SSE has extended the use of Emerson Process Management’s Smart Wireless technology at its Slough Heat and Power energy facility in the U.K. The new Rosemount Analytical wireless conductivity transmitters are being used to detect changes in boiler condensate conductivity which could be caused by cooling-water leaks in the turbine’s condenser. If left undetected the contaminated feedwater will cause hydrogen embrittlement of the furnace tubes that will result in tube failures.

The 80MW combined heat and power (CHP) plant had previously relied on manual sampling and laboratory analysis of turbine condensate. However, this method caused delays in detecting leaks and as a result the boilers had to be shut down while repairs were made.

Please click to read further 'Emerson’s Analytical Wireless Technology Helps Prevent Unplanned Shutdowns at Power Plant

(By Black Box) Although Ethernet is usually thought of as having a star topology, it’s also possible to build an Ethernet network as a ring. This configuration has the advantage of providing a redundant pathway if a link goes down. A ring topology is often used in application such as traffic signals and surveillance, where long distances may make it difficult to run fiber in a star formation from a central switch and where downtime must be minimized.

The key to the ring topology is spanning tree protocol. One switch-in this case, the switch in the central office-is the root of the spanning tree. A node on the opposite side of the ring blocks on of the ports leading back to the root switch, creating a topology that functions like a long line of Ethernet switches. If a link breaks, the network reorganizes itself to relink all the switches. Although this convergence isn’t instantaneous, it takes only a few seconds to bring the network back. In the diagram below, Hardened Managed Ethernet Switches create a ring topology that operates at Gigabit speed to support traffic cameras at the interaction. Industrial Ethernet Serial Servers make the connection from the switch to the serial interface on the traffic signals, enabling central management of the lights across the Ethernet network.

Case Study by Advantech:

Project Introduction:

Delivering fresh food and beverages to consumers is a popular business, making the logistics of delivering chilled food a multi-million dollar industry. By using refrigerator trucks, logistics companies can transport goods everywhere. However, it is also a challenge to ensure that goods are stored in optimal conditions during transportation as well as being delivered punctually. Therefore, the logistics companies need to build the effective system to help them to closely monitor the goods and trucks.

BlackBox: The PPP, EAP, and 802.1x protocols are often confused with each other, which is no wonder because they’re all interrelated and involve authentication.

Point-to-Point Protocol (PPP) was originally a protocol for connecting and authenticating dialup modems. Today’s PPP is usually encapsulated in Ethernet frames and operates over Ethernet as PPP over Ethernet (PPPoE). PPPoE is commonly used for cable modem or DSL connections to an ISP for Internet access. PPP includes two authentication mechanisms: Password Authentication Protocol (PAP) and Challenge Handshake Authentication Protocol (CHAP).

Extensible Authentication Protocol (EAP) is an authentication protocol framework that works inside PPP to provide support for authentication protocols beyond the original PAP and CHAP protocols. EAP supports a wide range of authentication mechanisms including Kerberos, passwords, certificates, and public key authentication, as well as hardware schemes such as authentication dongles, smart cards, and USB tokens.

802.11x simply takes the EAP framework out of PPP and puts it into Ethernet, packetizing it for transmission over a wired or wireless network. 802.11x has three parts:

• Supplicant: A user who wants to join the network.
• Authenticator: An access point, switch, or other device which acts as a proxy between the user and the authentication server.
• Authentication Server: A server, usually a RADIUS server, which decides whether to accept the user’s request for network access.

When a user tries to access a network through a wireless access point or by plugging into an Ethernet port, the authenticator—usually an access point or switch—consults with the authentication server before allowing the user onto the network.