Advanced PoE Empowers the Latest Smart Solutions
October 11, 2019
The champion in the professional space is Power over Ethernet (PoE), which is actually a kluge to send electric power along with data on twisted-pair Cat 5 Ethernet cabling.
Most consumer attention in the intelligent systems space is focused on the new cool devices available, and the vast array of functionalities they provide. However, anyone in the electronic design space knows there are a lot of wires and cables in the infrastructure in the wainscoting supporting all this wireless magic. Even in fixed facilities, where wired peripherals are the norm, the amount of cabling seems to be growing exponentially.
One way to significantly reduce the amount of wiring in a system is to use the same cables for signals and power. This reduces everything from the number of cables per device to fewer ports needed in the device itself. The current winner in the consumer space is the ubiquitous USB, but the champion in the professional space is Power over Ethernet (PoE), which is actually a kluge to send electric power along with data on twisted-pair Cat 5 Ethernet cabling.
The original PoE standard, IEEE 802.3af, allowed for a maximum of 15.4W over two pairs of a four-pair cable, using pairs 1 and 4 or pairs 2 or 3, but not both. The current iteration of the standard however, 802.3bt, offers two power variants: Type 3 for up to 60W, and Type 4 for 90W, taking advantage of all four pairs in a 4-pair cable, spreading the current between them. In this version, the power is delivered from the source equipment after a negotiation with the powered device (Figure 1).
Optimizing energy management by enabling Powered Devices (PDs) to transmit their power needs through the charging cable to the Power Sourcing Equipment (PSE) is a force multiplier in a system. The negotiation between devices enables each PSE to allocate the exact amount of power to each PD, maximizing both available energy and bandwidth.
This improved capability is increasingly being realized by manufacturers in their solutions, and the result is better, higher performing, and more reliable and safe networks. For example, ON Semiconductor’s latest offerings support the increasing power demands of IoT endpoints. The IEEE 802.3bt-compliant solution delivers up to 100 Watts of power over Local Area Network (LAN) connections.
Forming the foundation of ON Semiconductor’s PoE-PD solutions, the NCP1095 and NCP1096 Interface Controllers (Figure 2) incorporate all of the features needed to implement a PoE interface, including detection, auto-classification, and current limiting. The controllers are complemented by the NCP1566 DC-DC Controller, the FDMC8622 Single MOSFET and the FDMQ8203 and FDMQ8205A GreenBridge Quad MOSFETs, enabling PoE interfaces with up to 90 Watts standard, or to a proprietary 100 W solution if more power is needed.
A smart industrial facility is full of panel PCs and other control and management devices and interfaces. The ability to convert or upgrade existing devices to the new PoE paradigm is also very useful. Recently ICP Germany announced their AFOLUX AFL3-AL GEN III series of panel PCs is available with a PoE upgrade option (Figure 3) compatible with IEEE802.3at or bt standards. Using an added module, PoE functionality is provided and the family of 10.1-inch to 15.6-inch panel PCs can be operated without an additional power supply.
Based on an Apollo Lake Intel Celeron J3455 processor with up to 8GB DDR3L memory, the PCs have a 2.5-inch SATA 6Gb/s hard disk frame and an M.2 slot for data storage or as an E-Window extension for implementing additional interfaces such as LAN, DLAN, Profibus or EtherCAT. Depending on the display size, one RS-232/422/485, one RS-232, two USB 3.1, two USB 2.0 and one HDMI are available. These products will be shown at the SPS exhibition this November in Nuremberg.
The more varied the solutions available, the more creative designers can be in the generation of their solutions. The new IEEE 802.3bt standard is only beginning to hit its stride this year, and that will accelerate as more compliant devices are made available. Analog Devices is in the process of launching a portfolio of Industrial Ethernet solutions to address communication challenges within Industry 4.0 and Smart Factories (Figure 4). Encompassing a range of novel Industrial Ethernet technologies, the solutions can create robust, scalable Ethernet connectivity solutions.
The company will have various live demonstrations at the SPS event in Nuremberg in November to showcase their solutions in interactive examples. One of the demonstrations will focus on enabling Ethernet to the Field and will show the new IEEE P802.3cg/10BASE-T1L physical layer standard communicating over 1km of single twisted pair cable, resulting in digitization of process measurements and control.
The quality of the cabled infrastructure required to empower the latest in advanced Cloud, automation, and smart building applications is a critical factor in performance and reliability. Single-cable power and signal connections are important to ease integration and cut down on unnecessary wiring, with the added benefit of reduced system complexity and cost. Using the latest PoE solutions in your system architecture will pay off handsomely at every level, with cascading benefits.