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Marvo Part ID: MV-27WI

£132.58 (ex. VAT)


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Commonly Asked Questions

What payment methods do you accept?

We accept card payments from all major credit, debit and Mastercard providers including Visa, American Express, Western Union, Paypal and bank transfers. Before you complete an order you will be prompted to input your payment details, at which point you can enter the relevant card information you wish to use for your transaction. If you are experiencing issues with your payment method then you can contact our team via email here. From there, you will be directed to the most relevant resource or person to help you complete your payment, get your order processed and ensure that your parts are on the way to your delivery address.


Is my order covered by a warranty?

Marvo provides a full 12-month warranty on all products, whatever the condition. For your peace of mind, all parts are ‘Marvo Approved’ which means that they have been tested and checked to ensure that they are in working condition. If you are unhappy with the part(s) you received and would like to request a return, you can do so by completing our quick and easy online form. Once we have received your Returns Request, a member of the team will be in touch to discuss this further with you. You can read more about our warranty policy here.


What countries can Marvo deliver to?

Marvo currently delivers to the United Kingdom (excluding Northern Ireland), the United States of America and Germany. If you cannot find your delivery address at checkout, this is most likely because Marvo does not currently deliver to this location. There are ongoing efforts to make Marvo accessible to a global market, keep your eyes peeled as our service expands to new locations. All orders are sold with a streamlined delivery process ensuring that you get your part, fast. Marvo is designed to offer you quick, easy and reliable access to critical components and uses well established global shipping services, including but not limited to DHL, UPS and FedEx.


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Is Marvo a credible parts supplier?

Marvo is a highly credible supplier of industrial automation parts and components with dedicated hubs around the world offering industry-leading products and services.  Marvo is committed to providing a quick, easy and reliable place to source your automation and control components. All purchases come as standard with a comprehensive 12-month return to base warranty meaning that, in just a few clicks, you can source critical parts more seamlessly than ever before. Click here to read an article on how Marvo is redefining convenience for automation and manufacturing professionals.


Have steps been taken to ensure quality control?

Marvo takes pride in product quality and has put several measures in place to assure high levels of quality standards. For your peace of mind, all parts have been ‘Marvo Approved’ which means that they have been tested and checked to ensure that they are in working condition. Redefine convenience and secure priority delivery on all parts along with a comprehensive 12-month warranty. This is the smart new way to buy automation and control components.


Peace of mind with every purchase


Marvo Approved

A seal of quality that ensures each part is fully inspected, every time. Purchase with confidence thanks to Marvo Approved.


Full warranty

All parts are covered by a comprehensive warranty. If something goes wrong, I’ll put it right.


Priority delivery

Advanced tracking and a streamlined delivery process ensure that you get your part, fast.


Committed to you

Engineered to ensure that you always have a quick, easy and reliable place to source automation and control components.

3RT1966-4G Product Description

The Siemens 3RT1966-4G is a robust box terminal designed to facilitate secure and reliable electrical connections for a range of Siemens contactors and overload relays. This terminal block is compatible with the 3RT1, 3RB2, and 3RW507 series, ensuring a versatile fit for various industrial applications. Crafted for durability, the 3RT1966-4G is engineered to support large conductor sizes up to 240 mm², making it suitable for high-power scenarios.

The design of the 3RT1966-4G allows for straightforward installation, providing a practical solution for maintenance and assembly processes. Its construction adheres to stringent product approvals and certifications, ensuring compliance with industry standards and regulations. This terminal block is an essential component for professionals seeking a reliable connection solution in industrial control systems. With its focus on quality and compatibility, the Siemens 3RT1966-4G represents a dependable choice for enhancing the operational efficiency of your electrical equipment.

Frequently Asked Questions

What is the purpose of a box terminal?

A box terminal is designed to facilitate secure and reliable electrical connections between conductors and the contactors or overload relays in industrial control systems. It ensures a stable connection that can handle the required current and voltage levels for the application.

Can this box terminal be used with any contactor size?

The Siemens 3RT1966-4G box terminal is specifically designed for use with contactors of size S10/S12 and overload relays such as the 3RB106.

What types of conductors can be connected to this box terminal?

This box terminal can accommodate solid or stranded conductors, as well as finely stranded conductors with core end processing. It supports a range of conductor cross-sections for both main and auxiliary contacts.

Is there a specific conductor cross-section range for the main contacts?

Yes, for the main contacts, the box terminal can connect to solid or stranded conductors with cross-sections ranging from a minimum of 2x 70 mm² to a maximum of 2x 240 mm².

What approvals does this box terminal have?

The box terminal has general product approvals and complies with EMC regulations. It also holds various certifications and declarations of conformity, which attest to its compliance with industry standards.

How can I ensure the box terminal is installed correctly?

Installation should be carried out in accordance with the manufacturer's guidelines and specifications. It's important to ensure that the terminal is securely attached and that the conductors are properly inserted and tightened.

What should I consider when selecting a box terminal for my application?

Consider the electrical requirements of your application, such as the voltage and current, as well as the size and type of conductors you will be using. Ensure that the box terminal is compatible with the contactors and overload relays in your system.

Are there any special features of this box terminal?

The Siemens 3RT1966-4G box terminal is designed for ease of use and reliability, with features that allow for the connection of a wide range of conductor sizes, including auxiliary contacts.

Can this terminal block be used in marine or offshore applications?

The box terminal has been tested and approved for use in various environmental conditions, including marine and offshore applications, as indicated by its certifications.

What is the significance of the design of the product?

The design of the product ensures that it can be used effectively in industrial control systems, providing a robust and reliable connection point for the conductors to the contactors and overload relays.