Year: 2026

Mounting methods

•Flush mounting

•Semi-flush mounting

•Semi-flush mounting in a 25° tilt

•Rack mounting

•Wall mounting

•Mounting to a 19″ equipment frame

•Mounting with an RTXP 18 test switch to a 19″ rack

Panel cut-out for flush mounting

•Height: 161.5 ±1 mm

•Width: 165.5 ±1 mm

Relay case and plug-in unit

The relay cases are assigned to a certain type of plug-in unit.

For safety reasons, the relay cases for current measuring relays

are provided with automatically operating contacts for short

circuiting the CT secondary circuits when a relay unit is

withdrawn from its case. The relay case is further provided with

a mechanical coding system preventing the current measuring

relay units from being inserted into relay cases intended for

voltage measuring relay units.

Selection and ordering data

The relay type and serial number label identifies the protection

relay. The label is placed above the local HMI on the upper part

of the plug-in-unit. An order code label is placed on the side of

the plug-in unit as well as inside the case. The order code

consists of a string of letters and digits generated from the

relay’s hardware and software modules.

Mounting methods

By means of appropriate mounting accessories, the standard

relay case can be flush mounted, semi-flush mounted or wall

mounted. The flush mounted and wall mounted relay cases can

also be mounted in a tilted position (25°) using special accessories.

Further, the relays can be mounted in any standard 19”

instrument cabinet by means of 19” mounting panels available

with cut-outs for one or two relays.Alternatively, the relays can

be mounted in 19” instrument cabinets by means of 4U

Combiflex equipment frames.

For routine testing purposes, the relay cases can be equipped

with test switches, type RTXP 18. which can be mounted side

by side with the relay cases.

Local HMI

The relay is equipped with a four-line liquid crystal display.

Depending on the chosen font and language, the number of

visible lines may vary. The display is designed for entering

parameter settings of the protection and control functions. It is

also suited for remotely controlled substations where the relay

is only occasionally accessed locally via the front panel user interface.

The display offers front-panel user interface functionality with

menu navigation and menu views. Depending on the

configuration, the relay displays the related measuring values.

The local HMI includes a push button (L/R) for local/remote

operation of the relay. When the relay is in the local mode, it can

be operated only by using the local front-panel user interface.

When the relay is in the remote mode, it can execute

commands sent from a remote location. The relay supports the

remote selection of the local/remote mode via a binary input.

This feature facilitates, for example, the use of an external

switch at the substation to ensure that all relays are in the local

mode during maintenance work and that the circuit breakers

cannot be operated remotely from the network control center.

The IEC 61850 standard specifies network redundancy which

improves the system availability for substation communication.

The network redundancy is based on two complementary

protocols defined in the IEC 62439-3 standard: PRP and HSR

protocols. Both the protocols are able to overcome a failure of a

link or switch with a zero switch-over time. In both the

protocols, each network node has two identical Ethernet ports

dedicated for one network connection. The protocols rely on

the duplication of all transmitted information and provide a zero

switch-over time if the links or switches fail, thus fulfilling all the

stringent real-time requirements of substation automation.

In PRP, each network node is attached to two independent

networks operated in parallel, thus providing zero time recovery

and continuous checking of redundancy to avoid failures. The

networks are completely separated to ensure failure

independence, and can have different topologies.

The relay can send binary and analog signals to other devices

using the IEC 61850-8-1 GOOSE (Generic Object Oriented

Substation Event) profile. Binary GOOSE messaging can be

employed, for example, for protection and interlocking-based

protection schemes. The relay meets the GOOSE performance

requirements for tripping applications in distribution

substations, as defined by the IEC 61850 standard (<10 ms

data exchange between the devices).

For redundant Ethernet communication, the relay offers two

galvanic Ethernet network interfaces. A third port with galvanic

Ethernet network interface is also available providing

connectivity for any other Ethernet device to an IEC 61850

station bus inside a switchgear bay, for example connection of

a remote I/O. Ethernet network redundancy can be achieved

using the high-availability seamless redundancy protocol (HSR)

or the parallel redundancy protocol (PRP) or with a self-healing

ring using Rapid Spanning Tree Protocol (RSTP) in managed

switches. Ethernet redundancy can be applied to Ethernet

based IEC 61850 and Modbus protocols.

