Product Description

Siemens 3RH2911-1HA01 Auxiliary Contact Block – 1 NC

The Siemens 3RH2911-1HA01 is a front-mountable auxiliary contact block from the Siemens SIRIUS 3RH29 accessory range. It provides 1 normally closed (NC) instantaneous auxiliary contact and is designed for compatible 3RT2 contactors and 3RH2 contactor relays. The unit uses screw-terminal connections and is designed for snapping onto the front of compatible devices.

The accessory adds an additional auxiliary switching path for contactor control, interlocking, feedback and signalling applications without changing the main power-switching function of the connected contactor.

Siemens SIRIUS Auxiliary Contact Block

The 3RH2911-1HA01 is used to expand the auxiliary functionality of compatible Siemens SIRIUS contactors and contactor relays.

The additional NC contact can be incorporated into control circuits for:

• Contactor status feedback

• Electrical interlocking

• PLC input signals

• Control-circuit logic

• Machine sequencing

• Auxiliary signalling

• Motor-control circuits

• Industrial automation

Siemens specifies this article for compatible 3RT2.1, 3RT2.2, 3RT2.3, 3RT2.4 and 3RH2 devices.

1 NC Instantaneous Auxiliary Contact

The 3RH2911-1HA01 provides 1 normally closed (NC) instantaneous contact.

The contact path is identified as .1/.2, making it suitable for control and monitoring circuits where an NC auxiliary signal is required.

Typical applications include:

• Contactor interlocking

• Status monitoring

• PLC feedback

• Auxiliary signalling

• Machine-control logic

• Relay circuits

• Control-system feedback

The auxiliary contact should be operated within its applicable electrical ratings.

Front-Snap Mounting

The 3RH2911-1HA01 is designed for snapping onto the front of compatible SIRIUS devices.

This arrangement allows the auxiliary contact to be added directly to the front of the contactor or contactor relay, helping maintain a compact and organized control-panel layout. Siemens lists the accessory for S00 to S3 contactor and contactor-relay sizes.

It is suitable for applications such as:

• Motor starters

• Machine-control panels

• Automation cabinets

• OEM control systems

• Industrial electrical assemblies

Screw-Terminal Connection

The 3RH2911-1HA01 uses screw-type terminals for the auxiliary circuit. Siemens specifies compatible conductor cross-sections from 0.5 to 2.5 mm² for the auxiliary contact connection.

This provides a familiar wiring method for electrical panel builders and maintenance teams.

Instantaneous Contact Operation

The contact is instantaneous, meaning it follows the operating state of the associated contactor or contactor relay without an intentional time delay. Siemens specifies 1 instantaneous NC contact and no NO or changeover contacts for this article.

This makes the accessory suitable for immediate interlocking, feedback and signalling functions.

Mirror Contact Capability

When used with a compatible 3RT2 contactor, Siemens specifies the auxiliary contact as capable of serving as a mirror contact according to IEC 60947-4-1. The product also has positively driven operation according to IEC 60947-5-1.

This can be useful in appropriate monitoring and safety-related control architectures. The complete safety function must always be designed and validated for the specific machine or installation.

Industrial Automation Applications

The 3RH2911-1HA01 can provide an additional NC control path in a wide range of industrial applications.

Motor Control

The NC contact can be incorporated into motor-starter interlocking and contactor-status circuits.

PLC Systems

It can provide a contactor-related signal to a compatible PLC digital input.

Machine Control

The auxiliary contact can support sequencing, interlocking and control logic.

Industrial Control Panels

The front-mounted design allows auxiliary functionality to be added directly to a compatible contactor.

Automation Systems

The NC contact can provide an additional feedback or signalling path within automated machinery.

Suitable for OEMs and Panel Builders

The 3RH2911-1HA01 is suitable for OEM machine manufacturers, electrical panel builders, automation integrators and industrial maintenance professionals.

Its 1 NC instantaneous contact, front-snap mounting and screw-terminal connection make it a practical accessory for expanding compatible Siemens SIRIUS contactor and contactor-relay assemblies.

Key Features

• Siemens SIRIUS 3RH29 auxiliary contact block

• Article number 3RH2911-1HA01

• Front-snap mounting

• 1 NC auxiliary contact

• Instantaneous contact operation

• Contact path .1/.2

• Screw terminals

• Compatible with selected 3RT2 contactors

• Compatible with 3RH2 contactor relays

• Suitable for PLC feedback

• Suitable for electrical interlocking

• Suitable for signalling and control

• Suitable for industrial automation

Benefits

• 1 NC contact: Provides an additional normally closed switching path.

• Front mounting: Allows direct installation onto compatible SIRIUS devices.

• Instantaneous operation: Auxiliary contact responds directly to the associated device state.

• Screw terminals: Provides a familiar industrial wiring method.

• Interlocking support: The NC contact is useful in suitable interlocking circuits.

• PLC integration: Can provide auxiliary status information.

• Compact design: Helps maintain an organized control-panel layout.

• Easy expansion: Adds auxiliary functionality without replacing the main contactor.

Why Choose Siemens 3RH2911-1HA01?

The Siemens 3RH2911-1HA01 provides a simple way to add one instantaneous normally closed auxiliary contact to compatible Siemens SIRIUS contactors and contactor relays.

Its front-snap mounting, .1/.2 NC contact path and screw-terminal connection make it suitable for additional feedback, signalling, interlocking and machine-control functions. Siemens currently lists the article as an active product.

For OEMs, panel builders and automation integrators, it provides a compact solution for expanding auxiliary control functionality within an existing SIRIUS assembly.

Delivery Across India

SB Smart supplies Siemens industrial electrical and automation products across Faridabad, Gurgaon/Gurugram, Delhi NCR, Haryana, Noida, Punjab, Mumbai and all major cities across India.

Major delivery locations include:

• Faridabad

• Gurgaon/Gurugram

• Delhi

• Delhi NCR

• Noida

• Greater Noida

• Haryana

• Punjab

• Mumbai

• Pune

• Ahmedabad

• Bengaluru

• Hyderabad

• Chennai

• Kolkata

• Jaipur

• Chandigarh

• Lucknow

• Indore

• Surat

• Vadodara

• Nagpur

• Coimbatore

• And other major cities across India

Frequently Asked Questions

1. What is Siemens 3RH2911-1HA01?

It is a Siemens SIRIUS front-mountable auxiliary contact block with 1 normally closed instantaneous contact.

2. How many auxiliary contacts does it provide?

It provides 1 NC auxiliary contact.

3. What is the contact path?

The NC contact path is .1/.2.

4. Is the contact instantaneous?

Yes. It is an instantaneous NC auxiliary contact.

5. How is it mounted?

It is designed for snap-on front mounting on compatible Siemens SIRIUS devices.

6. What type of terminals does it use?

It uses screw-type terminals.

7. Which Siemens devices are compatible?

It is specified for compatible 3RT2.1, 3RT2.2, 3RT2.3, 3RT2.4 and 3RH2 devices.

8. What can the NC contact be used for?

It can be used for PLC feedback, signalling, electrical interlocking, control logic and machine sequencing.

9. Does it switch the main electrical load?

No. It provides an auxiliary control contact; the main load remains switched by the compatible contactor.

10. Is it suitable for OEM machinery?

Yes. It is suitable for OEM machine builders, panel manufacturers, automation integrators and industrial maintenance applications.