Many manufacturers have created sophisticated control and monitoring core functions that are embedded in their own dedicated controllers, smart valves and near-edge devices such as smart meters. These intelligent devices are often connected to programmable logic controllers (PLCs) or other centralized controllers to pass data back and forth, which in turn are often connected to PC-based human-machine interfaces (HMIs). systems and the Industrial Internet of Things (IIoT).
Embedded in these near-edge devices is intelligence, which is often the core intellectual property of the manufacturer. For example, a temperature controller reads temperatures, performs PID loops, and monitors alarm set points (Figure 1). It typically connects to a centralized controller or HMI via a serial port and a simple protocol such as Modbus or via Ethernet.
Another example of a near-edge device is an energy meter, which detects energy usage through current and voltage transformers and converts this data into power information, which may then be sent to a centralized controller or HMI.
As near-edge devices become more intelligent, centralized controllers and HMIs are not required in all cases to connect to upper-level computing systems and the IIoT. these near-edge devices already handle the required real-time control and monitoring functions in their embedded platform operating systems, such as Linux or VxWorks.
What many of these devices do not have: a way to bypass the centralized controller and HMI and pass information directly to the upper computing platform and the IIoT. To enable this advanced connectivity, data collection and related functions can often be embedded directly into near-edge devices.
