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The ANSI/ISA95 standard, generally referred to as ISA95, is an important tool for digitalization. It provides the framework, modeling, and vendor independent common information models which can be applied in any manufacturing or process industry production architecture.

The PLCopen organization and Automation.com conducted a joint survey of PLC programming preferences. Here are some of the results to inform you of current trends in PLC programming and users thoughts on vendors.

You may become nerdy programming PLCs, but once you get into it, you won't care. This post is about programming PLCs. Specifically programming PLCs with Ladder Logic. This is what I've done almost daily for my job for the past several years.

It's time to get a little more specific with what the PLC CPU controls: PLC I/O! This article will discuss discrete I/O, analog I/O and briefly introduce industrial communications protocols.

In part 1 of the Beginner's PLC Overview, we talked about what PLCs are, their history, and how they work. This article will get a little deeper into the PLC's Central Processing Unit (CPU).

If you are interested in learning about PLCs and/or PACs, but you are not sure where to start, then this Beginner's PLC Overview blog series has been written for you!

The most common cause of failure or malfunctioning for inverters is an improper installation, often a combination of not following the user manual recommendation and selecting inappropriate cable type, gauges or in line fuses. But there are more.

Kanban is a visual signal that something needs to be replenished. Lean Manufacturers today use Kanban to drive a process to make, move, or buy the appropriate parts. Thus, Kanban becomes one of the fundamental building blocks of a pull (or consumption based) replenishment system. No card? No Replenishment. Paper kanban intent has efficacy; the reality of cluttered transport routes, overflowing finished goods stores, immense quantities of WIP (work-in-progress) and unscheduled machine downtimes, often make the merits of this lean manufacturing functionality questionable. When there are also frequent complaints about delivery problems, the reality is quite distant from the theory. Poor implementation of kanban is quickly overcome in an e-kanban environment. Sue Via, Senior Project Engineer with TechSolve (www.techsolve.org) suggests that Kanban is only part of the lean process, “Kanban is a higher order concept and many things must be in place before implementation of the concept is feasible. For instance, the foundation of Standard Work, 5S/Visual Management, and Quality at the Source must be in place and functional. All affected processes should go through an initial lean transformation to eliminate waste, establish Flow and initiate a Pull mindset. All processes including equipment must be reliable in order to minimize the inventory requirements.” Two of the primary limitations of a manual (or paper based) Kanban system are data availability and scalability. According to Justin Diana, VP of Datacraft Solutions (www.datacraftsolutions.com), “In a typical manual Kanban implementation, most transactions and orders are placed with faxes and emails and recorded in an Excel spreadsheet. At the end of the day, this information is limited to the individual managing and recording this data. The individuals responsible for growing and improving the process, have limited or no visibility to the data. As the number of parts, suppliers, and cells grow, managing this process only becomes more convoluted.” e-kanban, in contrast, focuses specifically on centralizing and managing all of the mission critical data. Real-time transaction capture and tracking builds a repository of information, ripe for process improvement analysis. Allowing an e-kanban system to handle and manage the collation and reporting of this data helps to remove the element of human error prevalent within a manual kanban system. The difference between kanban (a signal to trigger specific quantities of supplies in a just-in-time system) and e-kanban, is working more efficiently and effectively with a lean process. Blanket Purchase Orders, Internal SuperMarket Consumption Signals Replenishment, and Breeding proactive suppliers are three Direct Benefits of Lean e-Kanban. Justin Diana also suggests that, “One other limitation to a manual kanban system is the unpredictable and undependability of the communication... questions such as did they get it? Do they understand it? Am I going to get it? keep buyers awake at night.” Indeed, e-kanban collaboration erases those fears. Electronic records of pull requests, receipt timestamps and electronic acknowledgements all work towards a more unified and dependable method of pull communication. Via suggests that even e-kanban may have limitation in certain environments: “Electronic kanbans are effective when distance is a factor in the process; such as multiple buildings, locations; however, it may be too time consuming when the handoff points are adjacent or close to each other; such as different departments or processing equipment.” Once the discipline and visual aspect of kanban has been implemented internally, the next logical step is to apply the process externally to outside supplying entities. Lean Manufacturing relies heavily on trusted relationships with those suppliers and pre-negotiated terms of engagement. Through the use of quality certification and blanket (long-term) Purchase Orders, the manufacturer can accurately and effectively calculate the optimal level of inventory needed to fulfill demand requirements through the duration of Replenishment lead time. At the end of the day, effective kanban is the sum of a simple calculation. e-kanban products must provide a steady and predictable demand over a forcastable period, supplied by an entity that provides virtually defect free product in the negotiated period of time in the negotiated quantity at the negotiated price. e-Kanban: Vendor requirements When a relationship is setup with a supplier a service level agreement is defined. Items such as negotiated lead times, packaged quantities, order receipt confirmations, and advanced shipment notices must all spelled out very specifically. An e-kanban system monitors that each of these service level agreements are being met by the supplier in real time. If they are not, a series of alerts and notifications starts to be issued to all interested and affected parties. This gives everyone a chance to adjust their behavior to bring performance back in line in real time. e-kanban also captures all of this real time information and makes it available for historical analysis. It is made available over the internet twenty-four hours a day, so that all parties can see trends in performance. Late shipments, short shipments, and other supply chain performances are all captured and presented in terms of percentage of conformance to the service level agreement. These visuals give everyone in the supply chain information about how to focus their continuous improvement energies. e-Kanban: Only one Lean Manufacturing component e-kanban is heavily based on Lean and Six Sigma principles and tools, and the ability to effectively support a production system is critical to Best Practices. e-kanban is a critical Lean element focused on improving flexibility through the elimination of waste; e-Kanban is focused on quantifying the flexibility so that manufacturers and suppliers can rapidly evaluate the true capability of the system to respond to a specific change. Even a Lean production system could struggle to accurately respond to a new order requirement from a customer because it would take longer to identify the source of the constraint and begin resolving it. Implementing pull systems (e-kanban) with more customers is the increasing direction of manufacturing operations utilizing lean. Via argues that e-kanban only makes sense as part of an overall lean process, “Kanban in conjunction with other Lean concepts focuses on Just-in-Time delivery and the reduction of inventories. An effective kanban system requires that all non-value-added activities be eliminated or reduced in order to shrink the required Lead Times.” ***

