# Double-bus single-breaker bay arrangement Canonical URL: https://eloragrid.ai/symbols/double-bus-single-breaker-bay-arrangement Publisher: Elora Grid Updated: 2026-11-03 Lookup label: DSBA Drawing use: SLD, Schematic Reference families: Manufacturer Representation: Circuit arrangement Installation focus: switchyards Input: Two bus choices Output: Selected bay bus connection Provides the assigned bay with selected connection paths to two buses through one circuit breaker. ## In plain English ### What this arrangement shows Provides the assigned bay with selected connection paths to two buses through one circuit breaker. ### 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 choices” at the input and “Selected bay bus connection” at the output. Bus selection depends on the disconnector arrangement. ### What the drawings help you do Start at the named input: Two bus choices. Identify its source device or document and the state represented on the drawing. Follow the named output: Selected bay bus connection. Cross-reference its destination and separate the command from confirmation that the equipment responded. ### Terms - Input: Two bus choices - Output: Selected bay bus 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 choices → DSBA → Selected bay bus 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 Provides the assigned bay with selected connection paths to two buses through one circuit breaker. 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 choices” at the input and “Selected bay bus connection” at the output. Bus selection depends on the disconnector arrangement. 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 choices. Identify its source device or document and the state represented on the drawing. - Follow the named output: Selected bay bus connection. Cross-reference its destination and separate the command from confirmation that the equipment responded. - Bus selection depends on the disconnector arrangement. - 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 choices. - Identify the destination and defined state of selected bay bus connection. - Record the equipment or control-document revision supporting this circuit arrangement. - Check this application limit in the project design: Bus selection depends on the disconnector arrangement. ## Important distinction Bus selection depends on the disconnector arrangement. 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 choices - Output / connection: Selected bay bus connection - Lookup label: DSBA 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.