Numerical protection relay (IED)
Single relay block on an SLD that lists the protection functions it provides, with CT, VT and trip connections.
An independently authored application reference. The drawing shows the named function or circuit relationship; use the project legend and selected equipment documentation for its drafting form and connections.
Browse this installation focusIn plain English
Publishes the assigned sampled voltage quantities from the selected measurement interface.
In a digital substation bay, a merging unit digitizes local measurements and a protective relay subscribes to the assigned data stream. The command return path and communication-health indications are drawn separately. For this reference, the drawing identifies “Local voltage measurements” at the input and “Published sampled voltage stream” at the output. Voltage reference and phase identity must be retained.
Start at the named input: Local voltage measurements. Identify its source device or document and the state represented on the drawing. Follow the named output: Published sampled voltage stream. Cross-reference its destination and separate the command from confirmation that the equipment responded.
Read the source: Digital secondary systems: Sampled Values
Publishes the assigned sampled voltage quantities from the selected measurement interface. Digital substation interfaces carry measurements, status and control information between primary equipment and protective devices. Measurement streams, event messages and time synchronization are separate dependencies even when they share an Ethernet network.
In a digital substation bay, a merging unit digitizes local measurements and a protective relay subscribes to the assigned data stream. The command return path and communication-health indications are drawn separately. For this reference, the drawing identifies “Local voltage measurements” at the input and “Published sampled voltage stream” at the output. Voltage reference and phase identity must be retained.
Identify publisher, subscriber, data meaning and quality handling. Protocol labels alone do not establish protection performance, compatibility or network redundancy; these need the selected system configuration and validation. The functional block is an independent explanation of this named application. Equipment-specific ratings, terminal connections and operating conditions must be established in the project documentation.
Voltage reference and phase identity must be retained. This reference describes the named application; it does not establish a new IEC graphical symbol, an ANSI device-function number or an exact manufacturer connection diagram.
These public references support the explanation and provide further detail. Their graphics and downloadable files remain with their publishers.
Public technical context for digital substation process interfaces. Merging units, sampled measurements, GOOSE, process bus and network redundancy. The application text and educational graphic are independently authored; the publisher does not certify this representation.
This illustration was authored independently by Elora Grid to explain the concept. It is not reproduced from a customer drawing, an official standard graphic or a manufacturer CAD file. Its correspondence to an exact IEC or IEEE symbol identifier has not been certified.
SVG and DXF downloads contain this original artwork. Original artwork is available under CC BY 4.0. Third-party references retain their own terms.
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