3UG4851-2AA40

**3UG4851-2AA40** 

**Data sheet** 

!!! product phase-out !!! the preferred successor is 3UG5851-2AA40 digital monitoring relay speed monitoring for IO-Link from 0.1 to 2200 r/min overshoot and undershoot ON-delay time tripping delay time hysteresis 0.1 to 99 r/min 1 changeover contact, spring-loaded connection system 

|**product brand name**|SIRIUS|
|---|---|
|**product designation**|Speed monitoringrelaywith digital setting|
|**product type designation**|3UG4|
|**General technical data**<br>~~|~~||
|**product function**|RPM monitoringrelay|
|**design of the display**|LCD|
|||
|● Apparentpower consumption at DC||
|— at 24 V maximum|4 VA|
|**insulation voltage**||
|**● for overvoltage category III according to IEC 60664**||
|— with degree ofpollution 2 rated value|300 V|
|**degree ofpollution**|2|
|type of voltage of the control supplyvoltage|DC|
|**surge voltage resistance rated value**|4 kV|
|**protection class IP**||
|● of the enclosure|IP40|
|● of the terminal|IP20|
|**shock resistance according to IEC 60068-2-27**|sinusoidal half-wave 15g/ 11 ms|
|**vibration resistance according to IEC 60068-2-6**|1 ... 6 Hz: 15 mm, 6 ... 500 Hz: 2g|
|**mechanical service life(operating cycles) typical**|10 000 000|
|electrical endurance(operatingcycles)at AC-15 at 230 V typical|100 000|
|**thermal current of the switching element with contacts**|5 A|
|**maximum**||
|**reference code according to IEC 81346-2**|K|
|**relative repeat accuracy**|1 %|
|**Substance Prohibitance(day/month/year)**|05/01/2012|
|**SVHC substance name**|Lead CAS-No. 7439-92-1|
||Lead monoxide (lead oxide) CAS-No. 1317-36-8|
||2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one CAS-No. 71868-|
||10-5|
||Melamine CAS-No. 108-78-1|
||6,6'-di-tert-butyl-2,2'-methylenedi-p-cresol CAS-No. 119-47-1|



||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<br>6,6'-di-tert-butyl-2,2'-methylenedi-p-cresol CAS-No. 119-47-1|
|---|---|
|**Net Weight**|0.144 kg|
|**Product Function**<br>~~|~~||
|**product function**||
|● standstill monitoring|No|
|● rotation speed monitoring|Yes|
|● error memory|Yes|
|●galvanic isolation|Yes|
|● adjustable open/closed-circuit current principle|Yes|



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|● external reset|Yes|
|---|---|
|● auto-RESET|Yes|
|● manual RESET|Yes|
|suitabilityfor use safety-related circuits|No|
|**Control circuit/ Control**||
|**control supply voltage at DC rated value**|24 V|
|**operating range factor control supply voltage rated value at**<br>**DC**||
|● initial value|0.75|
|● full-scale value|1.25|
|**Measuring circuit**||
|**adjustable operating delay time**|0 ... 99.9 s|
|**adjustable response delay time**||
|● when starting|0 ... 999.8 s|
|● with lower or upper limit violation|0 ... 999.8 s|
|**accuracy of digital display**|+/- 1 Digit|
|**Precision**||
|**relative metering precision**|10 %|
|**Communication/ Protocol**||
|protocol is supported IO-Linkprotocol|Yes|
|**IO-Link transfer rate**|COM2(38,4 kBaud)|
|**point-to-point cycle time between master and IO-Link**<br>**device minimum**|10 ms|
|**type of voltage supply via input/output link master**|Yes|
|**data volume**||
|● of the address range of the inputs with cyclical transfer<br>total|4 byte|
|● of the address range of the outputs with cyclical transfer<br>total|2 byte|
|**Auxiliary circuit**||
|number of NC contacts delayed switching|0|
|number of NO contacts delayed switching|0|
|number of CO contacts delayed switching|1|
|**operating frequency with 3RT2 contactor maximum**|5 000 1/h|
|**Inputs/ Outputs**||
|design of input feedback input|No|
|**number of outputs as contact-affected switching element**||
|● for signalingfunction||
|— instantaneous contact|0|
|— delayed switching|1|
|● safety-related||
|— delayed switching|0|
|— instantaneous contact|0|
|**number of outputs as contact-less semiconductor**<br>**switching element**||
|● for signalingfunction||
|— delayed switching|0|
|— instantaneous contact|0|
|● safety-related||
|— delayed switching|0|
|— instantaneous contact|0|
|**ampacity of the output relay at AC-15**||
|● at 230 V at 50/60 Hz|3 A|
|● at 250 V at 50/60 Hz|3 A|
|**ampacity of the output relay at DC-13**||
|● at 24 V|1 A|
|● at 110 V|0.2 A|
|● at 125 V|0.2 A|
|● at 230 V|0.1 A|
|● at 250 V|0.1 A|



