3RF2255-1AC45

**3RF2255-1AC45** 

**Data sheet** 

***phase-out type*** semiconductor relay, 3-phase 3RF2 55 A / 40 °C 48-600 V / 4- 30 V DC 3-phase controlled screw terminal blocking voltage 1200 V for mounting on available cooling surfaces 

|Att<br>a) °<br>|~<br>~2.¢|***phase-out type*** semiconductor relay, 3-phase 3RF2 55 A / 40 °C 48-600 V / 4-<br>30 V DC 3-phase controlled screw terminal blocking voltage 1200 V for mounting<br>on available cooling surfaces|
|---|---|
|**product brand name**|SIRIUS|
|**product designation**|solid-state relay|
|**design of theproduct**|3-pole controlled|
|**product type designation**|3RF22|
|**manufacturer's article number**||
|●_2 of the accessories that can be ordered|3RF2900-0EA18|
|**product designation**||
|● _2 of the accessories that can be ordered|converter|
|**General technical data**<br>~~ee~~||
|**product function**<br>~~ee~~|zero-point switching<br>~~ee~~|
|**power loss[W] for rated value of the current**||
|● at AC in hot operatingstate|226 W|
|● at AC in hot operatingstateperpole|226 W|
|● without load current share typical|0.9 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)**|07/01/2006|
|**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**|0.139 kg|
|**Main circuit**<br>~~a~~||
|**number ofpoles for main current circuit**<br>~~a~~|3<br>~~a~~|
|**number of NO contacts for main contacts**|3|
|**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**||



3RF22551AC45 Page 1/5 

Subject to change without notice © Copyright Siemens 

6/2/2026 

|● at 50 Hz|40 ... 660 V|
|---|---|
|● at 60 Hz|40 ... 660 V|
|**operational current rated value maximum**|55 A|
|**operational current**||
|● at AC-1 at 400 V rated value|55 A|
|● at AC-51 rated value|50 A|
|● accordingto UL 508 rated value|50 A|
|**ampacity maximum**|55 A|
|**operational current minimum**|500 mA|
|**rate of voltage rise at the thyristor for main contacts**<br>**maximumpermissible**|100 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**|600 A|
|**I2t value maximum**|1 800 A²·s|
|**Control circuit/ Control**||
|**type of voltage of the control supply voltage**|DC|
|**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|22 mA|
|control current at DC rated value|30 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**|95 mm|
|**width**|45 mm|
|**depth**|47 mm|
|**Connections/ Terminals**||
|**product component removable terminal for auxiliary and**<br>**control circuit**|Yes|
|**type of electrical connection**||
|● for main current circuit|screw-type terminals|
|● for auxiliaryand control circuit|screw-type terminals|
|**type of connectable conductor cross-sections**||
|● for main contacts||
|— solid|2x(1.5 ... 2.5 mm²), 2x(2.5 ... 6 mm²)|
|— finelystranded with core endprocessing|2x(1 ... 2.5 mm²), 2x(2.5 ... 6 mm²), 1x 10 mm²|
|● for AWG cables for main contacts|2x(14 ... 10)|
|**connectable conductor cross-section for main contacts**||
|● solid or stranded|1.5 ... 6 mm²|
|● finelystranded with core endprocessing|1 ... 10 mm²|
|**type of connectable conductor cross-sections**||
|● for auxiliaryand control contacts||
|— solid|1x(0.5 ... 2.5 mm²), 2x(0.5 ... 1 mm²)|
|— finelystranded with core endprocessing|1x(0.5 ... 2.5 mm²), 2x(0.5 ... 1 mm²)|
|— finelystranded without core endprocessing|1x(0.5 ... 2.5 mm²), 2x(0.5 ... 1 mm²)|
|● for AWG cables for auxiliaryand control contacts|1x(20 ... 12)|
|**AWG number as coded connectable conductor cross**<br>**section for main contacts**|10 ... 14|



