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Siemens 3RH2122-1FB40 — Contactors

Siemens 3RH2122-1FB40 SIRIUS Auxiliary Contactor, 24 VDC, 2

MPN3RH2122-1FB40
Active

Siemens SIRIUS auxiliary contactor, size S00, 24 VDC coil, 2 NO instantaneous contacts, screw and snap-on mounting onto 35 mm DIN rail, 45 mm width, 73 mm depth.

$25.40 – $72.87Ref. price · indicative, final on quote
Source DocumentedChannel stated on listing & quote
Condition PhotosReal unit photos / video on request
WhatsApp AnswersFast human replies for machine-down parts
Worldwide DispatchDHL/FedEx — transit quoted per order
Independent China distributor & sourcing agent· Listing updated Sep 2026

Specifications

3RH2122-1FB40 — Identification
ParameterValue
Contactor frame sizeS00
3RH2122-1FB40 — Ratings & Performance
ParameterValue
Rated operational current, AC-12, max.10 A
Rated value @ 400 V3 A
Rated value @ 500 V2 A
Rated value @ 690 V1 A
Rated value @ 230 V10 A
Rated value @ 24 V10 A
Rated value @ 60 V4.7 A
Rated value @ 110 V3 A
Rated value @ 220 V1.2 A
3RH2122-1FB40 — Control & Coil
ParameterValue
Control supply voltage typeDC
3RH2122-1FB40 — Contacts & Poles
ParameterValue
Auxiliary contact reliability1 faulty switching per 100 million (17 V, 1 mA)
3RH2122-1FB40 — Connection & Mounting
ParameterValue
Conductor cross-section, solid or stranded2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²), 2x 4 mm²
Conductor cross-section, finely stranded w/ ferrule2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)
Mounting methodscrew and snap-on mounting onto 35 mm DIN rail
3RH2122-1FB40 — Durability
ParameterValue
Durability (operating cycles, typ.)30 000 000
Durability with aux. switch block (cycles, typ.)10 000 000
3RH2122-1FB40 — Environmental
ParameterValue
Operating temperature range-25 ... +60 °C
Storage temperature range-55 ... +80 °C
Installation altitude, max.2 000 m
3RH2122-1FB40 — Mechanical
ParameterValue
Width45 mm
Height57.5 mm
Depth73 mm
3RH2122-1FB40 — Specifications
ParameterValue
At AC10 000 1/h

Product details

It carries 2 NO instantaneous contacts rated for 10 A at 24 V and 230 V, with a 24 VDC coil that draws 4 W closing power. The built-in diode surge suppressor handles the inductive kick from the DC coil, so you don't need an external flyback diode across the coil terminals.

The 2 NO contacts are rated for AC-15 and DC-13 control-circuit duty. At 24 V they switch 10 A; at 230 V the same 10 A holds. For higher voltages the current derates: 4.7 A at 60 V, 3 A at 110 V, 1.2 A at 220 V, 3 A at 400 V, 0.5 A at 440 V, 2 A at 500 V, 0.26 A at 600 V, and 1 A at 690 V.

RoHS compliance date is 2009-10-01 per the substance prohibition date. The product extension auxiliary switch is available as an add-on, and the design uses a diode surge suppressor across the coil.

Frequently asked questions

Who supplies 3RH2122-1FB40 and how is it quoted for volume purchases?

This part is supplied through independent distribution channels. Volume pricing and availability are confirmed at quote time against an RFQ — no stock count or price is listed here.

Will 3RH2122-1FB40 drop into a panel that was specified around 3RH2122-1BA40 without rewiring?

Yes — both are SIRIUS S00 auxiliary contactors with the same 45 mm width, 73 mm depth, and DIN-rail mounting. The 1FB40 uses a 24 VDC coil with a diode suppressor; the 1BA40 uses a different coil voltage. If the control voltage matches, the swap is mechanical and electrical drop-in.

What compliance documentation does this brand provide for 3RH2122-1FB40?

The part carries RoHS compliance per the substance prohibition date of 2009-10-01. It is designed for pollution degree 3 and operates within -25 to +60 °C. Full IEC and UL documentation is available from the manufacturer.

MPN
3RH2122-1FB40