To reduce the margin of error, yield monitors should be calibrated at three operating capacity levels . . . A point of clarification, 'low flow' means more than a trickle. The sensors in yield monitors have limits. In fact, many yield monitors have a cut off that does not allow extremely low flow rates to be measured. Another common error made when combining crops is lifting the head too late or lowering the head too early at the beginning or end of the pass.
Many monitors use the header switch to start and stop measuring the distance traveled.
Recalibrate every time conditions change. It helps to understand how the monitors work. The sensors merely sense and record the pressure of grain hitting the plate. Thus, wet grain, which is heavier than dry grain, will increase the pressure against the plate. This can cause the monitor to provide misleading information.