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3RF2120-2AA45
Solid State Relay, SPST-NO, 20 A, 600 VAC, DIN Rail, Spring, Zero Crossing
⚠️ Reference pricing provided. In case of supply shortages, we will connect you with our trusted procurement partners to ensure your project's continuity.
- Manufacturer: SIEMENS
- Product type:
- Product Range: SIRIUS 3RF21 Series
| Delivery and price | |
|---|---|
| Units per pack | 1 |
| Price | 61.42 € |
| Current stock | 10+ |
| Lead time | 30 days |
**3RF2120-2AA45** **Data sheet** ***phase-out type*** semiconductor relay, 1-phase 3RF2 width 22.5 mm, 20 A 48600 V / 4-30 V DC spring-loaded terminal blocking voltage 1200 V for mounting on available cooling surfaces ||***phase-out type*** semiconductor relay, 1-phase 3RF2 width 22.5 mm, 20 A 48-<br>600 V / 4-30 V DC spring-loaded terminal blocking voltage 1200 V for mounting on<br>available cooling surfaces| |---|---| |**product brand name**|SIRIUS| |**product designation**|solid-state relay| |**design of theproduct**|1-pole| |**product type designation**|3RF21| |**manufacturer's article number**|| |●_3 of the accessories that can be ordered|3RF2900-0EA18| |**product designation**|| |● _3 of the accessories that can be ordered|converter| |**General technical data**<br>~~a~~|| |**product function**<br>~~a~~|zero-point switching<br>~~a~~| |**power loss[V·A] maximum**|28.6 VA| |**power loss[W] for rated value of the current**|| |● at AC in hot operatingstate|28.6 W| |● at AC in hot operatingstateperpole|28.6 W| |● without load current share typical|0.5 W| |**insulation voltage rated value**|600 V| |surge voltage resistance of main circuit rated value|6 kV| |**protection class IP**|IP20| |protection class IP on the front accordingto IEC 60529|IP20| |**shock resistance according to IEC 60068-2-27**|15g/ 11 ms| |**vibration resistance according to IEC 60068-2-6**|2g| |**reference code according to IEC 81346-2**|Q| |**Substance Prohibitance(day/month/year)**|05/28/2009| |**SVHC substance name**|Lead monoxide (lead oxide) CAS-No. 1317-36-8<br>2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one CAS-No. 71868-<br>10-5<br>Melamine CAS-No. 108-78-1| |**Net Weight**|0.068 kg| |**Main circuit**<br>~~ee~~|| |**number ofpoles for main current circuit**<br>~~ee~~|1<br>~~ee~~| |**number of NO contacts for main contacts**|1| |**number of NC contacts for main contacts**|0| |**type of voltage of the operating voltage**|AC| |**operating voltage**|| |● at AC|| |— at 50 Hz rated value|48 ... 600 V| |— at 60 Hz rated value|48 ... 600 V| |**operating frequency rated value**|50 ... 60 Hz| |**relative symmetrical tolerance of the operating frequency**|10 %| |**operating range relative to the operating voltage at AC**|| Subject to change without notice © Copyright Siemens 3RF21202AA45 Page 1/5 5/31/2026 |● at 50 Hz|40 ... 660 V| |---|---| |● at 60 Hz|40 ... 660 V| |**operational current rated value maximum**|20 A| |**operational current**|| |● at AC-1 at 400 V rated value|20 A| |● at AC-51 rated value|20 A| |● accordingto UL 508 rated value|20 A| |**ampacity maximum**|20 A| |**operational current minimum**|100 mA| |**rate of voltage rise at the thyristor for main contacts**<br>**maximumpermissible**|500 V/µs| |**blocking voltage at the thyristor for main contacts**<br>**maximumpermissible**|1 200 V| |**reverse current of the thyristor**|10 mA| |**derating temperature**|40 °C| |**surge current resistance rated value**|200 A| |**I2t value maximum**|200 A²·s| |**Control circuit/ Control**|| |**type of voltage of the control supply voltage**|DC| |**control supply voltage 1 at DC rated value maximum**<br>**permissible**|30 V| |**control supply voltage 1 at DC**|4 ... 