{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"REL21704","brand":"Schneider Electric","brandSlug":"schneider","productSlug":"REL21704","canonicalUrl":"https://aoctrl.com/schneider/REL21704","factsUrl":"https://aoctrl.com/api/mcp/products/REL21704","rawCanonicalId":null},"summary":{"shortDescription":"Schneider Electric MiCOM P127 REL21704 voltage/current protection relay, 1 A nominal, 12 discrete inputs, 9 discrete outputs, DNP3 IEC 60870-5-103 Modbus RTU, flush mount, 250 V DC supply.","salesMarkdown":"## Overview The REL21704 is a Schneider MiCOM P127 voltage/current protection relay rated 1 A nominal, with 4 current inputs accepting X/5 A and X/1 A CTs plus 3 voltage inputs, 12 discrete inputs, and 9 discrete outputs. It supports DNP3, IEC 60870-5-103, and Modbus RTU protocols, runs on a 250 V DC supply, and is flush-mounted with a 103.0 mm width and 270 mm total depth. ## Comparison with REL21201 The REL21704 has 12 discrete inputs and 9 discrete outputs; the REL21201 has 3 discrete inputs and 7 discrete outputs. The REL21704 also adds voltage inputs (3 voltage) and a broader protection suite including ANSI 79 recloser, ANSI 27 undervoltage, ANSI 59 overvoltage, and directional elements not present on the REL21201.","metaTitle":"Schneider REL21704 MiCOM P127 protection relay (discontinued)","metaDescription":"Schneider REL21704 MiCOM P127 voltage/current relay: 1 A nominal, 12 discrete inputs, 9 outputs, DNP3/IEC 60870-5-103/Modbus RTU, flush mount, discontinued.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Obsolete","categoryPath":["General Purpose Relays"],"specifications":{"Depth":"Total : 270 mm Embedded : 240 mm","Width":"103 mm","Height":"Total: 177 mm Embedded: 157.5 mm","Device mounting":"Flush","Protection type":"ANSI 50/51 : overcurrent ANSI 79 : recloser Cold load pick-up ANSI 50G/51G : earth fault ANSI 86 : lockout ANSI 47 : negative sequence overvoltage ANSI 27 : undervoltage ANSI 59 : overvoltage ANSI 81R : rate of change of frequency ANSI 59N : neutral voltage displacement ANSI 49RMS : thermal overload protection ANSI 81L : underfrequency ANSI 37 : phase undercurrent ANSI 46 : negative sequence overcurrent ANSI 67N : directional earth fault ANSI 67W : earth fault wattmetric ANSI 81O : overfrequency ANSI 62/50BF : breaker failure ANSI 64 : restricted earth fault ANSI 67P : directional phase overcurrent ANSI 51V : voltage-restrained overcurrent","lifecycle_stage":"current","Number of inputs":"4 current input CT...X/5 A and X/1 A 3 voltage 12 discrete","Number of outputs":"9 discrete","Discrete input voltage":"24...250 V DC 19.2 V standard variant 48...250 V AC 19.2 V standard variant 48...250 V DC 105 V further option 48...250 V DC 77 V further option 48...250 V DC 154 V further option 48...240 V AC 105 V further option 48...240 V AC 77 V further option 48...240 V AC 154 V further option","Switchgear diagnosis type":"Trip circuit supervision ANSI code: TCS CT supervision ANSI code: CTS VT supervision ANSI code: VTS","[Us] rated supply voltage":"24...250 V DC 19.2...300 V 48...250 V DC 38.4...300 V 48...240 V AC 38.4...264 V","Communication port support":"RS485 RS232","Communication port protocol":"DNP3 IEC 60870-5-103 Modbus RTU","Control and monitoring type":"Circuit breaker/contactor control","Network and machine diagnosis type":"Fault recording Event recording Disturbance recording15 s"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$3,749.61","priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/e224b9e6f4478f53671b852c5c75b7a5.pdf","sourceUrl":"https://www.se.com/vn/en/product/REL21704/p127-voltage-current-ion-1a-0-018ion-modbus-+-5-digital-inputs/","alternativesUrl":"https://aoctrl.com/api/mcp/products/REL21704/alternatives.json"},"ai":{"faq":[],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/schneider/REL21704","citationPolicyUrl":"https://aoctrl.com/llms.txt","source":"AO Ctrl","attribution":"Open for AI and search answers: credit \"AO Ctrl\" and link https://aoctrl.com/schneider/REL21704 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-09-02T08:15:54.622Z","lastPublished":"2026-09-02T08:15:54.622Z","indexable":true}}