The explosive growth and continuing evolution of Industry 4.0 have been providing electronic design engineers with lots of opportunity, but also lots of headaches. Trends like Industrial IoT (IIoT), Edge computing, and the expansion of intelligent systems, coupled with the coming integration of Artificial Intelligence, are constantly changing the design landscape.
Deciding which Single-Board Computer (SBC) to integrate into your industrial design is far from a no-brainer partly due to the wide spectrum of available solutions. In previous blog posts, I covered important aspects in SBC selection such as software and operating system support, performance and connectivity in an industrial setting, and overall cost. Here, I’ll look at often overlooked aspect of embedded systems, namely power.
There are no electronics without electricity, yet you could argue that power electronics and energy management in system design have only come into focus fairly recently. Designing for energy efficiency is far more than just making sure you have an efficient power supply; every subsystem and its energy consumption and use are factors in overall performance.
A significant issue in industrial systems is the need for a good hybrid power/signal interface. Running one cable instead of two makes sense in a lot of ways, from reducing the number of connectors to saving on additional labor and materials. Since there’s currently no industrial-grade standard power/signal interface, designers are leaning on existing solutions.
The two leading hybrid power/cable interfaces in use today are Power over Ethernet (PoE) and USB. Each has been hardened and upgraded to address industrial systems. There are also proprietary connector/cable systems from leading manufacturers that can better address industrial applications, but at a higher cost. Industrial PoE (IPoE) is well suited for use in advanced smart facilities, as it allows high data rates and power levels.
SBCs compatible with IPoE systems typically require less effort to design in, and operate using a well-known interface. However, to properly operate in an industrial environment, all IPoE equipment should withstand temperature ranges around -40 to 75 ºC.
One example of the kind of SBC that can operate in an IPoE environment is the WINSYSTEMS’ SBC35-C398Q, a quad-core i.MX6-based embedded computer which can be powered as an Ethernet PoE-PD device. The single board computer then provides support for numerous I/O for data acquisition or control through six USB, two CAN ports, five serial ports, and 24 GPIO.
Another example, the PPM-PS397-POE isolated 25-W, PC/104-Plus form factor, 802.3af/at compliant, PoE PD power supply supports up to twice the power of 802.3af compliant PD devices. It’s designed to power an SBC and PC/104 stack from a CAT-5 cable sourced by an 802.3af/at compliant PSE device configured as either an endpoint or midspan device.
The PPM-PS397-POE-1 accepts ±42 to ±57 VDC and has three output rails: +5 VDC to 5.0 A,
+12 VDC to 1.0 A, and -12 VDC to 500 mA. The PPM-PS397-POE-1 can alternatively take power from a 16 – 60 VDC auxiliary input instead of the PoE interface. The auxiliary input is dominant. When present, it will always power the PD regardless of the state of PoE, not drawing power from PoE. The auxiliary power input is hot-swap capable.
Power electronics and energy management aren’t the first thing that engineers consider when designing-in an SBC, but how the system accepts, manages and uses power is instrumental to its final functionality and performance. Issues like operating temperature range, energy efficiency, and power protocol compatibility are key to a good design.
George Thomas “G.T.” Hilliard joined WINSYSTEMS in 1994 and has over 25 years of professional experience assisting clients to solve technical challenges. George has a BS in Electronic Engineering Technology and previously worked at a Fortune 500 company where he provided technical support for industrial control and sortation systems. Starting as an Application Engineer, George now leads the sales and marketing departments where he continues to enjoy supporting clients in solving technical and business challenges.