# Breaker double-point status decoding

Canonical URL: https://eloragrid.ai/symbols/breaker-double-point-status-decoding
Publisher: Elora Grid
Updated: 2026-11-03
Lookup label: BDSD
Drawing use: Schematic
Reference families: Manufacturer

Representation: Functional block
Installation focus: switchgear
Input: 52a and 52b states
Output: Decoded breaker position

Interprets the two independent auxiliary indications as open, closed or an invalid combination.

## In plain English

### What this block does

Interprets the two independent auxiliary indications as open, closed or an invalid combination.

### A simple example

In a switchgear control schematic, the bay controller compares independent status contacts before displaying a position or allowing another operation. The signal labels explain which physical state each contact represents. For this reference, the drawing identifies “52a and 52b states” at the input and “Decoded breaker position” at the output. Disagreement must remain distinguishable from transition.

### What the drawings help you do

Start at the named input: 52a and 52b states. Identify its source device or document and the state represented on the drawing. Follow the named output: Decoded breaker position. Cross-reference its destination and separate the command from confirmation that the equipment responded.

### Terms

- Input: 52a and 52b states
- Output: Decoded breaker position
- Application reference: An explanation of a named drawing function or circuit relationship; the project documents define the equipment and its connections.

Concept diagram: 52a and 52b states → BDSD → Decoded breaker position
A reading guide. The entry's original illustration and input/output facts describe this application.

- [Masterclad medium-voltage switchgear: circuit-breaker section interlocks](https://productinfo.se.com/masterclad_mv_switchgear_ib/6055-30-masterclad-15kv-mv-switchgear-ib/English/6055-30%20Masterclad%20MV%20Switchgear%20Indoor%20%28bookmap%29_DD00646805.xml/%24/Section6-CircuitBreakerSectionInter-58DD6EC7)


## What it represents

Interprets the two independent auxiliary indications as open, closed or an invalid combination. Breaker status indications describe the operating mechanism, the removable truck or the health of a supporting system. These signals are related but are not interchangeable: an open breaker can still have its truck connected to live bus contacts.
In a switchgear control schematic, the bay controller compares independent status contacts before displaying a position or allowing another operation. The signal labels explain which physical state each contact represents. For this reference, the drawing identifies “52a and 52b states” at the input and “Decoded breaker position” at the output. Disagreement must remain distinguishable from transition.
Keep contact reference conditions, terminal numbers and interpretation logic together. Distinguish a mechanically operated indication from a measured current or voltage condition. 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: 52a and 52b states. Identify its source device or document and the state represented on the drawing.
- Follow the named output: Decoded breaker position. Cross-reference its destination and separate the command from confirmation that the equipment responded.
- Disagreement must remain distinguishable from transition.
- Keep contact reference conditions, terminal numbers and interpretation logic together. Distinguish a mechanically operated indication from a measured current or voltage condition.

## Information to show or reference

- Label the source and connection reference for 52a and 52b states.
- Identify the destination and defined state of decoded breaker position.
- Record the equipment or control-document revision supporting this functional block.
- Check this application limit in the project design: Disagreement must remain distinguishable from transition.

## Important distinction

Disagreement must remain distinguishable from transition. 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: Switchgear
- Input / boundary: 52a and 52b states
- Output / connection: Decoded breaker position
- Lookup label: BDSD is a library lookup label, not a standard device designation.

## Public references

- [Masterclad medium-voltage switchgear: circuit-breaker section interlocks](https://productinfo.se.com/masterclad_mv_switchgear_ib/6055-30-masterclad-15kv-mv-switchgear-ib/English/6055-30%20Masterclad%20MV%20Switchgear%20Indoor%20%28bookmap%29_DD00646805.xml/%24/Section6-CircuitBreakerSectionInter-58DD6EC7) — Schneider Electric. Public technical context for breaker position and status interfaces. Breaker control, mechanism, position contacts, racking interlocks and test interfaces. 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.