top of page

Siemens SIRIUS 3RQ4 Coupling Relays

  • rebeccavanessendel
  • 1 hour ago
  • 2 min read
ree

Reliable, Compact, and Versatile Relays


Siemens SIRIUS 3RQ4 coupling relays in narrow design are used for coupling control signals from and to a controller, and they are available in different versions:


  • Coupling relay with integrated relay output

  • Coupling relay with plug-in relay

  • Coupling relay with integrated semiconductor output


Versions with protective coating on the printed circuit board according to IPC-A-610 are available for use in harsh ambient conditions (other device versions are available on request).


Benefits

  • All versions with screw terminals or spring-loaded terminals (push-in technology)

  • TOP wiring with spring-loaded terminals (push-in) for quick and reliable wiring

  • Low space requirements in the control cabinet thanks to a consistent width of 6.2 mm

  • Reduced stock-keeping due to fewer variance

  • Clearly visible functional state of the coupling relay by green LED

  • Integrated reverse polarity protection and EMC suppressor diode

  • Standardized accessories across the entire 3RQ4 series

  • Universal bridging option using connecting combs for all terminals

  • Galvanic isolation plate for isolating different voltages in neighboring devices

  • Device versions with protective coating on printed circuit board

  • Clip-on labels available as set for individual labeling

  • Highest quality (Made in Germany)

  • Sustainable product design (Siemens EcoTech label)


Coupling relay with integrated relay output

  • Relays fixed in enclosure for increased contact reliability

  • Device variants with hard gold-plated contacts, hence high contact reliability at low currents

  • ATEX certification

  • Safety Ready (B10d values available)


Coupling relay with plug-in relay

  • Fast replacement of the relays with existing wiring

  • Shorter installation times thanks to certified complete units

  • Individual relays available as spare parts

  • Device variants with hard gold-plated contacts, hence high contact reliability at low currents


Coupling relay with integrated semiconductor output

  • Long service life since there is no mechanical wear

  • High switching frequency thanks to short make-break times

  • Vibration-resistant

  • No contact bounce

  • Extremely high contact reliability

  • Noise-free switching

  • Low control power required

  • Switching of DC and capacitive loads


Application

  • Electrical separation between the input and output circuit

  • Adjustment of different signal levels

  • Signal amplification


ree

Application example motor controller

Suitable for use in harsh ambient conditions

Versions with protective coating on the printed circuit board according to IPC-A-610 are available for use in environments that are exposed to dust, condensation, rapid temperature changes and corrosion. These are intended for applications in rail systems, agriculture, mining, woodworking, etc.


Power-Flo Technologies is proud to partner with Siemens and their SIRIUS 3RQ4 coupling relays that provide a versatile, reliable, and space-saving solution for signal coupling across a wide range of industrial applications. With multiple versions tailored for different requirements—whether mechanical, plug-in, or semiconductor-based—these relays ensure dependable performance, easy installation, and long-term durability, even in harsh environments. Backed by Siemens’ commitment to quality and sustainability, the 3RQ4 series delivers flexibility, safety, and efficiency, making it the ideal choice for modern control systems.

 
 
bottom of page