Shopping.co.uk

Siemens Auxiliary Relay - 3RH2

Siemens Auxiliary Relay - 3RH2

Safely turn an electric motor on and off using this contactor relay from Siemens. It has a high co...

Best current price£30.00from eBay

Best offers

Shopping.co.uk recommended and popular offers

All Offers

14 offers from £30.00 - £299.51

View price history by clicking the chart icon.

eBaySiemens 3RH2131-1BB40
£15.60 delivery
£30.00
Visit shop
Tameson UKSiemens Click And Go Auxiliary Relay - 3Rh21221bb40
Free delivery in 1–3 days
£38.73
Visit shop
Rapid Online - Rapid Electronics Ltd.Siemens 3RH2122-1BB40 SIRIUS Contactor 24V DC 10A 2NO+2NC S00 size
Free delivery in 1–3 days
£39.25
Visit shop

Used Offers

4 offers from £18.94 - £151.00

View price history by clicking the chart icon.

eBaySiemens Auxiliary Relay 3RH2122-1BB40 Contactor Relay 24V DC Relay 2NO + 2NC
£30.13 delivery
£18.94
Visit shop

Product Information

Full details

This Siemens 3RH2122-1BB40 contactor relay is designed for industrial automation professionals who need a reliable component for switching and controlling electric motors and loads. Its key benefit is robust electrical safety and signaling capabilities, even in demanding environments. A potential caveat is its specific 24V DC control supply voltage, requiring compatible power sources. This compact and durable relay offers a high contact voltage rating of 690V AC, can handle up to 10A, and supports two auxiliary switches for expanded functionality.

All features

Series3RH2
Model Part Number3RH2122-1BB40
BrandSiemens

Extended Product Information

FAQs

What is the rated control supply voltage for this Siemens contactor?

The rated control supply voltage is 24V DC.

How many auxiliary contacts does this relay have?

It includes 2 normally closed (NC) and 2 normally open (NO) auxiliary contacts.

Can I add more auxiliary switches to this contactor?

Yes, you can attach two additional auxiliary switches for expanded signaling capabilities.

What is the maximum AC voltage this contactor can switch?

It has a high contact voltage rating of up to 690V AC.

What is the maximum current rating for the main contacts?

The main contacts are rated to handle up to 10 Amps.

What is the operating temperature range?

It is designed to operate within a broad temperature range of -25°C to +60°C.

Does this unit have protection against short circuits?

Yes, it features an integrated fuse link for enhanced electrical safety during short circuit events.

How are the auxiliary circuits connected?

The auxiliary circuit connection type is a screw connection.

Troubleshooting

Contactor does not energize when control voltage is applied.

Verify the control supply voltage is exactly 24V DC and correctly connected to A1/A2. Check for any open circuits or loose connections in the control wiring. Ensure the auxiliary switches (if installed) are not preventing activation.

Contactor energizes but does not make contact.

Check the main power terminals for secure connections. Inspect the main power circuit for faults. Ensure the load does not exceed the 10A rating.

Contactor hums loudly or chatters.

This could indicate an under-voltage or fluctuating control supply. Ensure a stable 24V DC supply. Check for foreign objects interfering with the coil or armature.

Auxiliary contacts are not switching as expected.

Confirm that auxiliary switches are correctly installed and wired. Verify the mounting orientation and ensure they are properly seated. Check the specific NC/NO configuration of the attached switches.

Device overheats during operation.

Ensure the load current does not exceed the 10A rating. Check for adequate ventilation around the contactor. Verify connections are tight, as loose connections can cause resistance heating.

Pros and Cons

Pros

  • High durability and reliability from Siemens.
  • Suitable for heavy-duty applications with a 690V AC rating.
  • Offers expandable control with auxiliary switch mounting.
  • Enhanced safety features like integrated fuse protection.
  • Operates across a wide temperature range, ideal for industrial settings.

Cons

  • Requires a specific 24V DC control supply voltage, limiting compatibility with other voltages.
  • Auxiliary switches are not pre-installed and must be purchased and attached separately.
  • Primarily designed for industrial environments, may be over-specified for simpler applications.
  • Connection type is screw terminal, which may require specific tools or training for installation.
  • Relatively high contact voltage rating might not be necessary for all low-power applications.

Setup, Compatibility & Care

Setup:

  1. Ensure the power supply matches the 24V DC control supply voltage requirement.
  2. Mount the contactor relay securely onto a DIN rail or panel.
  3. Connect the main power terminals according to your circuit diagram and load requirements (up to 10A, 690V AC).
  4. Connect the control circuit to the coil terminals (A1/A2) with the correct polarity for 24V DC.
  5. If needed, attach auxiliary switches to the designated front or side mounting points. Connect their terminals via screw connection as per the switch’s and control system's specifications.

Compatibility:

  • Designed for use with 24V DC control circuits.
  • Compatible with industrial control systems requiring motor switching up to 10A and 690V AC.
  • Can be integrated with standard industrial automation components.

Care:

  • Keep the contactor clean and free from dust and debris, especially around the contacts and coil.
  • Periodically inspect connections for tightness and signs of corrosion.
  • Avoid exposing the unit to excessive moisture or corrosive atmospheres unless appropriately protected.
  • Ensure ventilation around the unit is not obstructed.

Price History

DatePrice
Visit shop