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|**ampacity of the semiconductor output in SIO mode**|200 mA|
|---|---|
|**operational current at 17 V minimum**|5 mA|
|**continuous current of the DIAZED fuse link of the output**<br>**relay**|4 A|
|**Electromagnetic compatibility**||
|**conducted interference**||
|● due to burst accordingto IEC 61000-4-4|2 kV|
|● due to conductor-earth surge accordingto IEC 61000-4-5|2 kV|
|● due to conductor-conductor surge according to IEC<br>61000-4-5|1 kV|
|**field-based interference according to IEC 61000-4-3**|10 V/m|
|**electrostatic discharge according to IEC 61000-4-2**|6 kV contact discharge / 8 kV air discharge|
|**Galvanic isolation**||
|**galvanic isolation**||
|● between input and output|Yes|
|● between the outputs|No|
|● between the voltage supplyand other circuits|Yes|
|IEC 61508||
|SafetyIntegrityLevel(SIL)accordingto IEC 61508|without|
|Electrical Safety||
|**protection class IP on the front according to IEC 60529**|IP20|
|**Connections/ Terminals**||
|**product component removable terminal for auxiliary and**<br>**control circuit**|Yes|
|**type of electrical connection**|spring-loaded terminals|
|**type of connectable conductor cross-sections**||
|● solid|2x(0.25 ... 1.5 mm²)|
|● finelystranded with core endprocessing|2 x(0.25 ... 1.5 mm²)|
|● finelystranded without core endprocessing|2x(0.25 ... 1.5 mm²)|
|● for AWG cables solid|2x(24 ... 16)|
|● for AWG cables stranded|2x(24 ... 16)|
|**connectable conductor cross-section**||
|● solid|0.25 ... 1.5 mm²|
|● finelystranded with core endprocessing|0.25 ... 1.5 mm²|
|● finelystranded without core endprocessing|0.25 ... 1.5 mm²|
|**AWG number as coded connectable conductor cross**<br>**section**||
|● solid|24 ... 16|
|● stranded|24 ... 16|
|**Installation/ mounting/ dimensions**||
|**mounting position**|any|
|**fastening method**|screw and snap-on mounting|
|**height**|91 mm|
|**width**|22.5 mm|
|**depth**|103 mm|
|**required spacing**||
|● with side-by-side mounting||
|— forwards|0 mm|
|— backwards|0 mm|
|— upwards|0 mm|
|— downwards|0 mm|
|— at the side|0 mm|
|● forgroundedparts||
|— forwards|0 mm|
|— backwards|0 mm|
|— upwards|0 mm|
|— at the side|0 mm|
|— downwards|0 mm|
|● for liveparts||
|— forwards|0 mm|



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— backwards 0 mm — upwards 0 mm — downwards 0 mm — at the side 0 mm ~~|~~ **Ambient conditions** installation altitude at height above sea level maximum 2 000 m **ambient temperature** ● during operation -25 ... +60 °C ● during storage -40 ... +80 °C ● during transport -40 ... +80 °C ~~ee~~ **Approvals Certificates Environment General Product Approval** Environmental Confirmations ~~—~~ o mM BK ce **General Product ApEMV Test Certificates Maritime application proval** Manufacturer DeclaraSpecial Test CertificType Test Certifiction ate ates/Test Report ~~—~~ € & **other Railway** ~~Oo~~ Confirmation Confirmation Special Test Certificate QC PASS ~~OO—CtSC(‘™C‘CiésC~~ **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=3UG4851-2AA40 **Cax online generator** https://support.automation.siemens.com/WW/CAXorder/default.aspx?lang=en&mlfb=3UG4851-2AA40 **Service&Support (Manuals, Certificates, Characteristics, FAQs,...)** https://support.industry.siemens.com/cs/ww/en/ps/3UG4851-2AA40 **Image database (product images, 2D dimension drawings, 3D models, device circuit diagrams, EPLAN macros, ...)** https://www.automation.siemens.com/bilddb/cax_de.aspx?mlfb=3UG4851-2AA40&lang=en 

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**last modified:** 5/8/2026 

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