September 2013, Vol. 240 No. 9

Features

Using Cellular Automation To Monitor And Control Assets

Today’s utilities have a highly productive and efficient business environment that is very competitive and needs to comply with many stringent regulatory requirements to prevent situations that would cause a facility to be down for even a short time.

A slight failure of equipment translates into immediate consequences from both a financial and safety perspective. These pressures move utilities toward building high-availability smart sites that help minimize unscheduled down time and allow for shorter time to repair.

A direct result of this trend is the need for the site to have remote access to equipment. To help facilitate this access, utilities are converting networks to become IP-enabled – but with the many benefits that come with this, the move to IP networks also adds a level of complexity as it becomes increasingly important to securely connect these critical industrial infrastructures. To that end, cellular automation enables cost-effective monitoring and control of data at remote sites.

Controlling Data At Remote Sites
For the most part, remote sites with critical equipment are located in places that are difficult to access due to long distances or harsh conditions. Accessing critical information, such as equipment health and operational data at these sites can be time-consuming and costly. Also, given today’s aging industrial infrastructures, monitoring and controlling the data within these sites is more critical than ever. In fact, we are beginning to witness the consequences of not updating and maintaining outdated networks, as demonstrated by recent explosions at gas pipelines and blackouts in major cities when parts of the electrical grids have gone down.

Keeping a closer eye on these infrastructures is necessary not only to prevent loss of revenue, but more importantly, loss of life. Unfortunately, however, communicating with remote sites to proactively prevent equipment degradation is far from an easy task and may even require a four-hour helicopter ride. In order to proactively monitor and control remotely located assets, users must be able to access local sensor data. The most cost-effective and intelligent way to do this is through cellular automation.

Using Cellular Automation
Cellular automation is the concept of providing remote terminal units (RTU) with cellular connectivity to access data in hard-to-reach locations. Cellular connectivity provides fast and easy access to monitor and control business-critical applications at remote sites. This flexibility, however, also requires a level of responsibility that requires enhanced security requirements as well. In some cases, this is new ground for many users, as data security is something that many customers did not focus on in the past since they were using direct circuit connections via modem banks.

These types of connections did not require the same stringent security standards that a cellular connection over an IP network does. Therefore, as customers migrate toward IP networking and data security is mandated, sourcing and implementing new technologies to support the increasing security demands becomes necessary.

In addition to addressing more stringent security requirements, industrial users face the complexity of having multiple devices to manage and implement for an effective remote monitoring and control solution over IP. The challenge facing many customers is that, on top of their existing RTUs, they must also figure out which of many products they will require. It may be necessary to have a device for cellular connectivity, a Modbus gateway and a security (VPN) device, which is costly to deploy and complicated to administer and maintain.

A cellular automation solution dramatically simplifies this task by integrating automation, routing, security and cellular technologies into one hardened package. A built-in Modbus gateway easily interfaces with existing RTUs and PLCs and provides real-time access to data from pumps, valves, reclosers, transformers, capacitor banks and meters.

For industrial applications, such as oil and gas, power and energy, and water and wastewater renewable, accessing data in real time and keeping network links up and running is critical. More stringent security requirements, such as EPA and NERC, must also be supported as the network continues to evolve. Additionally, an integrated firewall that provides stateful packet inspections, as well as filtering of IPs via access control lists or NAT, is needed to avoid new threats.

More specifically, it is necessary to have integrated user firewall configuration rules that restrict the type and duration of access to authorized individual, user-based permissions and encryption of data to provide adequate security for business-critical applications.

Comparing Alternative Solutions
Short messaging service (SMS)-based solutions are another lower-cost alternative that some companies have chosen to implement. Although this approach may be effective and easy to use, it has inherent risks. Texts are a powerful means of attack because the devices that receive them generally cannot refuse them or the commands encoded in them. The problem is that users are unable to block unwanted texts, which means they are unable to prevent someone from sending commands through text messaging and throwing off the device.

Other approaches include modem-only equipment solutions. This type of solution involves adding a cellular modem to existing equipment. While this approach does provide the ease of cellular connectivity, the lack of security options on most cellular modems leaves the network open to attacks.

A good cellular automation solution based on TCP/IP networking provides anywhere/anytime connectivity and also offers security features that meet the most stringent requirements of industrial standards associations. Cellular automation is a cost-effective solution to customer problems, which integrating cellular data networking to enable SCADA data to be securely communicated from the remote site back to the control center, thereby improving safety, productivity and profitability.

Today, most – if not all – remote sites contain legacy serial devices that need to be converted to IP-based services. Some of these devices require special treatment by the gateways they are attached to so that the serial interface can be properly converted to IP, but most solutions don’t offer that type of flexibility.

A cellular automation solution enables smart remote-connected sites by protecting RTUs, PLCs and other HMI equipment, while also making mission-critical data from variable frequency drives (VFDs), pumps, valves and motors securely available in near real time. This solution also eliminates costly visits to remote sites for minor software changes or failures. This translates into large savings for customers using cellular automation for remote support.

Integrated Software Development Kits
Another critical element of an effective cellular automation solution is an integrated software development kit (SDK). Today’s highly efficient environments demand product flexibility that allows users to customize for the site’s needs and provide software that enables customer-specific applications to run on the same integrated product. An example of this would be custom software code, which is designed to extract specific types of data and formatting for special reports. In the absence of having the ability to custom-program, a lot of time and resources will be used in trying to support the application.

In order to most efficiently address the challenges of remotely monitoring and controlling today’s industrial networks – which require support of legacy serial-based equipment (MODBUS RTU) plus the need to add next-generation IP based (MODBUS TCP) – an integrated and cost-effective solution that supports both environments within a single hardened platform is required. The additional complexities of managing multiple remote locations require that smart sites have easy-to-configure software that can be remotely configured and managed.

The goal is to allow users to locally do everything that they can do remotely. This means that robust device management software that provides everything from health statics and connectivity information to remote configuration and mass device configuration is required. A smart remote site connected via a cellular automation solution provides the ability to reboot and control the equipment without requiring a technician being sent to the site.

Smart remote connected sites protect RTUs, PLCs, HMIs and process control equipment using a secure, easy-to-configure solution that is integrated into one cellular automation device.

Author Note:
This article was prepared by Red Lion of York, PA whose product brands include Red Lion, Sixnet and N-Tron.