • Remove the LMU from the stand and place it horizontally, without any load. We recommend placing it back on the protective casing as such:

  • And then connect again to the mainboard and capture these six load cell raw values when the LMU stays still and stable on the stand-off.
  • Send your case to support@rcbenchmark.com with the following info:
  • Subject: S1780 LMU load cell overloading
  • The screenshot of the warning message
  • The six channels Load Cell raw value in text or in screenshot when on the stand
  • The six channels Load Cell raw value in text or in screenshot when horizontal
  • If one or more load cells have been damaged, you will then need to ship the unit back to RCbenchmark for a repair and recalibration.

3.4​ I heard the mainboard buzzing.

Generally speaking, mainboard buzzing is a sign that the LMU was overloaded from the past operation.

  • Keep your Series 1780 connected to the PC and go to the Manual Control tab on the left.
  • Under the ESC throttle bar and check if you see any warning message.

  • If there is an alert, please make a screenshot and pass to the next step. If there is no alert, simply pass to the next step as well.
  • Physically disconnect the stand from the power source.
  • As long as the voltage drops under 15 V, approach the stand and check physically load cells on the LMU if they are damaged. If so, see section 3.1 for the RMA and repair.
  • Keep the mainboard connected to the PC, and open the RCbenchmark GUI.
  • Go to SETUP tab and check the box “Activate debug mode”

  • Once selected, you shall be able to see the DEBUG tab on the left main menu.
  • Now connect the mainboard with the thrust stand.
  • At the bottom-left of the GUI, you shall be able to see the real-time value of all the measurements including the debug values:

  • You can find six channels load cell output under the debug values. Copy the value Load Cell 0 to Load cell 6.
  • If any of the values exceeds 0.3, the load cell has potentially been damaged. Send these values to support@rcbenchmark.com and please include the following info:
  • Subject: S1780 LMU load cell overloading
  • The screenshot of the warning message if you see any
  • The six channels Load Cell raw value in text or in screenshot
  • Your purchase invoice number or shipment record
  • If any of the values does not exceed 0.3, and then you will need to run further diagnosis with a few extra steps.
  • Dismount the motor and the propeller from the LMU.
  • Remove the LMU from the stand and place it horizontally, without any load. We recommend placing it back on the protective casing as such:

  • And then connect again to the mainboard and capture these six load cell raw values when the LMU stays still and stable on the stand-off.
  • Send your case to support@rcbenchmark.com with the following info:
  • Subject: S1780 LMU load cell overloading
  • The screenshot of the warning message if you see any
  • The six channels Load Cell raw value in text or in screenshot when on the stand
  • The six channels Load Cell raw value in text or in screenshot when horizontal
  • If one or more load cells have been overloaded, you will then need to ship the unit back to RCbenchmark for a repair and recalibration.

4​. Problems persist?

In general, the six channels load cell raw values are the best parameters to determine if the LMU has been overloaded, impacted or damaged.

We support all issues related to the measurement tools itself, and we can provide limited support regarding your test setup and power-train selection. If you need extended support for your specific tests, manufacturing facility or UAV, contact us at sales@rcbenchmark.com. We offer extended support contracts including phone and video conference at affordable rates.

To obtain a solution to your problem faster, please indicate which troubleshooting steps you have already done. Also, include the debug log from the software. If relevant, please also include screenshot or pictures of the issue.

​4.1​ Cross-reference to other types of problem

  • SITMDG: a load cell failure will lead to incorrect measurements

​4.2​ Cross-reference from other types of problem

  • SITVIB: vibration may damage the load cell
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