Real-time Efficiency Data Collection

By: Steven Noto, Process Technologies Group, Inc.
Topics: Downtime Tracking, Efficiency, OEE, Data Collection, IMPAX TSS

PLC-based data collection system for reporting on efficiency and overall equipment effectiveness

Process Technologies Group, Inc. (PTG) is a designer and manufacturer of process monitors, piezo-electric force sensors, and data collection software. Its patented IMPAX process monitors are used extensively in the metal forming and metal cutting industries, with over 6000 installations. Critical to understanding and improving a shop's productivity is finding out how often and why machines go down. Manufacturers may not track this information at all, or may do it manually, requiring the operator to make notations of downtime and reasons by hand. This can result in poor or inconsistent data that is difficult to analyze. PTG's solution to their customers' need for reliable production and downtime data from the shop floor is a PLC-based system that can be installed on a per-machine basis to operate stand-alone or networked with a data collection and reporting system.

The IMPAX TSS Machine Efficiency Monitor utilizes a micro PLC and a touch panel operator interface as the heart of its monitoring and data collection functions. The PLC analyzes digital and analog input signals from a variety of sensors or machine controllers to determine the status and speed of the process. It tracks and displays production totals, tool life, machine speed, efficiency data, and accumulated shift uptime/downtime. In the event of a machine/process stop, the unit automatically converts to downtime entry mode. Operators must use the touch panel to select from pre-defined downtime reasons in order to restart the machine, so all downtime information is accurate. All occurrences of downtime, and the corresponding reasons, are archived in the system as well. The TSS system also calculates O.E.E. (Overall Equipment Effectiveness) in real time. This not only simplifies satisfying the O.E.E. reporting requirements of firms such as Honda, Toyota and Nissan, but it also enables the user to react to negative performance trends before it's too late.

The archived data in each TSS system can be transferred over a network into a PC database for further evaluation and customizable report generation. Software available to a manager then display a summary of downtime occurrences and total time for each downtime reason. The built-in RS-232/422/485 port on the PLC allows serial networking, and PLC's low-cost Ethernet option allows faster and communications, that are easier to set up. These PLCs are often more cost-effective and easier to implement than a conventional data collection system. The Ethernet module connects the PLC to an Ethernet network for a very low cost per node, giving even the smallest plant an easily affordable data collection system.

The IMPAX TSS Machine Efficiency Monitor has been installed in shops of 10 to 100 machines. Although originally designed for the fastener-making industry, the system is applicable to any factory or shop floor where machines generate parts or process materials. Currently PTG has prospective customers looking to use the IMPAX TSS for metalworking, bottling and textile machines.