Verify TMR mixer scale accuracy (Emily Templeton)

By Emily Templeton, Vita Plus forage summer intern
If it’s not one thing, it’s another when it comes to the up-keep on machinery around the farm.  It’s essential that we take good care of our equipment so it can last longer and we can save a few dollars down the road.  But are we looking past one of the machines that we use on a daily basis, rain or shine?

This summer, I visited more than 40 farms as part of a Vita Plus scale pad project.  The purpose was to check the scale accuracy on TMR mixers.  It is very important to have an accurate reading because we depend on it for so much.  If we take the time to take feed samples, make a ration, calculate dry matter intake, and then find out the mixer scale is way off the mark, our efforts may go for naught.

During this procedure, we set up two large portable scale pads at each farm on a flat concrete surface.  The tractor/truck and empty mixer were then pulled onto the pads and each axle was weighed, including the tractor/truck axles.

Once the weights were complete, the mixer was filled with a normal TMR mix and re-weighed.  The empty and full weight process was done twice to verify that our scale pads were weighing consistently.   From the data collected, we evaluated only the mixers that had an empty weight difference of 2 percent or less to verify those empty weights.

After compiling all of the information, we noted a few mixers had significant inaccuracy. Many others were verified as extremely accurate.

In some cases, the mixer scales need to be recalibrated, but that’s not usually the first thing we should point our finger at.

More often, the inaccuracy is due to the mixer itself.  This could be due to a mechanical issue, such as the binding of a weigh bar, or an electrical issue, like a loose or old wire.  The first area to troubleshoot would be to corner-check your weigh bars or load cells with a known weight.  If the scale reads correctly, calibrating is not the answer.

For further troubleshooting, contact your TMR mixer or scale company, assuming the problem is underneath the mixer.

More information from this project will be shared as we continue to evaluate the data collected.  Stay tuned for those details.