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Siemens 3RH1921-1CA01
by Siemens
Read verified buyer reviews ↓OverviewThe Siemens 3RH1921-1CA01 SIRIUS Auxiliary Contact Block is a vital component for industrial automation, expertly designed to augment and optimize the control capabilities of SIRIUS contactors. This high-performance module provides a crucial interface for intricate control circuits, ensuring smooth operation and increased adaptability. With its robust construction and precise function, the 3RH1921-1CA01 enables dependable electrical switching, making it an essential asset for applications ranging from motor control to advanced process automation. Its intelligent front-mounting design simplifies installation and integration, reducing downtime and maximizing operational efficiency in demanding industrial settings. Crafted for engineers and technicians who require precision and longevity, this Siemens auxiliary contact block integrates seamlessly into existing SIRIUS systems, immediately boosting your control capacities. Experience the assurance that comes with utilizing authentic Siemens components, recognized for their unwavering quality and lasting dependability.Key Features Versatile 1 Normally Open (NO) + 1 Normally Closed (NC) Contacts: Offers extensive compatibility and adaptability for complex control circuit expansion and signal switching. Optimized Front Mounting Design: Enables swift, secure, and tool-free installation directly onto SIRIUS contactors, reducing setup time and effort. Precision Electrical Control: Guarantees consistent and reliable switching operations, minimizing errors and improving system uptime. Compact & Modular Form Factor: Maximizes panel space, allowing for efficient control cabinet design without compromising functionality. Industrial-Grade Durability & Longevity: Constructed from premium materials to endure harsh industrial conditions, ensuring extended operational life and reduced maintenance. Seamless Integration with SIRIUS Ecosystem: Engineered to function perfectly within the Siemens SIRIUS family, delivering a cohesive and intelligent automation solution. Enhanced Safety & Compliance: Adheres to strict IEC and industrial safety standards, providing a secure and compliant solution for essential applications. Technical Specifications Product Type: SIRIUS Auxiliary Contact Block Part Number: 3RH1921-1CA01 Number of Contacts: 1 Normally Open (NO) + 1 Normally Closed (NC) Mounting Type: Front Mounting on SIRIUS Contactors Switching Capacity: Specifically engineered for low-voltage control circuits, ensuring optimal performance and protection. Protection Rating: IP20 (Suitable for control cabinet installations, protecting against solid objects larger than 12.5mm) Compliance: Fully compliant with international IEC and relevant industrial safety standards, guaranteeing reliable and safe operation. Brand: Siemens Series: SIRIUS Applications Advanced Industrial Automation Systems: Provides crucial auxiliary switching functions for complex control sequences in manufacturing and processing plants. Comprehensive Motor Control Panels: Expands contactor capabilities in motor starter circuits, enabling sophisticated control and feedback mechanisms. Precision Process Control Systems: Supports accurate signal switching and interlocking functions within automated processes, enhancing overall system reliability. Building Management Systems (BMS): Facilitates control and monitoring of various building functions, including HVAC and lighting systems, through integrated automation. Energy Distribution & Management: Utilized in switchgear and control panels for auxiliary functions in power distribution and energy management applications. Specialized Machine Control: Ideal for custom machinery where precise and reliable auxiliary contacts are essential for operational safety and efficiency. Why ChooseBenefit from Siemens' renowned engineering and manufacturing excellence, ensuring exceptional quality and performance for your industrial control needs.Order NowUpgrade your industrial control systems with the Siemens 3RH1921-1CA01 SIRIUS Auxiliary Contact Block. Contact us today to place your order and ensure reliable performance and enhanced efficiency in your operations.FAQWhat is the primary function of the Siemens 3RH1921-1CA01?The Siemens 3RH1921-1CA01 is an auxiliary contact block designed to expand and optimize the control functions of SIRIUS contactors within industrial automation systems.How does the front-mounting design benefit installation?The optimized front-mounting design allows for quick, secure, and tool-free installation directly onto SIRIUS contactors, significantly reducing installation time and effort.What types of contacts does this auxiliary contact block feature?This auxiliary contact block features one Normally Open (NO) and one Normally Closed (NC) contact, offering versatility for various control circuit expansions and signal switching applications.Is the Siemens 3RH1921-1CA01 compliant with industry standards?Yes, it is fully compliant with international IEC and relevant industrial safety standards, ensuring reliable and safe operation in critical applications.In what applications is this product typically used?It is commonly used in advanced industrial automation systems, motor control panels, precision process control systems, building management systems, energy distribution, and specialized machine control.
