{"schemaVersion":"matrix-product-facts/v1","identity":{"mpn":"TM251MESE","brand":"Schneider Electric","brandSlug":"schneider","productSlug":"TM251MESE","canonicalUrl":"https://aoctrl.com/schneider/TM251MESE","factsUrl":"https://aoctrl.com/api/mcp/products/TM251MESE","rawCanonicalId":null},"summary":{"shortDescription":"Schneider Electric Modicon M251 PLC, TM251MESE, 20.4-28.8 VDC supply, dual Ethernet ports, 64 MB system RAM, 128 MB flash backup, current production.","salesMarkdown":"## Communication and performance Dual Ethernet ports handle 10BASE-T/100BASE-TX, each with its own IP stack. That means one port can run a machine-level EtherNet/IP scanner while the second talks to a plant-wide Modbus TCP network — or serve as a web server via the embedded WebVisu. Cycle times: expect 10 ms for 16 EtherNet/IP connections, 64 ms for 64 Modbus TCP devices. For serial legacy gear, there's an RS485 port (15 m at 115.2 kbit/s) and an RS232 (3 m). USB is there for local programming at 480 Mbit/s. Memory-wise, the TM251MESE has 64 MB of system RAM and 128 MB of built-in flash for user program backup — no SD card required for basic retention. The real-time clock runs off a BR2032 lithium battery, which keeps the time for up to two years at 25 °C. Clock drift is under 60 seconds per month at that temperature, so scheduled events stay on track. An optional SD card (up to 16 GB) can hold extra logs or recipes. ## Environment and isolation Rated for pollution degree 2 environments — typical for dry, non-conductive dust conditions inside an enclosure. It handles 15 gn shock for 11 ms and vibration as per IEC 60068-2-6: 3.5 mm amplitude up to 8.4 Hz, then 3 gn up to 150 Hz. Operating altitude goes to 2000 m; storage altitude to 3000 m. Humidity tolerance is 10–95% non-condensing across operation and storage. Isolation between supply and ground is a single 500 V AC barrier — non-isolated between supply and internal logic. That's typical for PLCs in this class; just ensure the external 24 VDC supply is properly grounded and filtered to avoid ground loops.","metaTitle":"Schneider TM251MESE Modicon M251 PLC, Current Production","metaDescription":"TM251MESE Modicon M251 PLC: 20.4-28.8 VDC, dual 10/100 Ethernet (EtherNet/IP, Modbus TCP), 64 MB RAM, 128 MB flash, CE/UL/IEC/Marine. Active production, sourced to order upon RFQ.","metaKeywords":null},"attributes":{"series":null,"packageCase":null,"mountingType":null,"rohsStatus":null,"productStatus":"Active","categoryPath":[],"specifications":{"Depth":"3.7 in (95 mm)","Width":"2.1 in (54 mm)","Height":"3.5 in (90 mm)","Supply":"Serial)serial link supply 5 V, <200 mA","Marking":"CE","Category":"US10MSX22533","Standards":"ANSI/ISA 12-12-01 CSA C22.2 No 142 CSA C22.2 No 213 IEC 61131-2:2007 Marine specification (LR, ABS, DNV, GL) UL 508","Cycle time":"10 ms 16 EtherNet/IP 64 ms 64 Modbus TCP","Insulation":"Non-insulated between supply and internal logic Between supply and ground 500 V AC","Backup time":"2 years 77 °F (25 °C)","Clock drift":"<= 60 s/month 77 °F (25 °C)","Battery type":"BR2032 lithium non-rechargeable 4 year(s)","Web services":"Web server","Port Ethernet":"Ethernet 1 10BASE-T/100BASE-TX - 2 copper cable Ethernet 2 10BASE-T/100BASE-TX - 1 copper cable","Data backed up":"128 MB built-in flash memory backup of user programs","Inrush current":"50 A","Realtime clock":"With","Memory capacity":"64 MB system memory RAM","Surge withstand":"1 kV shielded cable common mode IEC 61000-4-5 1 kV power lines common mode IEC 61000-4-5 0.5 kV power lines differential mode IEC 61000-4-5","lifecycle_stage":"current","Local signalling":"1 LED (green) for PWR 1 LED (green) for RUN 1 LED (red) for module error (ERR) 1 LED (red) for I/O error (I/O) 1 LED (green) for SD card access (SD) 1 LED (red) for BAT 1 LED (green) for SL 1 LED (red) for bus fault on TM4 (TM4) 1 LED (green) for Ethernet activity (ETH1) 1 LED (green) for Ethernet activity (ETH2)","Mounting support":"Top hat type TH35-15 rail IEC 60715 Top hat type TH35-7.5 rail IEC 60715 plate or panel with fixing kit","Pollution degree":"2","Range of Product":"Modicon M251","Shock resistance":"15 gn 11 ms","Storage altitude":"0...9842.5 ft (0...3000 m)","Relative humidity":"10...95 %, without condensation in operation) 10...95 %, without condensation in storage)","Transmission rate":"1.2...115.2 kbit/s (115.2 kbit/s by default) 49.2 ft (15 m) RS485 1.2...115.2 kbit/s (115.2 kbit/s by default) 9.8 ft (3 m) RS232 480 Mbit/s 9.8 ft (3 m) USB","Operating altitude":"0...6561.68 ft (0...2000 m)","Vibration resistance":"3.5 mm 5...8.4 Hz symmetrical