EM2 & EM3 Moisture Retare Warnings and/or Fluctuating Moisture Readings

11 Nov 2024

Description

When using an EM2 or EM3 model moisture sensor in an H2 series GrainGage, Mirus sometimes gives a retare warning when harvesting plots. In addition, moisture readings fluctuate higher and lower than the known moisture readings (i.e. when compared to lab moisture meter).   

Fix

  1. Double check the steps outlined under article 14627 - "Inaccurate Moisture or NIR Constituent Data"
  2. Using "Diagnostics" within Mirus, check the following with sensor installed:
    • EM Voltage - should be around 1.5 - 2.0 Volts
    • EM Frequency - should be around 3.5 - 4.0 mHz
  3. Remove moisture sensor from GrainGage and check to ensure screws holding blade to the sensor housing are secure. Remove the two screws holding the blade to the sensor housing and clean under the blade with a small wire brush. Reassemble the blade and tighten mounting screws securely. Do not use loc-tite on screws for this may cause some electrical isolation between blade and sensor housing.  
  4. Reinstall moisture sensor in GrainGage and repeat step #2. If voltage and frequency readings are different than before, run a sample through system to check calibrations. Recalibrate if nessesary.    

If the problem persists, contact the HarvestMaster Field Service Engineers. For contact information, see Contact a HarvestMaster Field Service Engineer.