Accurate moisture content measurement can help prevent spoiled grain in storage settings and help avoid discounts at the elevator if it’s sold too wet or dry. Moisture meters are valuable tools to keep track of that stored grain.
However, moisture meters will not provide accurate readings on corn coming from a high temperature dryer. The error will vary depending on the amount of moisture removed and the drying temperature, but the meter readings may be 2% lower than the true moisture in the bin.
In order to help get an accurate moisture reading grain handling experts recommend an initial sample be tested and then placed in a closed container for 12 hours. Then the sample should be checked again to determine the amount of error.
Moisture meter errors increase as corn moisture contents increase, so readings above 25% should only be considered estimates.
These meters are also affected by grain temperatures. If it does not automatically measure this temperature and adjust the value, then it must be done manually. Even if the meter does it automatically, it is recommended to cool a sample in a sealed container to room temperature before measuring the moisture content. This temperature reading can then be compared to the initial sample to verify that the adjustment is done accurately.
It is also important to remember moisture meters are not normally accurate when grain temperatures are below 40 degrees. Again to get an accurate reading the samples needs to be warmed to room temperatures before taking a measurement.
For questions on individual moisture meters, consult your owner’s manual or contact the point of sale for help. For further corn drying and storage information, view the Corn Drying and Storage Tips for 2011 publication by North Dakota State University.