Ethernet Interface; Redundancy Options - GE 350 Communications Manual

GE
Grid Solutions
SR3 Series Protective Relay Platform
Chapter 3: Ethernet interface

350 Redundancy Options

NOTE:
SR3 SERIES PROTECTIVE RELAY PLATFORM – COMMUNICATIONS GUIDE

Ethernet interface

The Ethernet option for the 3 Series relay provides both a 1300 nm optical interface, and a
10/100 auto-negotiating copper interface. To select which interface is active, a MODBUS
setpoint (see below) must be modified:
MODBUS Hex Description
Address Address
40191 BE EthernetConnectionType
Redundancy options are available for the 350 relay only.
Industrial real-time Ethernets typically demand much higher availability and uninterrupted
operation than office Ethernet solutions can provide. Even a short loss of connectivity can
result in loss of functionality, as for example in some automation, vehicular, power
generation, and power distribution systems.
To recover from a network failure, different standard redundancy schemes are applied
such as Parallel Redundancy Protocol (PRP), High-availability Seamless Redundancy (HSR)
and others.
The basic concept of both protocols, PRP and HSR, is to send practically identical frames
over different paths and discard one of the copies in reception, at best. If an error occurs or
one of the paths is down, the frame travelling through that path will not reach its
destination, but its copy will.
PRP operates on two independent networks. Each frame is replicated on the sending node
and transmitted over both networks. The receiving node processes the frame arriving first
and discards the subsequent copy. The PRP layer is responsible for this replicate/discard
function and hides the two networks from the upper layers. This scheme works without
explicit reconfiguration and switchover and therefore does not show a period of
unavailability.
Min Max Step Function
Code
0 1 1 FC230
Factory
Default
0
3-1