When interconnecting Ethernet equipment within a control panel, the temptation is to select an office-grade or small office - home office (SOHO) Ethernet switch from one of the mass merchandisers. This equipment is readily available and inexpensive! Since the equipment works at home or on the bench, it should certainly function in a control application. This can lead to large problems in a Building Automation System.

With xPC Target Turnkey, users can do virtual design and debugging of machines, production lines and processes and the results will be automatically implemented in real control systems.

Structured cabling in commercial buildings based on TIA/EIA standards has become a common practice in many building automation system applications. Panduit is promoting similar approaches for industrial automation. Jeff Paliga of Panduit answered the following questions about their approach.

The idea of using a PLC-based system rather than a DCS has become a philosophical and technical debate in the industry. DCSs have been the primary solution for process automation but now many PLC vendors are arguing that a single integrated architecture based on PLCs and/or PACs is the best approach to total plant automation.

Honeywell Process Solutions is pursuing relationships with independent system integrators (SI) for the “Honeywell Experion Implementers” program. I recently spoke with Bill Stevens, Honeywell Channel Manager, to learn more about this program.

Rockwell’s Process Solutions User Group (PSUG) meeting was held the two days prior to Automation Fair. Rockwell’s message to DCS users is very direct - the Logix architecture can meet all control and automation requirements from discrete to process control.

IEC 61850 is the new Ethernet-based international standard for communication in power generation facilities and substations. The goal of this standard is to integrate all of the protection, control, measurement, and monitoring functions within a substation, and to provide the means for high-speed substation protection applications, interlocking and intertripping.

Emerson Process Management introduced their new Electronic Marshalling concept as part of the new DeltaV release. This is the result of Emerson’s new process to design products based on Human Centered Design (HCD).

The standard reference for PID tuning seems to be the Ziegler-Nichols tuning rules developed in 1942 on a pneumatic controller.

To implement a design, Mechatronics Concept Designer generates the control application code in the PLCopen XML standard format to create programs for controllers.

A local area network (LAN) is a private network usually confined to one plant. Virtual LANs (VLANs) allow a single physical LAN to be partitioned into several smaller logical LANs. VLANs limit the broadcast domain, improve security and performance and are ideal for separating industrial automation systems from information technology systems.

The Ethernet-based IEC 61850 international standards for communication in power generation facilities and substations sets a high bar for Ethernet switch reliability. The goal of this standard is to integrate all of the protection, control, measurement, and monitoring functions within a substation.