Siemens 3RT6028-1AL20 Industrial Heavy Duty AC Contactor 230VAC 38A 3NO

The Siemens 3RT6028-1AL20 is a robust, heavy-duty industrial AC contactor designed for demanding applications. This 230VAC, 38A contactor features three normally open (3NO) poles, ensuring reliable power switching for motor control and other high-current loads. Its compact design and superior switching capacity make it a preferred choice for seamless integration into various industrial automation systems, offering exceptional durability and operational efficiency.

Product Specifications

| Feature                     | Specification                                  |

| :-------------------------- | :--------------------------------------------- |

| Manufacturer                | Siemens                                        |

| Product Number              | 3RT6028-1AL20                                  |

| Type                        | Industrial Heavy Duty AC Contactor             |

| Coil Voltage                | 230VAC                                         |

| Rated Operational Current (AC-3) | 38A                                            |

| Number of Poles             | 3                                              |

| Pole Configuration          | 3 Normally Open (3NO)                          |

| Mounting Type               | DIN Rail / Screw Mount                         |

| Terminal Type               | Screw Terminals                                |

| Ambient Operating Temperature | -25°C to +60°C                                 |

| IP Rating                   | IP20 (with cover)                              |

| Compliance                  | IEC/EN 60947-4-1, IEC/EN 60947-5-1             |

Core Features & Market Positioning

The Siemens 3RT6028-1AL20 distinguishes itself through its inherent Siemens quality, a hallmark of reliability in industrial control components. This 38A contactor is engineered for extended operational life, even under frequent switching cycles and challenging environmental conditions, a critical factor for uptime in manufacturing and process industries. Its market positioning is firmly rooted in providing dependable, high-performance motor control solutions where failure is not an option. The robust construction minimizes wear and tear, translating to lower maintenance costs and greater operational predictability compared to lighter-duty alternatives. This focus on durability and performance makes the 3RT6028-1AL20 a competitive offering for applications demanding unwavering reliability.

Key Application Scenarios

This Siemens 3RT6028-1AL20 contactor is exceptionally well-suited for controlling and switching three-phase motors in industrial settings. Common applications include HVAC systems, pump control, conveyor systems, and machine tool operations where the 38A current rating is appropriate. Its 230VAC coil voltage allows for straightforward integration into standard control circuits found across numerous manufacturing plants and building management systems. Facilities requiring precise and safe motor management, particularly those subject to rigorous operational demands and compliance standards, will find this 3RT6028-1AL20 an ideal component.

Practical System Integration Guidance

Integrating the Siemens 3RT6028-1AL20 into a control panel is typically achieved via standard 35mm DIN rail mounting or direct screw mounting, facilitated by the integrated mounting lugs. Wiring involves connecting the main power circuit conductors to the power terminals and the control circuit to the coil terminals (typically A1 and A2 for the 230VAC coil). For safety, always ensure power is de-energized before commencing any wiring. The contactor's auxiliary contacts, if utilized, can be wired to provide status feedback to a PLC or other control system, enabling monitoring of the contactor's operational state. It's crucial to adhere to local electrical codes and standards during installation.

Operation and Risk Mitigation

Proper operation of the Siemens 3RT6028-1AL20 involves applying the correct 230VAC to the coil terminals to actuate the switching mechanism. The 3NO contacts will close, establishing power to the connected load, typically a motor. Risk mitigation is paramount; users must ensure the contactor is appropriately sized for the load to prevent overheating and premature failure. Isolation mechanisms, such as fuses or circuit breakers, should be installed upstream of the contactor to protect against overcurrent and short circuits. Regular visual inspection for signs of wear or damage, and periodic testing of coil and contact resistance, are recommended practices to maintain safe and reliable operation.

Scalability & Long-Term Value

The Siemens 3RT6028-1AL20 offers excellent long-term value due to its robust construction and Siemens' commitment to component longevity. While this specific model is a standalone unit, its integration into larger Siemens automation platforms, such as SIMATIC PLCs, allows for expanded system capabilities and future upgrades. Compatibility with other Siemens industrial components ensures a cohesive and scalable system architecture. For facilities embracing Industry 4.0 initiatives, the 3RT6028-1AL20 can be part of a system that utilizes intelligent gateways or I/O modules to provide remote monitoring and diagnostics, contributing to predictive maintenance strategies and overall operational efficiency.