Station communication

The 611 series protection relays support the IEC 61850 and

Modbus® communication protocols. Operational information

and controls are available through these protocols. However,

some communication functionality, for example, horizontal

communication between the protection relays, is enabled only

by the IEC 61850 communication protocol.

The IEC 61850 protocol is a core part of the relay as the

protection and control application is fully based on standard

modelling. The relay supports Edition 1 and Edition 2 versions

of the standard. With Edition 2 support, the relay has the latest

functionality modelling for substation applications and the best

interoperability for modern substations. It incorporates also full

support for standard device mode functionality supporting

different test applications. Control applications can utilize the

new safe and advanced station control authority feature.

The IEC 61850 communication implementation supports

monitoring and control functions. Additionally, parameter

settings, disturbance recordings and fault records can be

accessed using the IEC 61850 protocol. Disturbance

recordings are available to any Ethernet-based application in

the standard COMTRADE file format. The relay supports

simultaneous event reporting to five different clients on the

station bus. The relay can exchange data with other devices

using the IEC 61850 protocol.

Access control

To protect the relay from unauthorized access and to maintain

information integrity, the relay is provided with a four-level, role

based authentication system with administrator-programmable

individual passwords for the viewer, operator, engineer and

administrator levels. The access control applies to the local

HMI, the Web HMI and PCM600.

Inputs and outputs

The relay is equipped with three phase-segregated differential

current inputs and one residual current input. The differential

and the residual current inputs are rated 1/5 A, that is, the

inputs can be connected to either 1 A or 5 A secondary current

transformers. The optional residual current input rated 0.2/1 A

is normally used in applications requiring sensitive earth-fault

protection and featuring core-balance current transformers.

The rated currents of the analog inputs can be selected in the

relay software. In addition, the binary input threshold (16…176

V DC) can be selected by adjusting the relay’s parameter settings.

All binary input and output contacts are preconfigured

according to the configuration, but can be easily reconfigured

by setting application-based parameters using the signal

configuration functionality of the local HMI and Web HMI.

See the input and output overview table and the terminal

diagram for more information about the inputs and outputs.

Trip circuit supervision

The trip circuit supervision continuously monitors the availability

and operation of the trip circuit. It provides two open-circuit

monitoring functions that can be used to monitor the circuit

breaker’s control signal circuits. It also detects loss of circuit

breaker control voltage.

Self-supervision

The relay’s built-in self-supervision system continuously

monitors the state of the relay hardware and the operation of

the relay software. Any fault or malfunction detected is used for

alerting the operator.

A permanent relay fault blocks the protection functions to

prevent incorrect operation.

Recorded data

The relay has the capacity to store the records of the 128 latest

fault events. The records can be used to analyze the power

system events. Each record includes, for example, current,

residual voltage and angle values, start times of the protection

blocks and a time stamp. The fault recording can be triggered

by the start or the trip signal of a protection block, or by both.

The available measurement modes include DFT, RMS and

peak-to-peak. Fault records store relay measurement values at

the moment when any protection function starts. In addition,

the maximum demand current with time stamp is separately

recorded. The records are stored in the nonvolatile memory.

Trip circuit supervision

The trip circuit supervision continuously monitors the availability

and operation of the trip circuit. It provides two open-circuit

monitoring functions that can be used to monitor the circuit

breaker’s control signal circuits. It also detects loss of circuit

breaker control voltage.

Event log

To collect sequence-of-events information, the relay has a

nonvolatile memory capable of storing 1024 events with the

associated time stamps. The nonvolatile memory retains its

data even if the relay temporarily loses its auxiliary supply. The

event log facilitates detailed pre- and post-fault analyses of

feeder faults and disturbances. The considerable capacity to

process and store data and events in the relay facilitates

meeting the growing information demand of future network

configurations.

The sequence-of-events information can be accessed either via

local HMI or remotely via the communication interface of the

relay. The information can also be accessed locally or remotely

using the Web HMI.