Product Description

Siemens 3RH2911-2HA22 Auxiliary Contact Block – 2 NO + 2 NC

The Siemens 3RH2911-2HA22 is a front-mountable auxiliary contact block from the Siemens SIRIUS range, designed for compatible 3RT2 contactors and 3RH2 contactor relays. It provides 2 normally open (NO) and 2 normally closed (NC) instantaneous auxiliary contacts with spring-loaded terminal connections. Siemens currently lists this article as an active product.

The auxiliary contact block is designed to expand the control, interlocking and signalling capabilities of a compatible contactor without changing its main power-switching function.

Siemens SIRIUS Auxiliary Contact Block

The 3RH2911-2HA22 is used to provide additional auxiliary contacts for industrial control circuits.

These contacts can be used independently of the main power circuit for applications such as:

• Contactor status feedback

• PLC input signals

• Electrical interlocking

• Control-circuit logic

• Machine sequencing

• Auxiliary signalling

• Motor-control circuits

• Industrial automation

Siemens specifies this auxiliary switch for 3RT2 contactors and 3RH2 contactor relays, including compatible 3RT2.1, 3RT2.2, 3RT2.3 and 3RT2.4 devices.

2 NO + 2 NC Auxiliary Contacts

The 3RH2911-2HA22 provides a total of 4 instantaneous auxiliary contacts:

2 NO + 2 NC

The contact arrangement is identified with the corresponding .1/.2 and .3/.4 current paths. Siemens specifies 2 instantaneous NC contacts and 2 instantaneous NO contacts for this product.

This combination provides flexibility for both control and monitoring circuits.

Typical applications include:

• Contactor ON/OFF feedback

• PLC monitoring

• Electrical interlocking

• Auxiliary relay logic

• Machine sequencing

• Status indication

• Alarm signalling

• Control-system feedback

Front-Mounting Design

The 3RH2911-2HA22 is designed to snap onto the front of compatible contactors and contactor relays.

This front-mounting arrangement allows additional auxiliary contacts to be added while maintaining a compact control-panel configuration. Siemens identifies the device as a front-mounted auxiliary switch for the compatible SIRIUS contactor and contactor-relay range.

It is particularly useful for:

• Motor starters

• Machine-control panels

• Compact automation cabinets

• OEM control systems

• Industrial electrical assemblies

Spring-Loaded Terminals

The product uses spring-loaded terminal connections, providing a practical wiring solution for industrial control circuits. Siemens' current product description specifically identifies the terminal type as spring-loaded terminal.

This connection arrangement can simplify wiring and support consistent control-panel assembly.

Compatibility with 3RT2 and 3RH2

The 3RH2911-2HA22 is intended for compatible Siemens SIRIUS devices, including:

• 3RT2.1 contactors

• 3RT2.2 contactors

• 3RT2.3 contactors

• 3RT2.4 contactors

• 3RH2 contactor relays

Compatibility should be checked against the exact contactor or contactor-relay article number before installation.

Instantaneous Auxiliary Contacts

All four auxiliary contacts in this configuration are instantaneous. Siemens specifies 2 instantaneous NC and 2 instantaneous NO contacts, with no delayed contacts in this arrangement.

This makes the device suitable for immediate contactor-state feedback and control logic.

Industrial Automation Applications

The 3RH2911-2HA22 can expand the control functionality of compatible contactors and contactor relays.

Motor Control

The auxiliary contacts can provide contactor-state feedback, interlocking and control signals in motor starters.

PLC Systems

The contacts can be connected to PLC digital inputs for monitoring the operating state of a contactor.

Machine Control

The NO and NC contacts can support machine sequencing, control logic and interlocking.

Industrial Control Panels

The front-mounted design allows auxiliary functionality to be added without requiring a separate remote relay in many applications.

Automation Systems

The auxiliary contacts can provide additional control and signalling paths within automated machinery.

Suitable for OEMs and Panel Builders

The 3RH2911-2HA22 is suitable for OEM machine manufacturers, electrical panel builders, automation integrators and industrial maintenance professionals.

Its 2 NO + 2 NC contact configuration, front-mounting design and spring-loaded terminals make it a practical accessory for expanding compatible Siemens SIRIUS contactor and contactor-relay assemblies.

Key Features

• Siemens SIRIUS auxiliary contact block

• Article number 3RH2911-2HA22

• Front-mountable design

• 2 NO + 2 NC auxiliary contacts

• All contacts instantaneous

• Spring-loaded terminals

• Compatible with selected 3RT2 contactors

• Compatible with 3RH2 contactor relays

• Suitable for PLC feedback

• Suitable for electrical interlocking

• Suitable for machine-control applications

• Suitable for industrial automation

• Suitable for OEM and panel-building applications

Benefits

• 2 NO + 2 NC contacts: Provides four additional auxiliary switching paths.

• Front mounting: Allows easy integration directly onto compatible SIRIUS devices.

• Spring-loaded terminals: Provides a practical connection method for control wiring.

• PLC integration: Supports contactor-state feedback.

• Interlocking support: NC contacts can be used in suitable interlocking circuits.

• Flexible control logic: NO and NC contacts provide multiple signalling possibilities.

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

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

Why Choose Siemens 3RH2911-2HA22?

The Siemens 3RH2911-2HA22 is a practical solution for applications requiring additional contactor control, interlocking and signalling contacts.

Its 2 NO + 2 NC instantaneous contact arrangement, front-mounting configuration and spring-loaded terminals make it suitable for industrial motor-control panels, automation systems and OEM machinery.

The product is currently listed by Siemens as an active product, providing a current accessory option for compatible 3RT2 contactors and 3RH2 contactor relays.

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 3RH2911-2HA22?

It is a front-mountable auxiliary contact block for compatible Siemens 3RT2 contactors and 3RH2 contactor relays.

2. How many auxiliary contacts does it provide?

It provides 2 normally open and 2 normally closed contacts.

3. Are the contacts instantaneous?

Yes. Siemens specifies 2 instantaneous NO and 2 instantaneous NC contacts.

4. Where is the auxiliary block mounted?

It is designed to snap onto the front of compatible Siemens contactors and contactor relays.

5. What type of terminals does it use?

It uses spring-loaded terminals.

6. Which devices are compatible?

Siemens specifies compatibility with 3RT2.1, 3RT2.2, 3RT2.3, 3RT2.4 and 3RH2 devices.

7. What can the auxiliary contacts be used for?

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

8. Does it switch the main electrical load?

No. It provides auxiliary contacts for control and signalling; the main load remains switched by the compatible contactor.

9. Is it suitable for OEM machinery?

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

10. Where can I buy Siemens 3RH2911-2HA22 in India?

You can explore the Siemens product range at SB Smart for Siemens auxiliary contact blocks, contactors, relays and other industrial automation products.