3RF22551AC45 Page 2/5 

Subject to change without notice © Copyright Siemens 

6/2/2026 

|**tightening torque**|**tightening torque**||
|---|---|---|
|● for main contacts with screw-type terminals||2 ... 2.5 N·m|
|● for auxiliary and control contacts with screw-type<br>terminals||0.5 ... 0.6 N·m|
|**tightening torque[lbf·in]**|||
|● for main contacts with screw-type terminals||18 ... 22 lbf·in|
|● for auxiliary and control contacts with screw-type<br>terminals||4.5 ... 5.3 lbf·in|
|**design of the thread of the connection screw**|||
|● for main contacts||M4|
|● of the auxiliaryand control contacts||M3|
|**stripped length of the cable**|||
|● for main contacts||10 mm|
|● for auxiliaryand control contacts||7 mm|
|**UL/CSA ratings**<br>~~a~~|||
|**operational current according to UL 508 rated value**<br>~~a~~<br>~~ey~~||50 A<br>~~a~~<br>~~ey~~|
|Electrical Safety<br>~~ey~~|||
|**touch protection on the front according to IEC 60529**<br>~~ey~~||finger-safe, for vertical contact from the front<br>~~ey~~|
|**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|
|**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 A for industrial environment<br>~~re~~|
|**Short-circuit protection, design of the fuse link**|||
|manufacturer's article number|||
|● of full range R fuse link for semiconductor protection at<br>NH design usable||3NE1803-0; These fuses have a smaller rated current than the semiconductor<br>relays|
|● of back-up R fuse link for semiconductor protection at NH<br>design usable||3NE8018-1|
|● of back-up R fuse link for semiconductor protection at<br>cylindrical design 14 x 51 mm usable||3NC1450; 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 22 x 58 mm usable||3NC2250; These fuses have a smaller rated current than the semiconductor<br>relays|
|manufacturer's article number of the gG fuse at NH design<br>usable|||
|● up to 460 V<br>~~ee~~||3NA3807-6; These fuses have a smaller rated current than the semiconductor<br>relays<br>~~ee~~|
|● up to 600 V<br>~~ee~~||3NA3805-6; These fuses have a smaller rated current than the semiconductor<br>relays<br>~~ee~~|
|**Approvals Certificates**<br>~~ee~~|||
|**Environment**<br>~~ee~~|**General Product Approval**<br>~~ee~~||



- manufacturer's article number of the gG fuse at NH design usable 

● up to 460 V 3NA3807-6; These fuses have a smaller rated current than the semiconductor relays ● up to 600 V 3NA3805-6; These fuses have a smaller rated current than the semiconductor relays **Approvals Certificates** ~~ee~~ 

**Environment** Environmental Confirmations **General Product Approval** 

**General Product Approval EMV Test Certificates other** 

3RF22551AC45 Page 3/5 

Subject to change without notice © Copyright Siemens 

6/2/2026 

- Type Test Certific ates/Test Report 

Confirmation 

Confirmation 

Miscellaneous 

## **other** 

QC PASS ~~a~~ **Further information 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=3RF2255-1AC45 **Cax online generator** https://support.automation.siemens.com/WW/CAXorder/default.aspx?lang=en&mlfb=3RF2255-1AC45 **Service&Support (Manuals, Certificates, Characteristics, FAQs,...)** https://support.industry.siemens.com/cs/ww/en/ps/3RF2255-1AC45 **Image database (product images, 2D dimension drawings, 3D models, device circuit diagrams, EPLAN macros, ...)** https://www.automation.siemens.com/bilddb/cax_de.aspx?mlfb=3RF2255-1AC45&lang=en 

3RF22551AC45 Page 4/5 

Subject to change without notice © Copyright Siemens 

6/2/2026 

**==> picture [497 x 469] intentionally omitted <==**

**----- Start of picture text -----**<br>
-Q<br>fT [ | [ f 7 7 fT TT fT fT tT fT ft tT tT tT tT tT Ty, 250 a a a<br>a ve Se _|<br>poa [ f j fjAfApp fp pp PP OA 200 a aCsa Rthha<br>PotAa a pya a yta pyadareeGG ><  Oee 150 a eS aas eea 0,050,070,1 K/WK/WK/W<br>aaa a eeee ee a 0,140,2 K/WK/W<br>aaa a a eeaa Ooee ee 100 aaSSa i ee a 0,280,4 K/WK/W<br>Aa a a SOeeeeOOO a a| a a ss 0,55 K/W<br>p [| {| | ft ft | yap tp 0,8 K/W<br>| [ ft yy fT par Pp a | Or 1,5 K/W<br>|aa| fomaa a cea tT aPeOOee 50 ———S—_—_S_aee —_|i 1,12 K/WK/W<br>a es a 3 K/W<br>entA atT | att Oe PP 0 aPoA SOYO 4 K/W<br>5 15 25 35 45 55 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>+ -<br>1/L1 3/L2 5/L3 A1 A2<br>1 2 3<br>T T T<br>2/ 4/ 6/<br> (W)  M (A)I e<br>P<br> (W)<br> M<br>P<br>/ Modulverlustleistung<br>loss<br>power<br>Module<br>**----- End of picture text -----**<br>


**last modified:** 

4/4/2026 

3RF22551AC45 Page 5/5 

Subject to change without notice © Copyright Siemens 

6/2/2026