Ethernet is the broadly accepted standard for wired digital communications. The Ethernet Advanced Physical Layer, or Ethernet-APL provides the infrastructure for the field of process plants with:
- Long cable runs with two-wire cable
- Power and communication on the same cable
- Support of all types of explosion protection including intrinsic safety
- Simple installation technology
- Resilience to electro-magnetic interference
Ethernet-APL supports all safety protocols that are based on the black channel, where the infrastructure for digital communications is precluded from safety assessments. The considerations remaining for network designer is to evaluate and provide the required, high standards for reliability and availability. This requires careful consideration network structure and reliability of hardware. More importantly the system should be fitted with diagnostics even of the infrastructure itself to detect manual intervention or human error, as these are more likely to impede communications compared to spurious failure of hardware.
In explosion-hazardous areas, the power distribution is installed with increased safety. This protection already affords users by itself with extremely high reliability, as the cable and connections require protection against unintentional disconnect. Other aspects for implementation are: Redundancy of auxiliary power and of the back-haul connection, which can be implemented with fiber optics.
Networks carrying safety-related signals should be fitted with diagnostics of the network and the physical infrastructure. This insight provides detection of unwanted conditions – in many cases prior to such conditions becoming detrimental to communications and potentially causing the plant to go into safe mode. Diagnostics enable data-driven, targeted and proactive intervention. They put plant service and management teams into the position to take remedial action in a timely and effective manner and protect from unwanted downtime.
With large temperature variations and rough ambient conditions, planers and operating personnel are well advised to rely on suppliers that can provide ruggedized infrastructure. Products should provide a long service life. Pepperl+Fuchs is the long-standing expert for any infrastructure in the field of process plants. With their first FieldConnex® switches this tradition now extends to Ethernet. These switches provide 8, 16, or 24 ports for Ethernet-APL plus redundant RJ45 and fiberoptic ports for constructing highly available ring topologies. Diagnostics, which are included as standard, monitor the health of the switch itself and most importantly the entire physical layer to the safety instrumentation. High availability of the network infrastructure is ensured!
Find everything about the infrastructure and Ethernet-APL at: www.pepperl-fuchs.com/apl