30 V| |**control supply voltage at DC**|| |● initial value for signal <1> detection|4 V| |● full-scale value for signal<0> recognition|1 V| |**control current at minimum control supply voltage**|| |● at DC|13 mA| |control current at DC rated value|15 mA| |**ON-delay time**|1 ms; additionallymax. one half-wave| |**OFF-delay time**|1 ms; additionallymax. one half-wave| |**Installation/ mounting/ dimensions**|| |fasteningmethod side-by-side mounting|Yes| |**fastening method**|screw fixing| |**design of the thread of the screw for securing the**<br>**equipment**|M4| |**tightening torque of fixing screw maximum**|1.5 N·m| |**tightening torque[lbf·in] of fixing screw maximum**|13 lbf·in| |**height**|85 mm| |**width**|22.5 mm| |**depth**|48 mm| |**Connections/ Terminals**|| |**product component removable terminal for auxiliary and**<br>**control circuit**|Yes| |**type of electrical connection**|| |● for main current circuit|spring-loaded terminals| |● for auxiliaryand control circuit|spring-loaded terminals| |**type of connectable conductor cross-sections**|| |● for main contacts|| |— solid|2x(0.5 ... 2.5 mm²)| |— finelystranded with core endprocessing|2x(0.5 ... 1.5 mm²)| |— finelystranded without core endprocessing|2x(0.5 ... 2.5 mm²)| |● for AWG cables for main contacts|2x(18 ... 14)| |**connectable conductor cross-section for main contacts**|| |● solid or stranded|0.5 ... 2.5 mm²| |● finelystranded with core endprocessing|0.5 ... 1.5 mm²| |● finelystranded without core endprocessing|0.5 ... 2.5 mm²| |**type of connectable conductor cross-sections**|| |● for auxiliaryand control contacts|| |— solid|0.5 ... 1.5 mm²| |— finely stranded with core end processing|0.5 ... 2.5 mm²| Subject to change without notice © Copyright Siemens 3RF21202AA45 Page 2/5 5/31/2026 |— finelystranded without core endprocessing|— finelystranded without core endprocessing|0.5 ... 2.5 mm²| |---|---|---| |● for AWG cables for auxiliaryand control contacts||1x(20 ... 12)| |**AWG number as coded connectable conductor cross**<br>**section for main contacts**||14 ... 10| |**tightening torque**||| |● for main contacts with screw-type terminals||2 ... 2.5 N·m| |**stripped length of the cable**||| |● for main contacts||10 mm| |● for auxiliaryand control contacts||10 mm| |**UL/CSA ratings**<br>~~ee~~||| |**operational current according to UL 508 rated value**<br>~~ee~~<br>~~ee~~||20 A<br>~~ee~~<br>~~ee~~| |Electrical Safety<br>~~ee~~||| |**touch protection on the front according to IEC 60529**<br>~~ee~~||finger-safe, for vertical contact from the front<br>~~ee~~| |**Ambient conditions**<br>~~ee~~||| |installation altitude at height above sea level maximum<br>~~ee~~||1 000 m<br>~~ee~~| |**ambient temperature**||| |● duringoperation||-25 ... +60 °C| |● duringstorage||-55 ... +80 °C| |**Electromagnetic compatibility**<br>~~a~~||| |**conducted interference**<br>~~a~~||~~a~~| |● due to burst accordingto IEC 61000-4-4||2 kV / 5 kHz, behavior criterion 2| |● due to conductor-earth surge accordingto IEC 61000-4-5||2 kV, behavior criterion 2| |● due to conductor-conductor surge according to IEC<br>61000-4-5||1 kV, behavior criterion 2| |● due to high-frequency radiation according to IEC 61000-<br>4-6||140 dBuV in the frequency range 0.15 ... 80 MHz, behavior criterion 1| |**field-based interference according to IEC 61000-4-3**||80 MHz ... 1 GHz 10 V/m, behavior criterion 1| |**electrostatic discharge according to IEC 61000-4-2**||4 kV contact discharging/ 8 kV air discharging, behavior criterion 2| |**conducted HF interference emissions according to**<br>**CISPR11**<br>~~re~~||Class A for industrial environment<br>~~re~~| |**field-bound HF interference emission according to CISPR11**<br>~~re~~||Class B for the domestic, business and commercial environments<br>~~re~~| |**Short-circuit protection, design of the fuse link**||| |manufacturer's article number||| |● of gS fuse for semiconductor protection at NH