The heart of the AccuMix™ 750XB is its control system. An Allen-Bradley SLC 5/05 Programmable Logic Controller and Panelview Plus 1250 12.1” color active matrix Operator Interface is directed by Gears, Inc.’s proprietary AccuMix™ control software. Designed for harsh industrial environments, this versatile and reliable system has extensive self-diagnostics and is completely modular, making diagnosing and repairing problems as easy as plugging in a new module.
AccuMix™ software provides fully automated plant control and monitoring of all plant systems including engine, flow meters, sensors and switches. Displays indicate all flow rates, set points, feeder speeds, totals and status of all feeds and processes. All critical mechanical systems are monitored to alleviate damage and prevent down time. Inventory of fine particulate and admixture are computed and tracked. An Epson RS232 multi-copy printer is provided and will print mix design, inventories, rates and totals, either on demand or on a mix time interval. All electronics are accessible via an Ethernet/IP network and with optional terminal can be controlled and monitored remotely.
Start up sequence is automated to start all components in proper order and all mix ingredients are interlocked and will start simultaneously. Mix proportions may be controlled one of three ways. First, they may be controlled manually by entering the desired feeder speed. Second, the desired feed rates may be entered and the AccuMix™ software will maintain them. Third, the desired final product rate and a mix design may be entered. AccuMix™ software will then calculate proper proportions and maintain feed rates. Mix design is entered by specifying each dry particulate additive as a percentage of dry aggregate weight, admixture in gallons per ton of final product and mix moisture as a percent of all dry materials. Entering the mix design in this way maintains the crucial proportion of dry materials and admixture, regardless of moisture changes. This is very important because the aggregate stockpile moisture will vary through the day plus evaporation in transport will require varying the final mix moisture. The operator continually updates the desired mix moisture and the Hydo-Probes update the stockpile moisture. AccuMix™ software uses this information to compute dry aggregate weights and to add the proper amount of water to achieve desired output.
All material hoppers are equipped with empty bin indicators tied to mix shut down. Ingredient feeder control loops are monitored and adjusted every 2 milliseconds for fast accurate proportioning of feed materials and will shut down the mix immediately if proportion is not within specifications. When plant control is by mix design, the combination of these functions and the consistency of the feeders results in proportioning accuracies of better than ± 1/10 %