The second site (Sheffield) of three has been successfully upgraded as part of TasNetworks project to remove unsupported RTU from service.
Prior to the upgrade Sheffield was controlled and monitoring from the Remote Control Centre (NOCS) via two communications protocols, DNP3 and Conitel. Following this upgrade the Conitel RTU consisting of a GE D20M++ was decommissioned, with all of its IO peripheral boards migrated to an existing GE D20EME. The site now communicates with NOCS using only DNP3 via redundant Foxboro SCD5200 gateways, with the modified GE D20EME slaved to these gateways using DNP3 over TCP/IP. The local Citect HMI was modified to integrate with the new arrangement.
Conitel is a bit orientated protocol and requires dedicated hardware in the communications channel to perform bit/byte conversion. Removing this protocol from service will allow the removal of this dedicated hardware (referred to as bit-bashers) resulting in an improved modern platform.
The decommissioned GE D20M++ is a discontinued product by GE and has now been replaced by the D20/D200 Substation controller and the IEC61850 based D400 Substation Gateway RTU.