{"schemaVersion":1,"slug":"switchroom-humidity-high-alarm","name":"Switchroom humidity high alarm","kind":"symbol","abbreviation":"SHHA","aliases":["Switchroom environmental supervision","switchrooms Switchroom environmental supervision","switchrooms","Switchrooms","Room humidity measurement","High-humidity indication"],"category":"installation-communications","drawingTypes":["Schematic"],"referenceFamilies":["Manufacturer"],"summary":"Reports humidity exceeding the defined supervision condition at the monitored location.","description":["Reports humidity exceeding the defined supervision condition at the monitored location. Environmental supervision turns measurements or contact states into clearly named room-service indications. A sensor measures a condition; the supervisory function decides whether the assigned alarm or control response is needed.","In a switchroom, water ingress, temperature, humidity and equipment-service alarms can be sent to the station controller with separate point names so an operator can identify the affected area. For this reference, the drawing identifies “Room humidity measurement” at the input and “High-humidity indication” at the output. Relative humidity varies with temperature.","Keep sensor location, alarm thresholds, delay and monitoring coverage in the room-services schedule. An environmental alarm is a diagnostic input, not a complete assessment of electrical equipment 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."],"readingNotes":["Start at the named input: Room humidity measurement. Identify its source device or document and the state represented on the drawing.","Follow the named output: High-humidity indication. Cross-reference its destination and separate the command from confirmation that the equipment responded.","Relative humidity varies with temperature.","Keep sensor location, alarm thresholds, delay and monitoring coverage in the room-services schedule. An environmental alarm is a diagnostic input, not a complete assessment of electrical equipment condition."],"drawingChecklist":["Label the source and connection reference for room humidity measurement.","Identify the destination and defined state of high-humidity indication.","Record the equipment or control-document revision supporting this functional block.","Check this application limit in the project design: Relative humidity varies with temperature."],"distinction":"Relative humidity varies with temperature. 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":"Switchrooms"},{"label":"Input / boundary","value":"Room humidity measurement"},{"label":"Output / connection","value":"High-humidity indication"},{"label":"Lookup label","value":"SHHA is a library lookup label, not a standard device designation."}],"references":[{"sourceId":"pi26-ventilation","relevance":"Public technical context for switchroom environmental supervision. Heat removal, condensation and environmental design context. The application text and educational graphic are independently authored; the publisher does not certify this representation."}],"related":["relative-humidity-sensor","temperature-indicator","switchroom-environmental-sensor-fault-alarm"],"artwork":"pi26-switchroom-humidity-high-alarm","publishedOn":"2026-11-03","updatedOn":"2026-11-03","provenance":"independent-public-research","representation":{"type":"functional-block","focus":"switchrooms","family":"room-environment","input":"Room humidity measurement","output":"High-humidity indication"},"plainEnglish":{"title":"What this block does","introduction":"Reports humidity exceeding the defined supervision condition at the monitored location.","example":"In a switchroom, water ingress, temperature, humidity and equipment-service alarms can be sent to the station controller with separate point names so an operator can identify the affected area. For this reference, the drawing identifies “Room humidity measurement” at the input and “High-humidity indication” at the output. Relative humidity varies with temperature.","drawings":"Start at the named input: Room humidity measurement. Identify its source device or document and the state represented on the drawing. Follow the named output: High-humidity indication. Cross-reference its destination and separate the command from confirmation that the equipment responded.","terms":[{"name":"Input","meaning":"Room humidity measurement"},{"name":"Output","meaning":"High-humidity indication"},{"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":["Room humidity measurement","SHHA","High-humidity indication"],"caption":"A reading guide. The entry's original illustration and input/output facts describe this application.","sources":[{"label":"Ventilation in MV substations","url":"https://www.electrical-installation.org/enwiki/Ventilation_in_MV_Substations"}],"profileId":"power-installation-room-environment"},"url":"https://eloragrid.ai/symbols/switchroom-humidity-high-alarm","illustration":{"url":"https://eloragrid.ai/tools/electrical-library/illustrations/switchroom-humidity-high-alarm.svg","scope":"Original educational concept; not an official standard graphic or product footprint","license":"https://creativecommons.org/licenses/by/4.0/"},"sources":[{"id":"pi26-ventilation","publisher":"Schneider Electric","title":"Ventilation in MV substations","url":"https://www.electrical-installation.org/enwiki/Ventilation_in_MV_Substations","scope":"Heat removal, condensation and environmental design context.","type":"manufacturer","checkedOn":"2026-11-03","reuse":"link-only","relevance":"Public technical context for switchroom environmental supervision. Heat removal, condensation and environmental design context. The application text and educational graphic are independently authored; the publisher does not certify this representation."}]}