Standards Development

Scope

This document will specify the requirements for the Binary Input Output IED (BIOI), which is a physical binary process interface device intended to be used in a protection, automation and control system (PACS). The BIOI provides an interface between the wired connection based substation equipment (typically a primary switchgear) and the PACS functions via a process bus of the IEC 61850 communication network. It is used as physical process interface for protection, control and other IEDs using IEC 61850 GOOSE messages. This covers physical binary inputs and outputs with any substation equipment e.g. positions and commands for circuit breakers and other switchgear.

This document will cover the requirements and related testing of the BIOI for the:

 • Digital interface

• Related internal functionality

 • Wired binary process interface

For the digital interface this document will cover in particular:

 • Subscription to IEC 61850 GOOSE messages (e.g. trip signals, controls commands)

 • Publication of IEC GOOSE messages (e.g. circuit breaker position, circuit breaker ready to close failure)

• IEC 61850 MMS client/server services

 • Time synchronisation

• Engineering interface to comply with SCL engineering process

Requirements regarding characteristics of the communication network are not within the scope of this document. The communication interface is also not included in this document is defined in IEC 61850.

The PACS communication network engineering and cyber security measures to be applied on PACS level are out of scope of this document.

Purpose

Process interface for analog values have been standardised for several years (SAMU – IEC 61869-13 developed by IEC TC38). The BIOI is another important process interface equipment for fully digital, process based Protection, Automation and Control Systems. IEC TC95 has developed General requirements for protection functions interfaced with IEC 61850 (IEC 60255-216-2).

 ACTAD (Advisory Committee on Electricity Transmission and Distribution) has asked TC95 to lead the development of this standard (see ACTAD/135/RM clause 7.4 and SMB/6625/R item B.2).

 IEC TC95 approved development of this standard in the last Plenary meeting held in Largo (US) in February 2024 (See 95/572/RM item 8.10 and 95/570/DL decision 2024/09).

The standard will be developed in close collaboration with IEC TC57 (taking into account prIEC TR 61850- 90-29) and with IEC TC17 regarding the IEC 61850 modeling of circuit breakers and disconnectors.