Removable data storage reaches the plant floor
High-volume data storage capabilities have become an ever-increasing need for plant engineers and automation professionals. These and other individuals working in the industrial sector are constantly looking for ways to improve their control system architectures, make their industrial networks perform better and lower the cost of ownership of the same.
High-volume data storage capabilities have become an ever-increasing need for plant engineers and automation professionals. These and other individuals working in the industrial sector are constantly looking for ways to improve their control system architectures, make their industrial networks perform better and lower the cost of ownership of the same. Removable, portable storage solutions such as the USB “thumb” drives and microSD flash memory cards that are commonly used with consumer products such as personal computers, cameras and mobile phones, have made their way to the plant floor and can now be used with latest generation PACs, PLCs and other industrial controllers.
One of the key features of modern PACs is their utilization of industry standard communication and networking interfaces, which enable a free and easy exchange of data. Data storage capability is one of the main features consumers evaluate before they purchase cameras and other electronics — and automation professionals are catching on to this as well. When selecting control system components for their systems and facilities, they know they can use removable storage for many purposes, including updating and testing firmware on their controllers, distributing new control programs and storing process control and machine data.
Just a short time ago, data storage for industrial applications was a much more limited proposition. There was no way to store large amounts of information locally on a controller, so any data that needed to be archived had to be ported to an HMI or database running on a PC. Subsequently, if any of that data needed to be uploaded or accessed, the PC and the database it hosted was absolutely essential.
Furthermore, any non-networked controllers or devices had no way to easily archive data. To accomplish this, engineers and technicians needed to physically connect a laptop to these controllers. This same method was used for firmware upgrades. A non-networked device had to be deactivated, connected to, the new firmware uploaded and the device rebooted. One can imagine how labor-intensive this was (and in many cases still is) for plant engineers and others with several remote units deployed. Although custom “black boxes” and specialized data acquisition I/O modules emerged as data storage solution alternatives, these were often expensive, required extra programming, took up valuable real estate on an I/O rack or panel or were otherwise problematic.
Addressing users’ needs
Today, PAC vendors and other manufacturers of industrial hardware have addressed users’ data storage needs (and solved many of the surrounding issues) by adding removable data storage capabilities to their controllers. Rockwell Automation’s Logix systems, Schneider Electric’s Modicon controllers and Opto 22’s SNAP PAC systems, for example, support microSD cards or other forms of removable flash memory. Support for these memory cards — some of which are custom, others are the same as you’d find in your local Radio Shack — demonstrates these vendors’ commitment to providing engineers with an integrated, low cost and familiar storage solution for their projects.
Removable flash memory is small, cheap, non-volatile, durable and high capacity. This gives users an easy way to record tremendous amounts of process, operational and I/O data. A PAC equipped with a microSD card of just a few gigabytes can potentially store months or even years of data. Remote and non-networked controllers can be programmed to collect data indefinitely until personnel can be dispatched to retrieve the memory card.
Removable storage for industrial controllers can also be used for control program testing and updates. A microSD card or thumb drive can be used to distribute, test and swap out control programs quickly and easily. This gives engineers a new way to experiment with process efficiency or provide proof of concept for their ideas.
Removable storage can also be beneficial to machine builders, OEMs and others working with controllers embedded in enterprise equipment, machines and systems. Simply inserting the storage device with the new firmware into the controller provides a convenient way to update devices in the field.
Hopefully, vendors will continue to incorporate off-the-shelf storage technologies into their products, as the futures of microSD, the soon to arrive USB 3.0 and other data storage solutions promise removable media that’s smaller, more than ten times faster and has even greater capacity.
|David Crump is marketing communications manager at Opto 22.|