{"schemaVersion":1,"slug":"station-utc-local-display-boundary","name":"Station UTC-local display boundary","kind":"symbol","abbreviation":"SUDB","aliases":["Substation timing and event interfaces","substations Substation timing and event interfaces","substations","Substations","Recorded UTC time","Local display time"],"category":"measurement-protection","drawingTypes":["Schematic"],"referenceFamilies":["Manufacturer"],"summary":"Separates the common recorded time basis from an operator's displayed local time.","description":["Separates the common recorded time basis from an operator's displayed local time. A station time system provides a shared time reference for protection records, measurements and automation. Different devices can use different timing protocols, so the time source, distribution path and quality information must remain identifiable.","In a substation, a station clock can provide precision timing to process equipment and another timing interface to event recorders. The alarm system should distinguish loss of a distribution path from loss of the external time source. For this reference, the drawing identifies “Recorded UTC time” at the input and “Local display time” at the output. Daylight-saving display changes must not alter event identity.","Show the source and client of each time connection. Required accuracy, holdover, protocol profile and loss-of-time behavior follow the selected application; a common timestamp format does not guarantee synchronized events. 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: Recorded UTC time. Identify its source device or document and the state represented on the drawing.","Follow the named output: Local display time. Cross-reference its destination and separate the command from confirmation that the equipment responded.","Daylight-saving display changes must not alter event identity.","Show the source and client of each time connection. Required accuracy, holdover, protocol profile and loss-of-time behavior follow the selected application; a common timestamp format does not guarantee synchronized events."],"drawingChecklist":["Label the source and connection reference for recorded utc time.","Identify the destination and defined state of local display time.","Record the equipment or control-document revision supporting this functional block.","Check this application limit in the project design: Daylight-saving display changes must not alter event identity."],"distinction":"Daylight-saving display changes must not alter event identity. 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":"Recorded UTC time"},{"label":"Output / connection","value":"Local display time"},{"label":"Lookup label","value":"SUDB is a library lookup label, not a standard device designation."}],"references":[{"sourceId":"pi26-station-time","relevance":"Public technical context for substation timing and event interfaces. PTP, NTP, IRIG-B, pulse distribution, reference failover and timing quality. The application text and educational graphic are independently authored; the publisher does not certify this representation."}],"related":["sequence-of-events-recorder","phasor-measurement-unit","time-distribution-redundant-path-interface"],"artwork":"pi26-station-utc-local-display-boundary","publishedOn":"2026-11-03","updatedOn":"2026-11-03","provenance":"independent-public-research","representation":{"type":"functional-block","focus":"substations","family":"station-time","input":"Recorded UTC time","output":"Local display time"},"plainEnglish":{"title":"What this block does","introduction":"Separates the common recorded time basis from an operator's displayed local time.","example":"In a substation, a station clock can provide precision timing to process equipment and another timing interface to event recorders. The alarm system should distinguish loss of a distribution path from loss of the external time source. For this reference, the drawing identifies “Recorded UTC time” at the input and “Local display time” at the output. Daylight-saving display changes must not alter event identity.","drawings":"Start at the named input: Recorded UTC time. Identify its source device or document and the state represented on the drawing. Follow the named output: Local display time. Cross-reference its destination and separate the command from confirmation that the equipment responded.","terms":[{"name":"Input","meaning":"Recorded UTC time"},{"name":"Output","meaning":"Local display time"},{"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":["Recorded UTC time","SUDB","Local display time"],"caption":"A reading guide. The entry's original illustration and input/output facts describe this application.","sources":[{"label":"SEL-2488 satellite-synchronised network clock","url":"https://selinc.com/products/2488/"}],"profileId":"power-installation-station-time"},"url":"https://eloragrid.ai/symbols/station-utc-local-display-boundary","illustration":{"url":"https://eloragrid.ai/tools/electrical-library/illustrations/station-utc-local-display-boundary.svg","scope":"Original educational concept; not an official standard graphic or product footprint","license":"https://creativecommons.org/licenses/by/4.0/"},"sources":[{"id":"pi26-station-time","publisher":"SEL","title":"SEL-2488 satellite-synchronised network clock","url":"https://selinc.com/products/2488/","scope":"PTP, NTP, IRIG-B, pulse distribution, reference failover and timing quality.","type":"manufacturer","checkedOn":"2026-11-03","reuse":"link-only","relevance":"Public technical context for substation timing and event interfaces. PTP, NTP, IRIG-B, pulse distribution, reference failover and timing quality. The application text and educational graphic are independently authored; the publisher does not certify this representation."}]}