{"requirement_id":"JDDG25-14.12.2.2-R02","source":{"document":"Japan District Design Guide","version":"9.0","publication_date":"2025-04","chapter":"14","section":"14.12.2.2","title":"TRANSFORMER GROUNDING","page_printed":275,"page_pdf":305,"fact":"If a delta tap is taken from a wye system, the neutral should be extended to the building service to provide a low-impedance fault path and proper overcurrent-device operation.","modality":"should","strength":"recommended"},"localization_ja":{"language":"ja","title_ja":"変圧器接地","title_status":"controlled_editorial","fact_ja":null,"fact_translation_status":"pending","modality_rendering_ja":"～することが望ましい／～を推奨する","strength_label_ja":"推奨","translation_priority":"medium","translation_notes":[],"title_translation_provenance":"editorial_controlled","fact_translation_provenance":"not_translated","publication_eligible":false},"references":[],"meaning":{"engineering_basis":"Provide a low-impedance fault path and proper overcurrent-device operation.","engineering_basis_source":"source_explicit","engineering_interpretation":null,"interpretation_confidence":null},"risk":{"failure_modes":[],"failure_mode_source":"not_stated","failure_domains":[]},"quality":{"source_status":"normal","data_quality_flag":"normal"},"applicability":{"applicability_class":"conditional_text","evaluation_mode":"human_review","evaluation_scope":"project","input_semantics":"human_review","source_condition_text":"a delta tap is taken from a wye system","trigger":null,"approval_gate":null,"exception_condition":null,"condition_provenance":"source_explicit","normalization_provenance":"text_only"},"lifecycle":{"primary_phase":"design","primary_phase_label":"Design","applicable_phases":["design","installation"],"phase_links":[{"phase":"design","provenance":"jddg_cross_section_explicit","basis":"Linked to separate JDDG Section 14.8 design evidence/submittal requirements.","phase_label":"Design"},{"phase":"installation","provenance":"editorial_derived","basis":"Normalized from verification stage `installation`.","phase_label":"Installation / Construction"}]},"responsibility":{"primary_workflow_owner":"ACT-DESIGNER-AE","primary_workflow_owner_name":"Designer / A-E","actor_assignment_status":"workflow_only","actors":[{"actor_id":"ACT-DESIGNER-AE","actor_name":"Designer / A-E","actor_class":"project_delivery","source_named":true,"relation_type":"workflow_owner","provenance":"editorial_derived","lifecycle_phase":"design","lifecycle_phase_label":"Design","basis":"Workflow owner assigned from lifecycle phase for checklist routing; not a contractual responsibility statement."},{"actor_id":"ACT-CONSTRUCTION-CONTRACTOR","actor_name":"Construction Contractor","actor_class":"project_delivery","source_named":true,"relation_type":"workflow_owner","provenance":"editorial_derived","lifecycle_phase":"installation","lifecycle_phase_label":"Installation / Construction","basis":"Workflow owner assigned from lifecycle phase for checklist routing; not a contractual responsibility statement."}]},"verification":{"method":"design_and_installation_conformance_review","stage":["design","installation"],"acceptance_criteria":null,"evidence_required":["design_document_or_installed_condition"],"verification_provenance":"editorial_derived","evidence_provenance":"jddg_cross_section_explicit","audit_status":"derived_check_method_not_stated_by_source","audit_confidence":"medium","acceptance_provenance":"not_stated_in_jddg","evidence_type_ids":["EV-DESIGN-ANALYSIS-FINAL","EV-LIGHTNING-GROUNDING-PLAN","EV-SHORT-CIRCUIT-ANALYSIS","EV-INTERMEDIATE-ONE-LINE","EV-PRODUCT-DATA","EV-FINAL-CALCULATIONS","EV-FINAL-DRAWINGS","EV-CONTRACTOR-SC-COORDINATION"],"supporting_source_requirements":["JDDG25-14.8.4.3-R01","JDDG25-14.8.3.1-R05","JDDG25-14.8.3.3-R02","JDDG25-14.8.3.1-R06","JDDG25-14.8.2.3-R04","JDDG25-14.8.3.1-R02","JDDG25-14.8.4.3-R02","JDDG25-14.8.4.1-R01","JDDG25-14.8.4.1-R03","JDDG25-14.8.3.2-R05"],"source_support_scope":"design_submittal_or_analysis"},"resolved_evidence":[{"evidence_type_id":"EV-DESIGN-ANALYSIS-FINAL","name":"Final Design Analysis compliance verification","source_requirement_ids":["JDDG25-14.8.4.3-R01"],"stage":["final_design"],"source_scope":"Final Design Analysis should support and verify design compliance with project requirements."