Harvest - Finding and Entering Load Cell Ratings (Sensitivity / Rated Capacity)
Finding Load Cell Ratings
All load cells installed on the grain cart MUST have identical ratios of sensitivity to capacity (sensitivity/capacity). This is true if all load cells are of the same model and should be checked otherwise.
Using the calibration number from an existing indicator:
Find and note the calibration number of your existing indicator as the
Rated Capacity (lb), and use 0.40 mV/V as the
Sensitivity. Please consult the existing indicator's user manual for help retrieving the calibration number. Go to Storing Load Cell Ratings.
In all other cases:
Read and note the
Sensitivity (Rated Output) and
Rated Capacity (Rated Load) from any one load cell on the grain cart. Multiply the
Rated Capacity by the TOTAL number of load cells on the grain cart. If specifications are unavailable, a good starting point is a
Sensitivity of 0.40 mV/V and a
Rated Capacity of 8000 lbs multiplied by the TOTAL number of load cells on the grain cart.
Storing Load Cell Ratings
- Ensure the Libra Cart device and Libra Harvest app are paired and connected.
- Ensure units (lb, kg) are set to those of the Rated Capacity found previously.
- Select the Device tab and enter the Sensitivity and Rated Capacity noted previously by tapping on the Sensitivity or Capacity number in Blue.
- Tap Next and Save.
- Tap the blue Calibration number. Enter the Calibration Factor as 1.0 if it's not set at 1.0 already.
- Tap Next and Save.
- Select the Device tab, ensure the cart is empty, tap Zero Scale and confirm Zero.
- Select the Display tab and tap Tare.
- Apply a known weight (perhaps your body weight) to one of the cart's load cells, recording the displayed weight. Repeat with each remaining load cell. If the load cells agree and are roughly correct, you can now calibrate. If the load cells agree but are roughly half of that expected, double the Rated Capacity entered previously. If weights do not agree, check wiring and load cell orientation.