Contactor relay Siemens SIRIUS 3RH2122-1BB40
Contactor relays, size S00, with accessories
IEC/EN 60947‑1, IEC/EN 60947‑4‑1, IEC/EN 60947‑5‑1
The 3RH2 contactor relays are available with screw or spring-loaded terminals. The basic unit contains four contacts with terminal designations according to EN 50011.
The 3RH2 contactor relays are suitable for use in any climate. They are finger-safe according to IEC 60529.
The 3RH21 coupling contactor relays for switching auxiliary circuits are tailored to the special requirements of working with electronic controls.
High contact stability at low voltages and currents, suitable for solid-state circuits with currents ≥ 1 mA at a voltage of ≥ 17 V.
RC elements, varistors, diodes or diode assemblies (combination of a diode and a Zener diode) can be plugged onto all 3RH2 contactor relays from the front for damping opening surges in the coil. The plug-in direction is determined by a coding device.
Coupling contactor relays have a low power consumption and an extended solenoid coil operating range.
Depending on the version, the solenoid coils of the coupling contactor relays are supplied either without overvoltage damping (versions 3RH21..‑.HB40 or 3RH21..‑.MB40‑0KT0) or with a diode or suppressor diode connected as standard.
The accessories for the 3RT2 contactors in size S00 can also be used for the 3RH2 contactor relays, see .
The 3RH21 contactor relays (with the exception of coupling contactor relays) can be expanded by up to four contacts by the addition of mounted auxiliary switches.
The auxiliary switch can easily be snapped onto the front of the contactor relays. The auxiliary switch has a centrally positioned release lever for disassembly.
The conventional front auxiliary contacts fulfill the characteristics of positively driven operation and are therefore suitable for safety applications.
Contactor relays in safety-related applications
Contactor relays are a significant part of safety-related applications. They are generally the actuators that perform the switching operation leading to the safe disconnection of the corresponding application or system.
Contactor relays with positively driven operation according to IEC 60947‑5‑1 are generally required for use in safety-related applications. Most of our contactors meet this requirement; a corresponding note can be found in the technical product data sheet.
Contactor relays with increased tamper protection
Increased tamper protection is ensured either by using our contactor relay versions with permanently mounted auxiliary switches installed in the factory (e.g. 3RH22 contactor relays), or by using the as an accessory.
Article No. scheme
The Article No. scheme shows an overview of product versions for better understanding of the logic behind the article numbers.
For your order, please use the article numbers specified in the selection and ordering data.
Contactor relay, 2 NO + 2 NC, 24 V DC, Size S00, screw terminal