# Residual Current Unit, for 5SY Series Circuit Breaker

![Product image](https://novapart.co/image/farnell:3474865/)

**URL**: https://novapart.co/products/5SM2121-6/residual-current-unit-for-5sy-series-circuit
**SKU**: 5SM2121-6
**Manufacturer**: SIEMENS
**Category**: Circuit Protection || Circuit Breakers || Circuit Breaker Accessories
**Price**: €95.1500
**Stock**: 10+

## Specifications

| Parameter | Value |
|---|---|
| Product Range | SENTRON Series |

## Datasheet

📄 [Download PDF](https://novapart.co/datasheet/farnell:3474865/)

**5SM2121-6** 

**Data sheet** 

RC unit for 5SY, 2-pole, type A, In: 16 A, 10 mA, Un AC: 230 V 

|il<br>Figure similar|RC unit for 5SY, 2-pole, type A, In: 16 A, 10 mA, Un AC: 230 V<br>|
|---|---|
|**Model**<br>~~|~~||
|**product brand name**<br>~~|~~|SENTRON<br>~~|~~|
|**product designation**|RCD-unit|
|**design of theproduct**|Instantaneous|
|**product type designation**|5SM2|
|**product version**|for 5SY|
|**General technical data**<br>~~|~~||
|**number ofpoles**<br>~~|~~|2<br>~~|~~|
|**design ofpole**|2poles|
|**size of installation devices according to DIN 43880**|1|
|**touch protection against electrical shock according to EN**<br>**50274**|Finger and back-of-hand safe|
|**mechanical service life(operating cycles) typical**|10 000|
|**overvoltage category**|III|
|**degree of pollution**|2|
|**Voltage**<br>~~|~~||
|**type of voltage of the operating voltage**<br>~~|~~|AC<br>~~|~~|
|insulation voltage(Ui)rated value|460 V|
|surge voltage resistance rated value|4 000 V|
|**tripping fault current rated value**|10 mA|
|||
|**● operational current**||
|**— at 40 °C rated value**|14.9 A|
|— at 45 °C rated value|14.88 A|
|— at 50 °C rated value|14.4 A|
|— at 55 °C rated value|13.92 A|
|— at 60 °C rated value|13.6 A|
|— at 65 °C rated value|13.28 A|
|— at 70 °C rated value|12.8 A|
|**● operational current at AC rated value**|16 A|
|**residual current type**|A|
|**surge current resistance rated value**|1 kA|
|**supply voltage**||
|● at AC|230 V|
|● for testingequipment minimum|195 V|
|**value range of the supply voltage frequency**|50 Hz|
|**value range of the operating frequency**<br>~~OO~~|50 Hz|
|**Protection class**<br>~~OO~~<br>~~—CSC“‘:CCNCSC:CSC:sC‘iés~~||



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|**protection class IP**|**protection class IP**|IP20, if the distribution board is installed, with connected conductors|
|---|---|---|
|**protection function false tripping**<br>~~re~~||Yes<br>~~re~~|
|**Dissipation**|||
|**power loss[W]**|||
|● for rated value of the current at AC in hot operating state<br>perpole||2.5 W|
|● maximum||5 W|
|**Product details**<br>~~a~~|||
|**product feature OFF-delay time adjustable**<br>~~a~~||No|
|**product feature rated fault current adjustable**<br>~~re~~||No<br>~~re~~|
|**product feature sealable**<br>~~re~~||No<br>~~re~~|
|**Connections**|||
|**connectable conductor cross-section solid**|||
|● minimum||1.5 mm²|
|● maximum||25 mm²|
|**connectable conductor cross-section stranded**|||
|● minimum||1.5 mm²|
|● maximum||25 mm²|
|**tightening torque with screw-type terminals**|||
|● minimum||2.5 N·m|
|● maximum<br>~~re~~||3 N·m<br>~~re~~|
|**position of power supply cord**<br>~~re~~||top or bottom<br>~~re~~|
|**Mechanical Design**|||
|**height**||90 mm|
|**width**||36 mm|
|**depth**||70 mm|
|**installation depth**||70 mm|
|**number of modular width units**||2|
|**fastening method**||DIN rail|
|**mounting position**<br>~~re~~||any<br>~~re~~|
|**Net Weight**<br>~~re~~||202g<br>~~re~~|
|**Environmental conditions**|||
|**ambient temperature during operation**|||
|● minimum||-25 °C|
|● maximum||45 °C|
|**ambient temperature during storage**|||
|● minimum||-40 °C|
|● maximum||75 °C|
|**number of test cycles for environmental testing according**<br>**to IEC 60068-2-30**<br>~~a~~||28<br>~~a~~|
|**Certificates**<br>~~a~~|||
|**reference code according to IEC 81346-2**<br>~~a~~||F<br>~~a~~|
|**Approvals Certificates**<br>~~a~~|||
|**Environment**<br>~~a~~|**General Product Approval**<br>~~a~~||



**Further information** ~~ee~~ **Information on the packaging** 

5SM21216 Page 2/5 

Subject to change without notice © Copyright Siemens 

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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/lowvoltage/catalogs 

**Industry Mall (Online ordering system)** https://mall.industry.siemens.com/mall/en/en/Catalog/product?mlfb=5SM2121-6 

**Service&Support (Manuals, Certificates, Characteristics, FAQs,...)** https://support.industry.siemens.com/cs/ww/en/ps/5SM2121-6 

**Image database (product images, 2D dimension drawings, 3D models, device circuit diagrams, ...)** https://www.automation.siemens.com/bilddb/cax_en.aspx?mlfb=5SM2121-6 

## **CAx-Online-Generator** 

https://www.siemens.com/cax 

## **Tender specifications** 

https://www.siemens.com/specifications 

## **Characteristic curves** 

https://curves.simaris.siemens.com/curves/<mmp_prod_noCOMP="HAUPT"></mmp_prod__no> 

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**last modified:** 

4/12/2025 

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Subject to change without notice © Copyright Siemens 

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Subject to change without notice © Copyright Siemens 

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## Links

- [View this product on Novapart](https://novapart.co/products/5SM2121-6/residual-current-unit-for-5sy-series-circuit)
- [Request a quote for this part](https://novapart.co/quote/)
- [Supplier page](https://es.farnell.com/siemens/5sm2121-6/circuit-breaker-accessories/dp/3474865)
---

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