# Solid State Relay, SPST-NO, 20 A, 460 VAC, DIN Rail, Spring, Zero Crossing

![Product image](https://novapart.co/image/farnell:3455033/)

**URL**: https://novapart.co/products/3RF2120-2AA24/solid-state-relay-spst-no-20-a-460-vac-din-rail
**SKU**: 3RF2120-2AA24
**Manufacturer**: SIEMENS
**Price**: €63.0300
**Stock**: 10+

## Specifications

| Parameter | Value |
|---|---|
| Product Range | SIRIUS 3RF21 Series |

## Datasheet

📄 [Download PDF](https://novapart.co/datasheet/farnell:3455033/)

**3RF2120-2AA24** 

**Data sheet** 

***phase-out type*** semiconductor relay, 1-phase 3RF2 width 22.5 mm, 20 A 48460 V / 110-230 V AC spring-loaded terminal for mounting on available cooling surfaces 

||***phase-out type*** semiconductor relay, 1-phase 3RF2 width 22.5 mm, 20 A 48-<br>460 V / 110-230 V AC spring-loaded terminal for mounting on available cooling<br>surfaces|
|---|---|
|**product brand name**|SIRIUS|
|**product designation**|solid-state relay|
|**design of theproduct**|1-pole|
|**product type designation**|3RF21|
|**General technical data**<br>~~ee~~||
|**product function**<br>~~ee~~|zero-point switching<br>~~ee~~|
|**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|3.5 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 CAS-No. 7439-92-1<br>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**|0.071 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 ... 460 V|
|— at 60 Hz rated value|48 ... 460 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**||
|● at 50 Hz|40 ... 506 V|
|● at 60 Hz|40 ... 506 V|
|**operational current rated value maximum**|20 A|



Subject to change without notice © Copyright Siemens 

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|**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**|AC|
|**control supply voltage 1 at AC**||
|● at 50 Hz|110 ... 230 V|
|● at 60 Hz|110 ... 230 V|
|**control supply voltage at AC**||
|● at 50 Hz full-scale value for signal<0> recognition|40 V|
|● at 60 Hz full-scale value for signal<0> recognition|40 V|
|● initial value for signal <1> detection|90 V|
|**control supply voltage frequency**||
|**● 1 rated value**|50 Hz|
|**● 2 rated value**|60 Hz|
|**symmetrical line frequency tolerance**|5 Hz|
|**control current at minimum control supply voltage**||
|● at AC|2 mA|
|control current at AC rated value|15 mA|
|**ON-delay time**|40 ms; additionallymax. one half-wave|
|**OFF-delay time**|40 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 auxiliary and control contacts||



Subject to change without notice © Copyright Siemens 

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|— solid|— solid|0.5 ... 1.5 mm²|
|---|---|---|
|— finelystranded with core endprocessing||0.5 ... 2.5 mm²|
|— 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**|||
|**operational current according to UL 508 rated value**||20 A|
|Electrical Safety|||
|**touch protection on the front according to IEC 60529**||finger-safe, for vertical contact from the front|
|**Ambient conditions**|||
|installation altitude at height above sea level maximum||1 000 m|
|**ambient temperature**|||
|● duringoperation||-25 ... +60 °C|
|● duringstorage||-55 ... +80 °C|
|**Electromagnetic compatibility**|||
|**conducted interference**|||
|● 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**||Class A for industrial environment|
|**field-bound HF interference emission according to CISPR11**||Class B for the domestic, business and commercial environments|
|**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||5SE2306; These fuses have a smaller rated current than the semiconductor<br>relays|
|**Approvals Certificates**|||
|**Environment**|**General Product Approval**||



**Environment General Product Approval** 

Subject to change without notice © Copyright Siemens 

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|Environmental Con-<br>firmations<br>~~—~~<br>ff<br>,<br>o><br>“|FAL|CE|UK<br>eE&|
|---|---|---|---|
|**EMV**<br>**Test Certificates**|**other**|||
|Type Test Certific-<br>Special Test Certific-|Confirmation|Miscellaneous|Confirmation|
|ates/Test Report<br>ate||||
|**other**<br>**Railway**||||
|Special Test Certific-<br>ate<br>~~=~~||||
|QC PASS||||
|**Further information**<br>~~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=3RF2120-2AA24||||
|**Cax online generator**||||
|https://support.automation.siemens.com/WW/CAXorder/default.aspx?lang=en&mlfb=3RF2120-2AA24||||
|**Service&Support (Manuals, Certificates, Characteristics, FAQs,...)**||||
|https://support.industry.siemens.com/cs/ww/en/ps/3RF2120-2AA24||||
|**Image database (product images, 2D dimension drawings, 3D models, device circuit diagrams, EPLAN macros, ...)**||**Image database (product images, 2D dimension drawings, 3D models, device circuit diagrams, EPLAN macros, ...)**||
|https://www.automation.siemens.com/bilddb/cax_de.aspx?mlfb=3RF2120-2AA24&lang=en||||



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**last modified:** 

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- [Supplier page](https://es.farnell.com/siemens/3rf2120-2aa24/solid-state-relays/dp/3455033)
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