Frequently Asked Questions (FAQs)

What is the maximum load this Siemens 3RT6028-1AL20 can handle?

The Siemens 3RT6028-1AL20 is rated for 38A under AC-3 motor control application category. This rating signifies its capability for switching three-phase induction motors during normal operation.

It can also handle different current ratings for other applications, like AC-1 for resistive loads. Always consult the full datasheet for complete specifications.

Exceeding these ratings can lead to overheating, contact welding, or premature failure of the contactor.

How do I wire the Siemens 3RT6028-1AL20 for a 3-phase motor?

Connect the incoming three-phase power lines (L1, L2, L3) to the main power terminals of the contactor. Then, connect the outgoing motor leads (T1, T2, T3) from the other side of these main terminals.

The coil voltage, 230VAC, is applied to terminals A1 and A2 to energize and close the contacts. Ensure correct polarity and voltage for the coil.

Utilize appropriate wire gauges and ensure all connections are tight to prevent resistance buildup and ensure safe operation.

What is the lifespan of a Siemens 3RT6028-1AL20 contactor?

The lifespan is extensive, often rated in millions of mechanical and electrical switching cycles. This depends heavily on the application load and switching frequency.

Siemens contactors are built for durability, offering reliable performance under demanding industrial conditions for many years.

Regular maintenance and adherence to operational specifications will maximize the service life of the 3RT6028-1AL20.

Can the Siemens 3RT6028-1AL20 be used with DC loads?

This specific model, 3RT6028-1AL20, is designed for AC (Alternating Current) loads. Using it with DC loads is not recommended and can lead to malfunction or damage.

For DC applications, Siemens offers specific DC contactors with different contact designs and arc suppression. Ensure you select the correct type for your load.

Refer to the product documentation or contact Siemens support for guidance on suitable contactors for DC circuits.

What are the typical environments for the 3RT6028-1AL20?

It is designed for industrial environments, capable of operating within a wide temperature range of -25°C to +60°C.

Protection against dust and moisture is provided via its enclosure, typically rated IP20 with a cover, suitable for most manufacturing floors.

Consider additional enclosures if the contactor will be exposed to extreme conditions, such as high humidity or corrosive atmospheres.

Does the 3RT6028-1AL20 have auxiliary contacts?

The base 3RT6028-1AL20 typically comes with a standard configuration of main poles. Check the specific product variant or datasheet for included auxiliary contacts.

Auxiliary contacts are often available as add-on modules for these contactors, allowing for signaling, interlocking, or control purposes.

These can be front-mounted or side-mounted, providing flexibility for system integration and monitoring.

How can I protect the Siemens 3RT6028-1AL20 from overloads?

Overload protection is typically provided by a separate device, such as a Siemens overload relay (e.g., 3RU series) connected in series with the contactor.

Alternatively, a circuit breaker with appropriate thermal and magnetic tripping characteristics can offer both short-circuit and overload protection for the motor circuit.

The contactor itself is not an overload protection device; it is designed to switch power under normal and short-circuit conditions when protected by external devices.

What kind of coil voltage does the 3RT6028-1AL20 use?

This specific model, 3RT6028-1AL20, is configured with a 230VAC (Volts Alternating Current) coil voltage. This is a standard industrial control voltage.

Ensure that the control circuit power supply matches this 230VAC requirement for proper operation of the contactor's coil.

Incorrect coil voltage can prevent the contactor from energizing or cause it to overheat and fail.

Where can I find the datasheet for the Siemens 3RT6028-1AL20?

The official datasheet can be found on the Siemens Industry Online Support (SIOS) portal. You can search for the product number 3RT6028-1AL20 directly on their website.

Distributor websites that sell Siemens products often provide direct links to datasheets or product documentation as well.

Always refer to the official datasheet for the most accurate and comprehensive technical specifications, dimension drawings, and application notes.

What are the dimensions of the Siemens 3RT6028-1AL20?

The dimensions are generally compact for industrial contactors of this rating, allowing for efficient use of space in control panels.

Typical dimensions would be around 45mm in width, 75mm in height, and 120mm in depth, but always verify with the official datasheet.

These measurements are important for panel layout planning and ensuring sufficient clearance for wiring and heat dissipation.