Color Sorter Results Changed? Look Beyond Sensitivity

Get back to the sorting job you need

When your color sorter no longer gives the separation you expect, Metra can help review your grain, equipment configuration and settings. The useful starting point is to separate four jobs: delivering the grain, seeing its color, selecting what to reject and ejecting it. That helps focus the conversation on what changed.

Follow the grain—not just the sensitivity setting

A 6AS sorter moves grain from its hopper through a vibrating feeder and down a chute into an illuminated viewing area. The optical system detects color differences. The controls send a signal to a valve, and a burst of compressed air moves selected material into the reject outlet. Cleaned grain falls into a separate outlet.

Those are connected steps, but they do different work. Sensitivity is an electronic selection adjustment; it is not the whole sorting process. The 6AS manual identifies sensitivity, material flow, automatic cleaning timing and air-pressure warnings as separate functions.

For a useful first conversation, tell Metra what changed in the separation. Is unwanted material remaining in the cleaned grain, or does the rejected material look different than before? Also mention whether you changed crops, lots or settings. These are discussion points—not a diagnosis or an instruction to change several controls.

Separate grain preparation from grain delivery

Grain preparation concerns what arrives at the sorter. Grain delivery concerns how that material moves through it.

The distinction matters because 6AS machines select by color. They do not remove dust from grain or separate material by weight. If the cleaning job includes either of those tasks, discuss the equipment doing that work with Metra rather than asking the color-selection setting to take its place.

Inside the sorter, the hopper flow control and feeder vibration regulate material delivery and output. Those controls serve a different purpose from sensitivity. A useful question for Metra is whether the delivery setup still suits the grain and sorting job you are running.

Metra helps match equipment and configuration to your grain, existing equipment and available space. You do not need to design a replacement cleaning line before calling; start by describing the material and the setup you already have.

Can the optics see the grain clearly?

The viewing system uses lights, a background plate and a lens to detect color differences. The manual explains that dust and impurities can adhere to the viewing glass. Enough buildup can cause false detection and affect sorting accuracy.

That gives optical cleanliness its own place in the discussion. A sensitivity adjustment changes selection; it does not remove dust from the viewing glass. Before treating changed results solely as a settings problem, ask Metra whether the optical-window cleaning system and dust extraction need review for your machine.

There is also an important distinction between keeping the optical area clear and cleaning dust out of the grain itself. The sorter’s window-cleaning system supports its ability to see. It does not turn the 6AS into a dust-removal cleaner.

Any cleaning or maintenance work should follow the instructions for the installed machine and be handled by appropriately trained personnel.

Selection and air ejection are different jobs

Recognizing a color difference is only part of the job. The selected material must also move into the reject outlet. The manual describes compressed-air jets as the mechanism that physically ejects it.

That is why an air-supply concern deserves a separate review. Changing which material the controls select does not establish that the air system is providing the intended ejection. Ask Metra whether the installed air equipment and its settings match your sorter model; do not borrow pressure settings from a different machine.

Metra supplies its optical-sorter package with a compressor, air dryer and air tank. The auxiliary equipment configuration and settings are matched individually to the model. For an existing installation, the useful question is what equipment is actually connected and whether that arrangement needs attention—not simply whether a compressor is present.

Bring the setup back to the intended selection

The goal is to identify which part of the process needs attention, then discuss the appropriate model-specific support. For the 6AS-680, Metra offers local and remote tuning and operator training. Discuss the arrangements with Metra for your installed machine.

Tell Metra your model, which grain you are sorting and what changed in the separation. The team can help review equipment selection and settings, and discuss whether testing a representative sample or arranging a warehouse demonstration would help show the intended color selection on your material.

Explore the 6AS-680 or Metra optical color sorters, then contact Metra at 701-515-0488 to discuss your setup and arrange the next step.