MGC
Microgrid controller
The supervisory controller that dispatches sources, storage and loads and manages islanding and reconnection of a microgrid.
SLD / Schematic
Functional block · MTI
Microgrid transition-state indication
Functional block · Microgrids
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
What this block does
Reports that the controller is between its defined stable operating modes.
A simple example
In a microgrid serving a switchroom and industrial loads, the controller can move between grid-connected and islanded operating states only through its defined transition logic. Each state needs identifiable source roles and feedback. For this reference, the drawing identifies “Mode-transition logic” at the input and “Transition-in-progress indication” at the output. Intermediate states need explicit interpretation.
What the drawings help you do
Start at the named input: Mode-transition logic. Identify its source device or document and the state represented on the drawing. Follow the named output: Transition-in-progress indication. Cross-reference its destination and separate the command from confirmation that the equipment responded.
- Input
- Mode-transition logic
- Output
- Transition-in-progress indication
- Application reference
- An explanation of a named drawing function or circuit relationship; the project documents define the equipment and its connections.
Read the source: Microgrid operating modes and transitions management
Schematic · MTI
What it represents
Reports that the controller is between its defined stable operating modes. A microgrid operating-mode function coordinates how local sources and loads relate to the utility connection. The selected mode, the measured electrical condition and the actual switching configuration can differ during a transition.
In a microgrid serving a switchroom and industrial loads, the controller can move between grid-connected and islanded operating states only through its defined transition logic. Each state needs identifiable source roles and feedback. For this reference, the drawing identifies “Mode-transition logic” at the input and “Transition-in-progress indication” at the output. Intermediate states need explicit interpretation.
Show the requested mode, entry conditions, completion feedback and failure indication. These functional blocks explain control responsibilities and do not specify a ready-to-use operating sequence or grid-connection approval. 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.
How to read it
- Start at the named input: Mode-transition logic. Identify its source device or document and the state represented on the drawing.
- Follow the named output: Transition-in-progress indication. Cross-reference its destination and separate the command from confirmation that the equipment responded.
- Intermediate states need explicit interpretation.
- Show the requested mode, entry conditions, completion feedback and failure indication. These functional blocks explain control responsibilities and do not specify a ready-to-use operating sequence or grid-connection approval.
Information to show or reference
- Label the source and connection reference for mode-transition logic.
- Identify the destination and defined state of transition-in-progress indication.
- Record the equipment or control-document revision supporting this functional block.
- Check this application limit in the project design: Intermediate states need explicit interpretation.
A distinction that matters
Intermediate states need explicit interpretation. 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.
Sources you can follow
These public references support the explanation and provide further detail. Their graphics and downloadable files remain with their publishers.
Microgrid operating modes and transitions management
Public technical context for microgrid operating-mode controls. Grid-connected and island modes, transitions, topology and authority. The application text and educational graphic are independently authored; the publisher does not certify this representation.
About this graphic
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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