{"schemaVersion":1,"slug":"ct-secondary-protection-zone-crossover","name":"CT secondary protection-zone crossover","kind":"symbol","abbreviation":"CSPC","aliases":["Current-transformer secondary arrangements","substations Current-transformer secondary arrangements","substations","Substations","Adjacent CT locations","Protection-zone overlap reference"],"category":"measurement-protection","drawingTypes":["Schematic"],"referenceFamilies":["Manufacturer"],"summary":"Identifies a current-measurement interface that affects the overlap between neighboring protection zones.","description":["Identifies a current-measurement interface that affects the overlap between neighboring protection zones. A current-transformer secondary arrangement carries a measuring current from a defined primary location to metering or protection inputs. Core identity, polarity and the connected circuit determine the measurement's meaning.","In a substation protection panel, separate CT cores can supply metering and protection circuits with different duties. A test boundary must preserve the secondary arrangement required by the selected CT and test device. For this reference, the drawing identifies “Adjacent CT locations” at the input and “Protection-zone overlap reference” at the output. Physical equipment boundaries can differ from protection zones.","Trace every secondary connection and the assigned earthing point against the actual connection diagram. These illustrations explain circuit roles and never prescribe a live CT switching or disconnection procedure. 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."],"readingNotes":["Start at the named input: Adjacent CT locations. Identify its source device or document and the state represented on the drawing.","Follow the named output: Protection-zone overlap reference. Cross-reference its destination and separate the command from confirmation that the equipment responded.","Physical equipment boundaries can differ from protection zones.","Trace every secondary connection and the assigned earthing point against the actual connection diagram. These illustrations explain circuit roles and never prescribe a live CT switching or disconnection procedure."],"drawingChecklist":["Label the source and connection reference for adjacent ct locations.","Identify the destination and defined state of protection-zone overlap reference.","Record the equipment or control-document revision supporting this functional block.","Check this application limit in the project design: Physical equipment boundaries can differ from protection zones."],"distinction":"Physical equipment boundaries can differ from protection zones. 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":[{"label":"Representation","value":"Functional block"},{"label":"Installation focus","value":"Substations"},{"label":"Input / boundary","value":"Adjacent CT locations"},{"label":"Output / connection","value":"Protection-zone overlap reference"},{"label":"Lookup label","value":"CSPC is a library lookup label, not a standard device designation."}],"references":[{"sourceId":"instrument-transformers","relevance":"Public technical context for current-transformer secondary arrangements. Current and voltage measurement transformers and their secondary interfaces. The application text and educational graphic are independently authored; the publisher does not certify this representation."}],"related":["current-transformer","ct-test-terminal","ct-multi-ratio-tap-selection-reference"],"artwork":"pi26-ct-secondary-protection-zone-crossover","publishedOn":"2026-11-03","updatedOn":"2026-11-03","provenance":"independent-public-research","representation":{"type":"functional-block","focus":"substations","family":"ct-secondary","input":"Adjacent CT locations","output":"Protection-zone overlap reference"},"plainEnglish":{"title":"What this block does","introduction":"Identifies a current-measurement interface that affects the overlap between neighboring protection zones.","example":"In a substation protection panel, separate CT cores can supply metering and protection circuits with different duties. A test boundary must preserve the secondary arrangement required by the selected CT and test device. For this reference, the drawing identifies “Adjacent CT locations” at the input and “Protection-zone overlap reference” at the output. Physical equipment boundaries can differ from protection zones.","drawings":"Start at the named input: Adjacent CT locations. Identify its source device or document and the state represented on the drawing. Follow the named output: Protection-zone overlap reference. Cross-reference its destination and separate the command from confirmation that the equipment responded.","terms":[{"name":"Input","meaning":"Adjacent CT locations"},{"name":"Output","meaning":"Protection-zone overlap reference"},{"name":"Application reference","meaning":"An explanation of a named drawing function or circuit relationship; the project documents define the equipment and its connections."}],"diagram":"flow","steps":["Adjacent CT locations","CSPC","Protection-zone overlap reference"],"caption":"A reading guide. The entry's original illustration and input/output facts describe this application.","sources":[{"label":"Indoor current and voltage transformers","url":"https://www.abb.com/gb/en/areas/electrification/medium-voltage/grid-components/core-components/indoor-instrument-transformers"}],"profileId":"power-installation-ct-secondary"},"url":"https://eloragrid.ai/symbols/ct-secondary-protection-zone-crossover","illustration":{"url":"https://eloragrid.ai/tools/electrical-library/illustrations/ct-secondary-protection-zone-crossover.svg","scope":"Original educational concept; not an official standard graphic or product footprint","license":"https://creativecommons.org/licenses/by/4.0/"},"sources":[{"id":"instrument-transformers","title":"Indoor current and voltage transformers","publisher":"ABB","url":"https://www.abb.com/gb/en/areas/electrification/medium-voltage/grid-components/core-components/indoor-instrument-transformers","type":"manufacturer","scope":"Public current- and voltage-transformer product families. Ratings, terminals and dimensions depend on the model.","checkedOn":"2026-10-13","reuse":"link-only","relevance":"Public technical context for current-transformer secondary arrangements. Current and voltage measurement transformers and their secondary interfaces. The application text and educational graphic are independently authored; the publisher does not certify this representation."}]}