},{"evidence_type_id":"EV-LIGHTNING-GROUNDING-PLAN","name":"Lightning-protection and grounding plan","source_requirement_ids":["JDDG25-14.8.3.1-R05"],"stage":["intermediate_design"],"source_scope":"Plans show grounding rods, conductors, air terminals, sizes, dimensions, and material types."},{"evidence_type_id":"EV-SHORT-CIRCUIT-ANALYSIS","name":"Short-circuit analysis","source_requirement_ids":["JDDG25-14.8.3.3-R02"],"stage":["intermediate_design"],"source_scope":"Intermediate calculations include short-circuit analysis."},{"evidence_type_id":"EV-INTERMEDIATE-ONE-LINE","name":"Intermediate one-line / riser diagram","source_requirement_ids":["JDDG25-14.8.3.1-R06"],"stage":["intermediate_design"],"source_scope":"One-line/riser diagrams show conduit/conductor sizes, panels, breaker frame/trip values, and short-circuit ratings."},{"evidence_type_id":"EV-PRODUCT-DATA","name":"Major equipment product data / datasheets","source_requirement_ids":["JDDG25-14.8.2.3-R04","JDDG25-14.8.3.1-R02"],"stage":["concept_design","intermediate_design"],"source_scope":"Design analysis/detail sheets include product data and salient characteristics for proposed major equipment."},{"evidence_type_id":"EV-FINAL-CALCULATIONS","name":"Final engineering calculations","source_requirement_ids":["JDDG25-14.8.4.3-R02"],"stage":["final_design"],"source_scope":"All final calculations are included in the Final Design Analysis."},{"evidence_type_id":"EV-FINAL-DRAWINGS","name":"Final contract drawings and details","source_requirement_ids":["JDDG25-14.8.4.1-R01","JDDG25-14.8.4.1-R03"],"stage":["final_design"],"source_scope":"Final drawings contain required details and are checked for discrepancies and interdisciplinary compatibility."},{"evidence_type_id":"EV-CONTRACTOR-SC-COORDINATION","name":"Contractor short-circuit study and time-coordination curves","source_requirement_ids":["JDDG25-14.8.3.2-R05"],"stage":["contractor_submittal"],"source_scope":"For the stated demand/critical-process condition, specifications should require contractor short-circuit study and time-coordination curves."}],"supporting_source_requirements":[{"requirement_id":"JDDG25-14.8.4.3-R01","section":"14.8.4.3","title":"DESIGN ANALYSIS","fact":"Final design analysis should support and verify that the design complies with project requirements."},{"requirement_id":"JDDG25-14.8.3.1-R05","section":"14.8.3.1","title":"DRAWINGS","fact":"Intermediate design is to include lightning-protection and grounding plans showing rods, conductors, air terminals, sizes, dimensions, and material types."},{"requirement_id":"JDDG25-14.8.3.3-R02","section":"14.8.3.3","title":"DESIGN ANALYSIS","fact":"Intermediate design calculations should include short-circuit analysis."},{"requirement_id":"JDDG25-14.8.3.1-R06","section":"14.8.3.1","title":"DRAWINGS","fact":"Intermediate one-line/riser diagrams are to show conduit and conductor sizes, panels, breaker frame sizes, trip amps, and short-circuit ratings."},{"requirement_id":"JDDG25-14.8.2.3-R04","section":"14.8.2.3","title":"DESIGN ANALYSIS","fact":"Concept Design Analysis appendices should include product data for proposed major electrical equipment, using Japanese product data to the greatest extent possible particularly for luminaires."},{"requirement_id":"JDDG25-14.8.3.1-R02","section":"14.8.3.1","title":"DRAWINGS","fact":"Chosen systems and equipment should be detailed with dimensions, salient characteristics, and related notes."},{"requirement_id":"JDDG25-14.8.4.3-R02","section":"14.8.4.3","title":"DESIGN ANALYSIS","fact":"All final calculations are to be included in the Final Design Analysis."},{"requirement_id":"JDDG25-14.8.4.1-R01","section":"14.8.4.1","title":"DRAWINGS","fact":"Final drawings should contain all details required for the final package."},{"requirement_id":"JDDG25-14.8.4.1-R03","section":"14.8.4.1","title":"DRAWINGS","fact":"Final drawings are to be checked for discrepancies and compatibility with specifications and other disciplines."},{"requirement_id":"JDDG25-14.8.3.2-R05","section":"14.8.3.2","title":"SPECIFICATIONS","fact":"For designs with demand of at least 500 kVA or processes where loss of function is undesirable, specifications should require the construction contractor to provide a short-circuit study and time-coordination curves."}],"references_resolved":[]}