New HIDS Drum Scales!
Click Here to Learn More!It is good to verify any new rate or weight calibration, because this is the basis of any loss in weight system.
Prior to running the rate calibration for a new product, clean the area around and on the scale. Check all connections to insure they are properly installed and not causing mechanical problems.
Using a test weight of a known value is a good way to verify your weight calibration and rate calibration is correct. Rate calibrations can look perfectly OK with a bad weight calibration, but the rate accuracy will be severely impaired. The scale calibration may have been originally certified, this step is to ensure the scale is still conforming. Maintenance weight verifications are not as critical as the periodic certification to ensure the scale is in exact working order. So, after a good weight calibration, pick an object that is near the low weight range and place it on the scale. This way, if a load cell goes bad or there is a mechanical bind, the verification weight reading will not be correct. A small test weight should be in the range of +/- 0.2%. Place it in the center or as close to the center as possible and you should place the weight in the same position every time you verify the scale calibration prior to a rate calibration.
After running the automatic rate calibration on the HI2160RC, you can verify the rate calibration was successful.
The percentage of the high and low rate calibrations are a fair indication of the process condition.
10% and 90% indicate the rate calibration is in progress.
20% and 80% indicate a failed, incomplete, or never run rate calibration.
30% and 60% indicate the rate calibration was completed, but is not an indication of a good rate calibration.
The best method is to make a short timed sample catch of your product and verify the weight on a small certified scale. Did the amount of product captured equals the product per time period setting?
Some causes of poor rate calibrations are due to poor scale calibrations, mechanical obstructions, and feeder and configuration problems.
On the HI 2160RC; During the auto rate calibration, data is collected and the results are stored under the self-test menus. These results are a 2-Sigma type test which will help determine the feed rate accuracy at the five different levels of the auto rate calibration. This feature is only available on the HI 2160RCplus controller.
After exiting properly from the Rate Calibration menu to the main screen, perform the following from the front panel:
Press the TEST button.
Arrow to the self-test selection, (middle)
Press ENTER (These screens display the controller system configuration information)
Press the down arrow to see both pages of the test percentages.
Verify all the percentages are less than +/-25%.
If all looks good, you have completed a good rate calibration and may proceed.
If the percentages are much higher than 25%, inspect the feeder, scale, and all hardware attached to the feeder. Correct any problems found and re-run the rate calibration. The problem could be product related, mechanical, electrical, operational, or corrupted controller memory. Verify the scale calibration is good and restart the auto rate calibration.
Rate calibration is the most important element of the loss in weight controller. This process establishes the calibration slope and starting rates and accounts for most of the bad batches and totalizer errors disagreements.
If the scale system has been running correctly and then fails at this time, inspection and testing can determine the problem. If this is the first time or a startup there are additional articles under Web tech to help determine if the weight to rate ratio is viable, setup suggestions, and configuration changes that can help.
With the HI2160RC now obsolete the replacem
