Siemens 3RT6027-1AN20 High Power 3RT60 Control Contactor 220VAC 32A 3NO

The Siemens 3RT6027-1AN20 is a robust 3RT60 control contactor designed for demanding industrial applications, offering reliable switching of high power loads up to 32A at 220VAC. This contactor features three normally open (3NO) poles, ensuring straightforward circuit configuration for motor control and power switching tasks. Its compact design and straightforward terminal connections facilitate quick and efficient integration into control panels, while its robust construction guarantees longevity even in harsh environments. The Siemens 3RT60 series is engineered for performance and dependability, making the 3RT6027-1AN20 a cornerstone component for many industrial automation systems.

Product Specifications

| Feature                  | Specification                                     |

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

| Product Type             | Control Contactor                                 |

| Series                   | 3RT60                                             |

| Model Number             | 3RT6027-1AN20                                     |

| Rated Operational Voltage | 220VAC                                            |

| Rated Operational Current | 32A                                               |

| Number of Poles          | 3                                                 |

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

| Auxiliary Contacts       | Not specified in this model (typically orderable) |

| Mounting Type            | Rail Mount (Standard)                             |

| Enclosure Type           | Open (typically installed within a panel)         |

| Operating Temperature    | Varies by specific environmental conditions       |

| Compliance               | CE, UL, CSA (typical for Siemens industrial)      |

Core Features & Market Positioning

The Siemens 3RT6027-1AN20 distinguishes itself through its inherent reliability and straightforward operational design, key attributes highly valued in industrial settings where uptime is paramount. As part of Siemens' established industrial control portfolio, this contactor benefits from extensive research and development, ensuring it meets stringent performance standards. Its 3NO configuration is ideal for direct motor starting or switching of resistive loads, simplifying wiring compared to contactors with auxiliary contacts. The market positioning of this contactor emphasizes its role as a dependable, cost-effective solution for general-purpose power switching, directly competing with other major industrial control manufacturers by offering robust performance and the assurance of Siemens' global support and quality reputation.

Key Application Scenarios

This Siemens 3RT6027-1AN20 contactor is frequently employed in industrial motor control circuits, particularly for direct-on-line (DOL) starting of three-phase motors where precise and robust switching is required. Its 32A rating makes it suitable for medium-sized industrial machinery, including pumps, fans, conveyors, and compressors, across various sectors such as manufacturing, water treatment, and building automation. The 220VAC coil voltage aligns with common control power supplies in many regions, simplifying integration into existing electrical infrastructure. End-users often search for this product when specifying components for new panel builds or when replacing aging or failed contactors in existing systems, prioritizing durability and consistent performance.

Practical System Integration Guidance

Integrating the Siemens 3RT6027-1AN20 into a control system is typically straightforward due to its standard rail-mounting design and clearly labeled terminals. For typical motor control applications, the incoming power lines (L1, L2, L3) are connected to the main power terminals, and the motor leads are connected to the load terminals. The 220VAC control coil is energized via a control circuit to engage the contactor, switching the main power contacts. Proper wire sizing according to local electrical codes and the load current is critical to prevent overheating and ensure safe operation. Overload relays, such as Siemens' 3RU series, are commonly wired in series with the control circuit of the contactor to provide motor protection against overcurrent conditions.

Operation and Risk Mitigation

The Siemens 3RT6027-1AN20 operates by utilizing a 220VAC coil to generate a magnetic field that closes the main power contacts, thereby completing the circuit to the load. Upon de-energization of the coil, a spring mechanism opens the contacts, interrupting power flow. Safe operation is paramount; therefore, it's essential to ensure the contactor is correctly rated for the load and that appropriate overcurrent protection, such as a thermal overload relay or a circuit breaker, is installed in series. Users should always follow lockout/tagout procedures during installation, maintenance, or troubleshooting to prevent accidental energization. While specific fault codes are not inherent to the contactor itself, common issues like coil failure or contact welding can be diagnosed by checking for proper coil voltage and examining the main contacts for signs of excessive arcing or wear.

Scalability & Long-Term Value

The Siemens 3RT6027-1AN20 offers significant long-term value through its compatibility with a wide range of Siemens industrial automation components and its robust, reliable design that minimizes maintenance requirements. While this specific model is a standalone contactor, its integration into larger systems can be enhanced by pairing it with Siemens programmable logic controllers (PLCs) or human-machine interfaces (HMIs) for advanced control and monitoring. For applications requiring more sophisticated control or diagnostics, Siemens offers advanced contactor variants or solid-state relays that can provide data feedback and diagnostics capabilities essential for IIoT and Industry 4.0 initiatives. The availability of spare parts and Siemens' extensive global support network further ensures the longevity and maintainability of systems employing this contactor.

Frequently Asked Questions

What is the main function of the Siemens 3RT6027-1AN20 contactor?

This contactor acts as an electrically operated switch for high-power circuits. It is designed to safely open and close circuits, primarily for starting and stopping electric motors. Its 3NO configuration is ideal for direct motor control applications.

Can this contactor be used for AC and DC loads?

The Siemens 3RT6027-1AN20 is specifically designed for AC loads, with a 220VAC coil voltage and a 32A AC current rating. Using it for DC loads is not recommended and could lead to premature failure or hazardous conditions.

How do I wire the Siemens 3RT6027-1AN20 for a simple motor start application?

Connect the three incoming power lines (L1, L2, L3) to the upper terminals and the three motor leads to the corresponding lower terminals. The 220VAC coil is controlled by a separate circuit to energize and close these main contacts.

What type of overload protection is recommended with this contactor?

A thermal overload relay, such as a Siemens 3RU series, is highly recommended. It should be wired in series with the control circuit of the contactor to provide accurate motor protection against overcurrents.

What is the significance of the 3NO (3 Normally Open) configuration?

A 3NO configuration means that when the contactor is de-energized, all three main poles are open, interrupting the circuit. When the coil is energized, these three poles close simultaneously, completing the circuit for a three-phase load.

Is the Siemens 3RT6027-1AN20 suitable for frequent switching cycles?

Yes, Siemens 3RT contactors are built for industrial duty and can handle a significant number of switching cycles. However, extremely high switching frequencies may require specific considerations or alternative solutions like solid-state relays.

What are the typical installation requirements for this contactor?

It is designed for standard 35mm DIN rail mounting. Ensure adequate ventilation around the contactor when installed within an enclosure to prevent overheating and maintain optimal performance.

Where can I find the detailed dimensions and mounting instructions?

Detailed dimensions and mounting instructions can be found in the official Siemens technical documentation or datasheet for the 3RT6027-1AN20. These are usually available on the Siemens industry online portal.

What is the purpose of the coil voltage (220VAC)?

The 220VAC coil voltage is the input required to energize the electromagnet within the contactor. This electromagnetic force causes the main power contacts to close, allowing current to flow to the load.

How can I verify if the contactor coil is functioning correctly?

You can measure the voltage across the coil terminals when the control signal is applied. If the correct voltage (220VAC) is present but the contactor does not engage, the coil may be faulty or there might be an issue with the control circuit.