design<br>usable||3NE1813-0; These fuses have a smaller rated current than the semiconductor<br>relays| |● of full range R fuse link for semiconductor protection at<br>cylindrical design usable||5SE1320| |● of back-up R fuse link for semiconductor protection at NH<br>design usable||3NE8015-1| |● of back-up R fuse link for semiconductor protection at<br>cylindrical design 10 x 38 mm usable||3NC1016; These fuses have a smaller rated current than the semiconductor<br>relays| |● of back-up R fuse link for semiconductor protection at<br>cylindrical design 14 x 51 mm usable||3NC1425| |● of back-up R fuse link for semiconductor protection at<br>cylindrical design 22 x 58 mm usable||3NC2220| |manufacturer's article number of thegG fuse||| |● at NH design usable||3NA6801; These fuses have a smaller rated current than the semiconductor<br>relays| |● at NH design usable note||These fuses have a smaller rated current than the semiconductor relays| |● at cylindrical design 14 x 51 mm usable||3NW6101-1; These fuses have a smaller rated current than the semiconductor<br>relays| |● at cylindrical design 14 x 51 mm usable note||These fuses have a smaller rated current than the semiconductor relays| |manufacturer's article number||| |● of NEOZED fuse usable<br>~~a~~||5SE2306; These fuses have a smaller rated current than the semiconductor<br>relays<br>~~a~~| |**Approvals Certificates**<br>~~a~~||| |**Environment**<br>~~a~~|**General Product Approval**<br>~~a~~|| Subject to change without notice © Copyright Siemens 3RF21202AA45 Page 3/5 5/31/2026 **==> picture [479 x 95] intentionally omitted <==** **----- Start of picture text -----**<br> EMV Test Certificates other<br>Type Test Certific- Special Test Certific- Confirmation Miscellaneous Confirmation<br>ates/Test Report ate<br>other<br>**----- End of picture text -----**<br> **Railway** - Special Test Certific ~~—~~ ate **Further information** ~~ee~~ **Information on the packaging** https://support.industry.siemens.com/cs/ww/en/view/109813875 **Information for data generation and storage** https://support.industry.siemens.com/cs/ww/en/view/109995012 **Information- and Downloadcenter (Catalogs, Brochures,…)** https://www.siemens.com/ic10 **Industry Mall (Online ordering system)** https://mall.industry.siemens.com/mall/en/en/Catalog/product?mlfb=3RF2120-2AA45 **Cax online generator** https://support.automation.siemens.com/WW/CAXorder/default.aspx?lang=en&mlfb=3RF2120-2AA45 **Service&Support (Manuals, Certificates, Characteristics, FAQs,...)** https://support.industry.siemens.com/cs/ww/en/ps/3RF2120-2AA45 **Image database (product images, 2D dimension drawings, 3D models, device circuit diagrams, EPLAN macros, ...)** https://www.automation.siemens.com/bilddb/cax_de.aspx?mlfb=3RF2120-2AA45&lang=en ~~OO~~ 47.5 Subject to change without notice © Copyright Siemens 3RF21202AA45 Page 4/5 5/31/2026 **==> picture [464 x 540] intentionally omitted <==** **----- Start of picture text -----**<br> -Q<br>|<br>|<br>|<br>|<br>|<br>|<br>|<br>ee<br>40<br>(CCE 35 «OEE<br>CeCe CeCe) 30 CRRERRES<br>Rthha<br>POPP 25 1,3 K/W<br>1,6 K/W<br>CCPC eee) $6 20 GREECE = 2 K/W<br>2,5 K/W<br>CCCer eee) 15 GRESEEEEEE 3,2 K/W<br>4 K/W<br>COCO 10 AS 5 K/W<br>6 K/W<br>CORT CCCI] 5 6EEREEREESSSS 8 K/W<br>12 K/W<br>SPP CCC) 6 0 PeREEEEEESEFS<br>EEE EEL) $= Eeececc eee<br>2 6 10 14 18 22 0 10 20 30 40 50 60<br>Device curren t / Gerätestrom I e (A) Ambien t tempe rature/ Umgebung stempe ratur T a (°C)<br>last modified: 4/4/2026 a<br>+ -<br>1L<br>A1 A2<br>T<br>2<br>(A)<br> (W) I e<br> M<br>P<br> (W)<br> M<br>P<br>/ Modulverlustleistung<br>loss<br>power<br>Module<br>**----- End of picture text -----**<br> 4/4/2026 Subject to change without notice © Copyright Siemens 3RF21202AA45 Page 5/5 5/31/2026
Updated at June 10, 2026
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