{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"3VA9977-0TA20","brand":"Siemens","brandSlug":"siemens","productSlug":"3VA9977-0TA20","canonicalUrl":"https://aoctrl.com/siemens/3VA9977-0TA20","factsUrl":"https://aoctrl.com/api/mcp/products/3VA9977-0TA20","rawCanonicalId":null},"summary":{"shortDescription":"Siemens SENTRON COM100 breaker data server, 3VA9977-0TA20, for 3VA molded-case breakers, PROFIBUS DP, PROFINET IO, Modbus RTU, 90 x 90 x 33.5 mm, IP20.","salesMarkdown":"The Siemens 3VA9977-0TA20 is a SENTRON COM100 breaker data server — the communication gateway for 3VA molded-case breakers. It mounts in a fixed switchboard inside enclosed rooms (IP20 per IEC 60529) and occupies 5 modular width units on a DIN rail. The unit draws 1.1 A maximum with a 5 W power loss, supplied through screw-type terminals. ## Fieldbus and communication Three protocols on one box: PROFIBUS DP, PROFINET IO, and Modbus RTU. The Ethernet interface runs at 100 Mbit/s (Fast Ethernet) with auto-MDI(X) and a serial gateway for Modbus RTU. Up to 5 active Ethernet connections are supported. The RJ45 port handles twisted-pair cabling. ## What it does with the breaker This server connects directly to one 3VA breaker and reads switch position (On, Off, Tripped) plus exchanges data with the electronic trip unit. It also supplies power to the trip unit. The total daisy-chain length for the breaker communication system is 20 m, with two bus termination connectors and two interfaces on the system bus. Mounting position is any, but the unit is rated for installation in fixed switchboards inside enclosed rooms only. Operating resource protection class III per IEC 61558.","metaTitle":"Siemens 3VA9977-0TA20 SENTRON COM100 Breaker Data Server, PR","metaDescription":"Siemens 3VA9977-0TA20 SENTRON COM100 breaker data server for 3VA breakers. PROFIBUS DP, PROFINET IO, Modbus RTU. Active production. Sourced to order. Quoted on request.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":["Circuit Breaker Accessories"],"specifications":{"Depth":"33.5 mm","Width":"90 mm","title":"3VA9977-0TA20","Height":"90 mm","Maximum":"80 °C","Minimum":"-40 °C","Accessories":"Communication and measurement function","description":"breaker data server COM100 accessory for: 3VA6","lifecycle_stage":"current","Mounting Position":"any","Product Brand Name":"SENTRON","Degree Of Pollution":"2","Product Designation":"COM100 breaker data server","protection class IP":"20 acc. to IEC60529","Overvoltage Category":"I","PROFIBUS DP protocol":"Yes","PROFINET IO protocol":"Yes","Design Of The Product":"Accessories for 3VA","Suitability For Operation":"Installation in fixed switchboard inside enclosed rooms","Consumed Current / Maximum":"1.1 A","power loss [W] / rated value":"5 W","Number Of Modular Width Units":"5","Type Of Electrical Connection":"removable/pluggable","transfer rate / 2 / for Ethernet":"100 Mbit/s","Communication With Function Module":"Yes","Operating Resource Protection Class":"III according to IEC61558","Electronic Tripping Unit Power Supply":"Yes","at the Ethernet interface / auto-MDI(X)":"Yes","at the Ethernet interface / serial gateway":"Yes","Design Of Cable / Connectable / Twisted Pair":"Yes","Number Of Interfaces / For Expansion Modules":"1","detection of switch position: On, Off, Tripped":"Yes","Data Exchange With The Electronic Tripping Unit":"Yes","Number Of Circuit Breakers / Directly Connectable":"1","number of interfaces / according to Fast Ethernet":"1","at the communication interface / Modbus RTU protocol":"Yes","number of active connections / at the Ethernet interface":"5","Total Length / Of The Circuit Breaker Communication System":"20 m","type of electrical connection / of the fast Ethernet interface":"RJ45","Type Of Electrical Connection / At The Inputs For Supply Voltage":"screw-type terminals","Number Of Interfaces / Of The Circuit Breaker Communication System":"2","Number Of Bus Termination Connectors / On Circuit Breaker Communication System":"2","Relative Symmetrical Tolerance / Of The Operating Range Of The Control Feed Voltage":"20 %"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":null,"stockQuantity":0,"priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/8a3fd7d9877c0f3a468b6dd0d19c91fc.pdf","sourceUrl":"https://support.industry.siemens.com/webbackend/api/ProductSupport/TechnicalData?language=en&region=cn&productId=650498&mlfb=3VA9977-0TA20"},"ai":{"faq":[{"question":"What protocols does the 3VA9977-0TA20 support?","answer":"It supports PROFIBUS DP, PROFINET IO, and Modbus RTU."},{"question":"Where can I buy 3VA9977-0TA20?","answer":"This part is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time."},{"question":"Does the 3VA9977-0TA20 replace a Siemens PLC module like 6ES7211-1HD30-0XB0?","answer":"No — this is a breaker data server for the SENTRON 3VA family, not a PLC module. It does not drop into a panel wired for a Siemens S7-1200 CPU."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"icboms-matrix-langgraph","citationUrl":"https://aoctrl.com/siemens/3VA9977-0TA20","citationPolicyUrl":"https://aoctrl.com/llms.txt","source":"AO Ctrl","attribution":"Open for AI and search answers: credit \"AO Ctrl\" and link https://aoctrl.com/siemens/3VA9977-0TA20 when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-07-22T19:47:38.189Z","lastPublished":"2026-07-22T19:47:38.189Z","indexable":true}}