Coal Fired Power Plant


One of our customers recently built a new coal fired power plant, requiring automated, unattended weighing of inbound coal. Trucking was being done by third party, with fleet of trucks dedicated to this customer. Customer wanted to maximize the efficiency of each truck, in order to maximize the number of trips each truck could make each day, as well as minimize the total number of trucks required to meet demand. Additionally, truck scale would be located at entrance to facility, over 1 mile from their control room, where the operator would manage the truck scale, among other tasks. Facility required secure, 24/7/365 operation of scale system, which involves temperatures from below 0°F to +120°F.


Unitec was brought into this project at the design stage, and was involved as a collaborative partner in the general design of the weighing and automation solution.

The first consideration in this project is with selection of truck scale design. Because of the industry and environment the scale would operate in, the Low Profile Above Ground scale was determined to be the optimal scale for this application, and was spec’d into the project. This scale design was deemed most effective for this application for specific reasons–the proven Unitec Low Profile design (field tested); the benefit of the outboard load cell suspension would keep load cells out of the mud and debris, maintain scale performance even when the ground froze; the side rails were a necessary safety feature while their integral design provides added structural durability.

the The second part of this solution was the automated, unattended system. This system needed to be user-friendly from the truck drivers perspective (intuitive and fast, operating 24/7/365), accessible by plant management and operations personnel and able to be supported from a remote location. The system needed to manage a specific, repeated task, while offering the administrative and reporting flexibility required by the management of the facility. The trucks were outfitted with long-range ID Micro RFID tags (able to operate in extreme temperature range, also able to process bi-directional weighing from single reader), allowing the trucks to be identified while entering the scale, with drivers processing the transaction once they stopped next to the scaleside terminal, taking a ticket and proceeding to their off-loading location. This minimized transaction time, and maximized efficiency.

Because of Unitec’s unique relationship as a Systems Integrator for Interface Logic Systems software solutions, the ScaleQ Scale Management and Control solution was determined to fit these requirements. ScaleQ would manage the scale transactions and unattended weighing processes, while Unitec would provide the integrated scaleside hardware (unattended truck scale terminal, RFID, traffic lights, wheel sensors, etc.) and the Systems Integration for the entire project. ILS would provide developer-level support and Unitec would provide field-level, and front line support. With Unitec personnel able to install, configure, test and train on both the truck scale and the ScaleQ system, installation efficiency was maximized.