# Single-breaker bus-coupler arrangement Canonical URL: https://eloragrid.ai/symbols/single-breaker-bus-coupler-arrangement Publisher: Elora Grid Updated: 2026-11-03 Lookup label: SBA Drawing use: SLD, Schematic Reference families: Manufacturer Representation: Circuit arrangement Installation focus: switchyards Input: Two bus sections Output: Coupler connection Connects the assigned bus sections through their defined coupler breaker path. ## In plain English ### What this arrangement shows Connects the assigned bus sections through their defined coupler breaker path. ### A simple example In a switchyard, a single-line arrangement helps identify the bay connections, tie devices and possible alternate supply paths. Normal open points must remain separate from the equipment's physical ability to close. For this reference, the drawing identifies “Two bus sections” at the input and “Coupler connection” at the output. A coupler is distinct from an outgoing circuit breaker. ### What the drawings help you do Start at the named input: Two bus sections. Identify its source device or document and the state represented on the drawing. Follow the named output: Coupler connection. Cross-reference its destination and separate the command from confirmation that the equipment responded. ### Terms - Input: Two bus sections - Output: Coupler connection - Application reference: An explanation of a named drawing function or circuit relationship; the project documents define the equipment and its connections. Concept diagram: Two bus sections → SBA → Coupler connection A reading guide. The entry's original illustration and input/output facts describe this application. - [SEL-451 protection, automation and bay control](https://selinc.com/products/451/) ## What it represents Connects the assigned bus sections through their defined coupler breaker path. A busbar arrangement defines the available paths between incoming circuits, outgoing circuits and bus sections. Its switching devices and measurement boundaries determine how a circuit can remain connected when part of the installation is unavailable. In a switchyard, a single-line arrangement helps identify the bay connections, tie devices and possible alternate supply paths. Normal open points must remain separate from the equipment's physical ability to close. For this reference, the drawing identifies “Two bus sections” at the input and “Coupler connection” at the output. A coupler is distinct from an outgoing circuit breaker. Name each bus, bay and switching device. The arrangement illustrates electrical connectivity; reliability, fault levels, permitted switching and protection coordination require the actual network design. The circuit arrangement 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: Two bus sections. Identify its source device or document and the state represented on the drawing. - Follow the named output: Coupler connection. Cross-reference its destination and separate the command from confirmation that the equipment responded. - A coupler is distinct from an outgoing circuit breaker. - Name each bus, bay and switching device. The arrangement illustrates electrical connectivity; reliability, fault levels, permitted switching and protection coordination require the actual network design. ## Information to show or reference - Label the source and connection reference for two bus sections. - Identify the destination and defined state of coupler connection. - Record the equipment or control-document revision supporting this circuit arrangement. - Check this application limit in the project design: A coupler is distinct from an outgoing circuit breaker. ## Important distinction A coupler is distinct from an outgoing circuit breaker. 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: Circuit arrangement - Installation focus: Switchyards - Input / boundary: Two bus sections - Output / connection: Coupler connection - Lookup label: SBA is a library lookup label, not a standard device designation. ## Public references - [SEL-451 protection, automation and bay control](https://selinc.com/products/451/) — SEL. Public technical context for switchyard busbar arrangements. Bus arrangements, breaker control and bay-level coordination. 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.