The S24 Variant 4 is used mostly as the main or backup protection of overhead lines or cable networks. The main protection function of this configuration is the line differential protection. It is a member of the S24 series, which is part of the EuroProt+ Smart Line. Members of the Smart Line also offer a wide range of functions but they do so in a small, compact enclosure so that they can be installed in locations with limited space available for the protection equipment.
The S24 series contain special selections of the EuroProt+ modules and functions, composed with cost effectiveness in mind. Depending on the standard configuration chosen (Variant 1, Variant2,…), the IED is adapted to the protection of medium-voltage feeders in isolated neutral, resistance earthed, compensated and solidly earthed networks. Once the application-specific settings have been defined for the standard configuration IED, it can be put into service directly. Areas of application include protection functions for a large variety of applications, e.g. transformer differential and restricted earth fault protection, frequency and voltage based protection, motor protection, thermal overload protection.
The EuroCAP configuration tool, which is available free of charge, offers a user-friendly and flexible application for protection, control and measurement functions to ensure that the IED-EP+ S24 devices are fully customizable.
General features
Native IEC 61850 IED with Edition 2 compatibility
Standard module layouts with options
24 HP wide rack size (height: 3U)
The pre-defined factory configuration can be customized to the user’s specification with the powerful EuroCAP tool
Different HMI types: advanced HMI with color touchscreen and black-and-white display with 4 tactile push buttons. An embedded web server and extended measuring, control and monitoring functions are also available for both types
User configurable LCD user screens for the HMI-type color touchscreen, which can display SLDs (Single Line Diagrams) with switchgear position indication and control as well as measuring values and several types of controllable objects
Various protection setting groups
Enhanced breaker monitoring and control
High capacity disturbance recorder (DRE) and event logging:
DRE for up to 32 analogue and 64 digital signal channels
Event recorder can store more than 10,000 events
Mounting methods: Flush mounting; Semi-flush mounting; Din rail mounting
Serial communication: DNP3.0; IEC60870-5-101/103; MODBUS, SPA
Legacy network based protocols via 100Base-FX and 10/100Base-TX (RJ45)
Optional communication ports: Fiber optical Ethernet (MM/ST, SM/FC), RJ45, Serial POF, Serial glass fiber, RS-485/422
Handling of several communication protocols simultaneously
Built-in self-monitoring to detect internal hardware or software errors
Different time sources available: NTP server; Minute pulse; Legacy protocol master
Application
Variant 4 is used mostly as the main or backup protection of overhead lines or cable networks. It is a member of the S24 series, which is part of the EuroProt+ Smart Line.
The main protection function of the Variant 4 configuration is the line differential protection. The communication hardware module sends and receives phase current vectors to realize this function. Additionally, the Variant 4 relay includes a variety of versatile feeder protection functions such as three-phase, residual and negative sequence overcurrent protection, thermal overload protection, etc. It can be used as a back-up protection relay for downstream equipment (e.g. feeders, cables). The automatic reclosing function is also part of the standard configuration.
The IED includes a wide range of control and supervisory functions, which provide full control and user-defined interlocking schemes for the primary switchgear at the substation.
SCOPE OF APPLICATION
Line differential protection function
Length of the protected line up to 50km with single-mode fiber optic cable; short lines up to 1 km with mono-mode fiber optic cable port are also supported
Three-phase, residual and negative sequence overcurrent, thermal overload protection functions
The implemented protection functions provide back-up protection for downstream equipment (e.g. feeders, cables etc.)
Automatic reclosing function
Breaker failure protection function
Inrush detection
Current unbalance detection of CT’s
Programmable interlocking schemes
Protection & control functions
The Variant 4 configuration measures the three phase currents and the residual current. The main protection function in this application is the line differential protection function. Additionally, overcurrent functions and the thermal overload function are also available for protection of overhead lines and cable networks. The configuration is designed to meet the protection requirements of a medium-voltage field unit.
Protection & control functions
IEC
ANSI
*Inst.
Negative sequence overcurrent protection function
I2>
46
1
04/04/2025
Broken conductor protection
I2/I1>
46BC
1
30/06/2020
Line thermal protection function
T >
49
1
03/01/2025
Three-phase instantaneous overcurrent protection function
I >>>
50
1
17/01/2025
Residual instantaneous overcurrent protection function
Io>>>
50N/50G
1
09/12/2025
Breaker failure protection functions
CBFP
50BF
1
03/10/2022
Three-phase time overcurrent protection function
I>, I>>
51
2
04/04/2025
Residual overcurrent protection function
Io>, Io>>
51N/51G
2
04/04/2025
Current unbalance function (CT Supervision)
60
1
20/12/2024
Inrush current detection function
I2h>
68
1
20/12/2024
Automatic reclosing function for medium voltage networks
0 -> 1
79
1
10/12/2024
Line differential protection function
3IdL >
87L
1
06/01/2025
*The INST. column contains the numbers of the pre-configured function blocks in the factory configuration.These numbers may be different in order to meet the user’s requirements.
Documentation
Product Configuration Options
Brochures
EuroProt+ overview
19/02/2021
System Description
IED-EP+ S24 general specification
19/02/2021
Hardware Guides
Maintenance guide
28/06/2023
Hardware description
31/07/2026
Application Guides
Line differential communication application guide
31/08/2023
IEC61850 documents
TISSUEs Implementation Conformance Statement (TICS) for the IEC 61850 Edition 2 server interface in Europrot+ product family
18/04/2023
Protocol Implementation eXtra Information for Testing (PIXIT) for the IEC 61850 Edition 2 server interface in Europrot+ product family
18/04/2023
Protocol Implementation Conformance Statement (PICS) for the IEC 61850 Edition 2 server interface in Europrot+ product family
18/04/2023
Protocol Implementation eXtra Information for Testing (PIXIT) for the IEC 61850 Edition 1 server interface in Europrot+ product family
09/07/2019
Protocol Implementation Conformance Statement (PICS) for the IEC 61850 Edition 1 server interface in Eurorot+ product family
09/07/2019
Model Implementation Conformance Statement (MICS) for the IEC 61850 Edition 1 server interface in the Eurorot+ product family
09/07/2019
Configuration Descriptions
Variant 4 configuration description
30/05/2023
Variant 4 product configuration options
27/07/2026
Order
Protecta products can be ordered by using an Order Code. This code specifies the hardware and the configuration. Please always refer to a valid Order Code when placing an order. The Order Code page can be opened by clicking the link below.
Protecta provides own‑developed protection, automation & control devices for power generation, transmission, distribution, industrial and renewable energy (microgrid) applications.
Késmárk u. 7/A, 1158 Budapest, Hungary+36 1 415 3800protecta@protecta.huProtecta LinkedIn