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Siemens 3RH1921-1CA01
Overview
This is a genuine Siemens component from the SIRIUS Contactors family. PalmPartsSolution stocks it in new, refurbished, and surplus condition with tested warranty and same-day shipping on in-stock units.
Whether you are sourcing a like-for-like replacement for an existing installation, an emergency spare to keep a line running, or a qualified part for a new build, our team can confirm availability, revision, and lead time before you order.
Key Features
- Genuine Siemens catalog part
- Tested before shipment
- Backed by PalmPartsSolution warranty
- Cross-reference and revision assistance available
- Compatible with the broader Siemens automation ecosystem
- Engineered to integrate inside SIRIUS Contactors installations
Compatibility
When ordering, match the full catalog/part number, hardware revision, and firmware revision called out by your Siemens equipment. Where applicable, confirm:
- Input/output voltage and current rating
- Communication protocol and network role
- Mounting form factor and footprint
- Operating temperature, humidity, and IP rating
- Required certifications (UL, CE, ATEX, marine, etc.)
Not sure which revision you need? Send us the catalog number on the nameplate and we will confirm the correct match.
Replacement Information
Three ways to source this part through PalmPartsSolution:
- Exact replacement — same Siemens catalog number, new or refurbished, tested and warrantied
- Form-fit-function equivalent — alternate revision or build that drops in without code changes
- Engineered migration — current-generation Siemens platform with documented conversion notes for the SIRIUS Contactors family
Contact our engineering team if you need help choosing between these tracks.
Technical Specifications
- Product Type: SIRIUS Auxiliary Contact Block
- Part Number: 3RH1921-1CA01
- Number of Contacts: 1 Normally Open (NO) + 1 Normally Closed (NC)
- Mounting Type: Front Mounting on SIRIUS Contactors
- Switching Capacity: Specifically engineered for low-voltage control circuits, ensuring optimal performance and protection.
- Protection Rating: IP20 (Suitable for control cabinet installations, protecting against solid objects larger than 12.5mm)
- Compliance: Fully compliant with international IEC and relevant industrial safety standards, guaranteeing reliable and safe operation.
- Brand: Siemens
- Series: SIRIUS
Applications
- Advanced Industrial Automation Systems: Provides crucial auxiliary switching functions for complex control sequences in manufacturing and processing plants.
- Comprehensive Motor Control Panels: Expands contactor capabilities in motor starter circuits, enabling sophisticated control and feedback mechanisms.
- Precision Process Control Systems: Supports accurate signal switching and interlocking functions within automated processes, enhancing overall system reliability.
- Building Management Systems (BMS): Facilitates control and monitoring of various building functions, including HVAC and lighting systems, through integrated automation.
- Energy Distribution & Management: Utilized in switchgear and control panels for auxiliary functions in power distribution and energy management applications.
- Specialized Machine Control: Ideal for custom machinery where precise and reliable auxiliary contacts are essential for operational safety and efficiency.
Why Choose the 3RH1921-1CA01?
Benefit from Siemens' renowned engineering and manufacturing excellence, ensuring exceptional quality and performance for your industrial control needs.
Availability & Shipping
- ▸In stock: 3RH1921-1CA01 ready for immediate dispatch from our Florida warehouse.
- ▸Free USA shipping: FedEx Priority (2–5 business days) and UPS Ground (3–5 business days). Expedited options available at checkout.
- ▸Worldwide delivery: FedEx International Priority (1–5 days), UPS International Priority (3–5 days), and USPS International (5–10 days) — rates calculated at checkout.
- ▸Bulk pricing: Volume discounts on request — contact our sales team for quantity quotes.
- ▸Buy with confidence: Every 3RH1921-1CA01 ships with a 1-Year PALM Parts warranty and a 30-day return window.
Frequently Asked Questions — Siemens
Machine down? We ship parts the same day.
New, surplus, and refurbished Siemens inventory in stock. Request a quote or speak directly with an automation specialist for emergency sourcing.
Related Siemens resources
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Independent Supplier Notice
PALM Parts Solution operates as an independent industrial automation supplier and is not an authorized distributor or affiliate of any listed manufacturer or brand name. Manufacturer trademarks and product names are used solely for identification purposes. Original manufacturer warranties do not apply. All products sold by PALM Parts are backed by our own 1-year warranty.
Product Condition & Firmware
All products are sold as new unless stated otherwise. Original manufacturer packaging may show signs of handling, storage, or shelf wear. Date codes and series may vary from current factory production. PALM Parts does not guarantee the presence, version, or compatibility of any firmware on PLC or automation products.