Functional block diagram of the S24/U relay
General presentation
The S24/U relay is a multifunction digital protection relay mainly used for voltage and frequency monitoring on transmission, distribution, industrial or commercial networks. It consists of a three-phase voltage unit and a 4th input dedicated to the synchrocheck function.
It belongs to the S24 family, part of the SMARTLINE range. These devices offer a wide set of functions in a compact housing. Among other uses, they are particularly suited to the LV compartments of MV switchgear cubicles.
The particularity of these relays is that, although they belong to the SMARTLINE range, their hardware and firmware are the same as those of the relays making up the PROTECTA range. They therefore share the same physical and electrical characteristics. This provides extensive field experience of their use and operation, as well as consistent and optimum manufacturing lead times. The main difference between the two ranges is the housing.
The EuroCAP configuration tool, available free of charge, provides a user-friendly and flexible application for protection, control and measurement functions, ensuring that the protection devices are fully customisable.
General features
- Native IEC 61850, Edition 2 compatible
- Standard 144 × 144 mm housing
- The predefined factory configuration can be customised to the user’s specifications with the EuroCAP tool
- Various types of HMI:
- Colour touch screen
- Monochrome (B&W) alphanumeric display with 4 touch buttons.
- Built-in web server as well as extended measurement, control and monitoring functions.
- User-configurable LCD displays for the colour touch HMI, able to show single line diagrams with position indication and control of the switching devices, as well as measurement values of the controllable objects
- Adaptive protection
- Circuit breaker monitoring and control
- High-capacity disturbance recorder (DRE) and event logging:
- DRE supporting up to 32 analogue signal channels and 64 digital signal channels
- The event recorder can store more than 10,000 events
- Various mounting types:
- Flush-mounted;
- Semi-flush-mounted;
- DIN rail
- Numerous communication protocols:
- Ethernet communication: IEC 61850; IEC 60870-5-104; DNP3.0 TCP; Modbus TCP
- Serial communication: DNP3.0; IEC 60870-5-101/103; MODBUS, SPA
- Legacy network protocols over 100Base-FX and 10/100Base-TX (RJ45)
- Optional communication ports:
- Ethernet over optical fibre (MM/ST, SM/FC),
- RJ45,
- POF serial,
- Serial over optical fibre,
- RS-485/422
- Simultaneous support of several communication protocols
- Built-in self-monitoring function (hardware and software) – Watchdog
- Various time sources available:
- NTP server;
- IRIG B
Applications
The S24/U relay is a multifunction digital voltage relay. Its full set of functionalities allows it to be used on an incomer or a feeder (line or cable) or on a busbar. The voltage- and frequency-based functions make this intelligent electronic device (IED) well suited to the protection and control of these quantities.
This protection includes various versatile functions based on both current and voltage measurement, such as overvoltage and undervoltage protection, frequency variations, residual voltage and source transfer (synchrocheck).
This relay also integrates a wide range of control and supervision functions, providing full control and user-defined interlocking schemes for the substation switchgear.
Protection and control functions
- Synchronism check – synchrocheck function – dead line detection
- Definite time undervoltage protection
- Definite time overvoltage protection
- Definite time residual overvoltage protection (calculated from the phase voltages)
- Voltage transformer supervision
- Overfrequency protection
- Underfrequency protection
- Rate of change of frequency protection
The S24/U voltage relay for the decoupling protection function
The S24/U, holder of the ATE 26B006 approval, is the relay in its native configuration, without any prior settings linked to a particular application. This is the version to choose when you wish to define all thresholds and functions yourself according to your own specification, or when the intended use does not correspond to a decoupling protection. You keep complete freedom of configuration, but all the settings – including, where applicable, compliance with a grid code – remain your responsibility. This version is supplied without a sealable cover: if you need one, it must be ordered separately.
The S24/U is our reference voltage relay. It comes in three versions of the relay alone, plus a complete cabinet solution. These solutions differ not in their basic electronics, but in the level of configuration, settings and mechanical integration carried out before they reach you. This choice has a direct impact on the on-site integration time and on how compliance responsibilities are shared. For an overview, see the page: Choosing your decoupling protection
General documentation : Smartline S24 DataSheet – 19AA1121500B
Operation manual : S24U OMA 23AA3411548
Click on the link to access the technical documentation to attach to your order : DOCACOM_S24