rail 3 gn 8.4...150 Hz symmetrical rail 3.5 mm 5...8.4 Hz panel mounting 3 gn 8.4...150 Hz panel mounting","Application structure":"4 cyclic master tasks 8 event tasks 3 cyclic master tasks + 1 freewheeling task 8 external event tasks","Communication service":"Downloading IEC VAR ACCESS Modbus TCP client Modbus TCP server Modbus TCP slave device Monitoring NGVL Programming Updating firmware SMS notifications DHCP client Eth1) DHCP server Eth2) Ethernet/IP originator Eth2) Ethernet/IP target Eth1, Eth2) Ethernet/IP scanner Eth2) Modbus TCP I/O Scanner and Messaging Eth2) FDR FTP client/server SNMP client/server SQL client Send and receive email from the controller based on TCP/UDP library Web server (WebVisu & XWeb system) OPC UA server DNS client","Electrical connection":"removable screw terminal block power supply pitch 5.08 mm)","Nbr. of units in pkg.":"1","Supply voltage limits":"20.4...28.8 V","Data storage equipment":"<= 16 GB SD card optional)","Power consumption in W":"32.6...40.4 W with max number of I/O expansion module)","IP degree of protection":"IP20 with protective cover in place","Immunity to microbreaks":"10 ms","Electromagnetic emission":"Conducted emissions 120...69 dBµV/m QP power lines)10...150 kHz IEC 55011 Conducted emissions 63 dBμV/m QP power lines)1.5...30 MHz IEC 55011 Radiated emissions 40 dBμV/m QP class A 10 m)30...230 MHz IEC 55011 Conducted emissions 79...63 dBμV/m QP power lines)150...1500 kHz IEC 55011 Radiated emissions 47 dBμV/m QP class A 10 m)230...1000 MHz IEC 55011","Product or Component Type":"Logic controller","[Us] rated supply voltage":"24 V DC","Integrated connection type":"USB port mini B USB 2.0 Non isolated serial link serial RJ45 RS232/RS485 Dual-port Ethernet 1 RJ45 Ethernet port Ethernet 2 RJ45","Number of server device(s)":"16 EtherNet/IP 64 Modbus TCP","Communication port protocol":"USB port USB - SoMachine-Network Non isolated serial link Modbus master/slave - RTU/ASCII or SoMachine-Network","Maximum number of connections":"8 Modbus server 8 Modbus client 16 Ethernet/IP target 4 FTP server 10 web server 8 SoMachine protocol","Resistance to fast transients":"2 kV IEC 61000-4-4 power lines) 1 kV IEC 61000-4-4 Ethernet line) 1 kV IEC 61000-4-4 serial link)","Execution time for 1 KInstruction":"0.3 ms event and periodic task 0.7 ms other instruction","Ambient Air Temperature for Storage":"-13...158 °F (-25...70 °C)","Resistance to conducted disturbances":"10 V 0.15...80 MHz IEC 61000-4-6 3 V 0.1...80 MHz Marine specification (LR, ABS, DNV, GL) 10 V spot frequency (2, 3, 4, 6.2, 8.2, 12.6, 16.5, 18.8, 22, 25 MHz) Marine specification (LR, ABS, DNV, GL)","Resistance to electromagnetic fields":"9.1 V/m (10 V/m) 80 MHz...1 GHz IEC 61000-4-3 2.7 V/m (3 V/m) 1.4 GHz...2 GHz IEC 61000-4-3 0.9 V/m (1 V/m) 2 GHz...3 GHz IEC 61000-4-3","Ambient air temperature for operation":"14...95 °F (-10...35 °C) vertical installation) 14...131 °F (-10...55 °C) horizontal installation)","Resistance to electrostatic discharge":"8 kV in air IEC 61000-4-2 4 kV on contact IEC 61000-4-2"}},"commercial":{"minOrderQty":null,"leadTime":null,"referencePrice":"$311.15 – $798.46","priceTiers":null},"links":{"datasheetUrl":"https://cdn.aoctrl.com/48033f6ea447a4c057ad3d481ca43479.pdf","sourceUrl":null,"alternativesUrl":"https://aoctrl.com/api/mcp/products/TM251MESE/alternatives.json"},"ai":{"faq":[{"question":"What compliance documentation does the TM251MESE have?","answer":"The controller carries CE marking and complies with UL 508, ANSI/ISA 12-12-01, CSA C22.2 Nos. 142 and 213, IEC 61131-2, and marine specifications from LR, ABS, DNV, and GL."},{"question":"What is the power supply range for the TM251MESE?","answer":"The supply voltage is 20.4–28.8 VDC, with a typical power consumption of 32.6–40.4 W when using the maximum number of I/O expansion modules."},{"question":"How does the TM251MESE retain programs and real-time clock?","answer":"Programs are backed up to 128 MB of built-in flash memory. The real-time clock is powered by a BR2032 lithium battery that provides up to 2 years of backup at 25 °C."}],"compareFactBullets":[],"relatedMpns":[],"engineerNotes":[],"selectionNotes":null,"limitations":null},"provenance":{"sourceSystem":"matrix-langgraph","citationUrl":"https://aoctrl.com/schneider/TM251MESE","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/TM251MESE when reusing this data. Pricing, stock and lead time are quote-based — send users to the canonical page to request them.","lastUpdated":"2026-09-02T08:21:01.794Z","lastPublished":"2026-09-02T08:21:01.794Z","indexable":true}}