# Microgrid operating-mode history recorder

Canonical URL: https://eloragrid.ai/symbols/microgrid-operating-mode-history-recorder
Publisher: Elora Grid
Updated: 2026-11-03
Lookup label: MOHR
Drawing use: Schematic
Reference families: Manufacturer

Representation: Functional block
Installation focus: microgrids
Input: Mode events and causes
Output: Operating-mode history

Associates confirmed mode changes with their initiating cause and recorded time.

## In plain English

### What this block does

Associates confirmed mode changes with their initiating cause and recorded time.

### 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 events and causes” at the input and “Operating-mode history” at the output. Clock quality affects event interpretation.

### What the drawings help you do

Start at the named input: Mode events and causes. Identify its source device or document and the state represented on the drawing. Follow the named output: Operating-mode history. Cross-reference its destination and separate the command from confirmation that the equipment responded.

### Terms

- Input: Mode events and causes
- Output: Operating-mode history
- Application reference: An explanation of a named drawing function or circuit relationship; the project documents define the equipment and its connections.

Concept diagram: Mode events and causes → MOHR → Operating-mode history
A reading guide. The entry's original illustration and input/output facts describe this application.

- [Microgrid operating modes and transitions management](https://productinfo.se.com/emol_functional_specifications/doca0371_emol_functionalspecifications/EN/DOCA0371_EMOL_Functional_Specifications_DD00894746.xml/%24/EMOL_OperatingModesandTransitionsManagement_DD00895904)


## What it represents

Associates confirmed mode changes with their initiating cause and recorded time. 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 events and causes” at the input and “Operating-mode history” at the output. Clock quality affects event 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 events and causes. Identify its source device or document and the state represented on the drawing.
- Follow the named output: Operating-mode history. Cross-reference its destination and separate the command from confirmation that the equipment responded.
- Clock quality affects event 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 events and causes.
- Identify the destination and defined state of operating-mode history.
- Record the equipment or control-document revision supporting this functional block.
- Check this application limit in the project design: Clock quality affects event interpretation.

## Important distinction

Clock quality affects event 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.

## Facts

- Representation: Functional block
- Installation focus: Microgrids
- Input / boundary: Mode events and causes
- Output / connection: Operating-mode history
- Lookup label: MOHR is a library lookup label, not a standard device designation.

## Public references

- [Microgrid operating modes and transitions management](https://productinfo.se.com/emol_functional_specifications/doca0371_emol_functionalspecifications/EN/DOCA0371_EMOL_Functional_Specifications_DD00894746.xml/%24/EMOL_OperatingModesandTransitionsManagement_DD00895904) — Schneider Electric. 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.

## Graphic scope

Independent original educational concept illustration by Elora Grid. Not a certified standards graphic or manufacturer footprint. Unitless; not to scale. Original artwork licence: https://creativecommons.org/licenses/by/4.0/. Publisher material is linked only.