A yield monitor needs two distinct pieces of hardware to function.
- Impact plate and/ or a sensing mechanism
- Documentation – Display and GPS to record data
These two key components work together to calculate your yield. This is achieved from the impact plate being hit with grain which in turn allows for it to determine the amount of grain that is flowing into the machine. Example video below shows how the material is thrown against the impact plate.
There are two types of yield calibrations that can be utilized
- Single-point Calibration
- Multi-point Calibration
Difference Between Calibrations
- In the graph above it depicts the difference between single-point calibrations and multi-point calibrations.
- The green, blue, and yellow line are various single-point calibrations and the red line is a multi-point calibration.
- When looking at the graph we drove at various speed and flow rates to get the 5 red triangles.
- We can then see that when we use a single-point calibration, the calibration factor becomes inaccurate once we no longer are operating at the same speed and flow rate. This will cause inaccuracy in the yield monitor.
- On the other hand when we use a multi-point calibration, the red line, we see that it is able to pick up the non-linear trend that the yield monitoring system typically has.
- The big take away from this is that it is important to use a multi-point calibration if your machine is capable. This will better allow for you to catch variations throughout your fields to better pinpoint any trouble areas you may have during harvest.
How Moisture Affects Yield Calibrations
- Moisture is a primary driver of error in yield calibrations.
- If we look at the figure below, we can see moisture on the X-axis and error on the Y-axis.
- We can then see that when the moisture of our grain increases, we are more prone to having higher error within our yield monitoring system.
- To mitigate moisture-related errors in your yield monitoring system, recalibrate whenever the grain moisture content changes by 2%. This ensures your calibration accounts for the typical errors observed at higher moisture levels.
- The calibration needs to be updated every 2% of moisture change to account for density changes in the crop.
Flow Rates
- When calibrating to ensure that you truly catch all crop flow variations you will want to simulate 3 different flow rates.
- These three flow rates will be defined by each OEM during the calibration process.
- Low
- Medium
- High
- These three flow rates will be defined by each OEM during the calibration process.
- Example shown below. For step by step processes visit the Monitor Guides.
System Maintenance
1- Ensure the impact plate shows no excessive wear on the poly or metal, as a worn plate can affect yield readings.
2 – Ensure the tension of your clean grain elevator is set properly. A rule of thumb for the correct tension is to grab the bottom of the chain and slide it side to side while being unable to pull the chain down at all. We see the effects of what an improper tension can do to your yield system’s performance below.