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Siemens 3RH1122-1BG40 — Contactors

Siemens 3RH1122-1BG40 SIRIUS Auxiliary Contactor, 125V, 2 NO

MPN3RH1122-1BG40

Siemens SIRIUS, auxiliary contactor, size S00, 3RH1122-1BG40, 125 V rated, 2 NO instantaneous contacts, 10 A at 24 V, IP20, screw and snap-on mounting.

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

3RH1122-1BG40 — Identification
ParameterValue
Contactor frame sizeS00
3RH1122-1BG40 — 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 V6 A
Rated value @ 24 V10 A
Rated value @ 110 V1 A
Rated value @ 220 V0.27 A
3RH1122-1BG40 — Control & Coil
ParameterValue
Control supply voltage typeDC
3RH1122-1BG40 — Contacts & Poles
ParameterValue
Auxiliary contact reliability1 faulty switching per 100 million (17 V, 1 mA)
3RH1122-1BG40 — Connection & Mounting
ParameterValue
Conductor cross-section, solid2x (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
3RH1122-1BG40 — Durability
ParameterValue
Durability (operating cycles, typ.)30 000 000
Durability with aux. switch block (cycles, typ.)10 000 000
3RH1122-1BG40 — Environmental
ParameterValue
Operating temperature range-25 ... +60 °C
Storage temperature range-55 ... +80 °C
Installation altitude, max.2 000 m
3RH1122-1BG40 — Mechanical
ParameterValue
Width45 mm
Height57.5 mm
Depth72 mm

Product details

Rated 125 V with two normally-open instantaneous contacts, it carries 10 A at 24 V and derates to 1 A at 690 V.

The 2 NO instantaneous contacts switch without delay — no leading or lagging action, no make-before-break overlap. That means the contacts close and open at the same instant the coil energizes or drops, which matters when you're using them for a safety feedback loop or a fast interlock where timing skew between contacts could cause a race condition. Mechanical life is 30 million cycles typical, so in a machine that cycles once per minute you get about 57 years of mechanical life before the springs fatigue.

Wire termination and environment

Terminals accept solid conductors: 2x 0.5–1.5 mm², 2x 0.75–2.5 mm², or 2x 4 mm² — that covers the common control-wire sizes from 20 AWG through 12 AWG.

Frequently asked questions

Where can I buy the 3RH1122-1BG40 and how is it quoted?

Sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time — no stock count or price is published here.

What is the closest functional second-source to the 3RH1122-1BG40?

The 3RH2122-1BW40 is a peer in the same SIRIUS size S00 family with 2 NO contacts, but it carries a different coil voltage rating — verify the 3RH2122-1BW40 coil matches your control voltage before substituting. The 3RH1122-1BG40 uses a 125 V rated coil; the 3RH2122-1BW40 uses a different coil voltage. Mechanical footprint and terminal layout are identical, so it drops into the same DIN-rail slot without rewiring the main power circuit, but the coil supply must be confirmed.

What is the depth of the 3RH1122-1BG40?

The depth is 72 mm. Combined with the 45 mm width and 57.5 mm height, it occupies about 0.16 liters of panel volume — tight enough for high-density DIN-rail layouts.

What wire sizes does the 3RH1122-1BG40 accept?

Solid conductors: 2x 0.5–1.5 mm², 2x 0.75–2.5 mm², or 2x 4 mm². That covers 20 AWG through 12 AWG control wiring. Ferruled stranded wires within the same cross-section ranges also fit.

Will the 3RH1122-1BG40 drop into a panel specified around the 3RH2122-1BW40 without rewiring?

Yes, the mechanical footprint is identical — both are size S00 with the same 45 mm width, screw and snap-on mounting, and the same terminal layout. The main power and signal wires land in the same positions. The only difference is the coil voltage: the 3RH1122-1BG40 is rated 125 V; the 3RH2122-1BW40 uses a different coil voltage. If your control voltage is 125 V, the swap is wire-for-wire. If not, you need to change the coil supply.

What compliance documentation does Siemens provide for the 3RH1122-1BG40?

The part carries RoHS compliance with a substance prohibition date of July 1, 2006. It is designed to meet IEC 60947-5-1 for control circuit devices and switching elements. The reference code per IEC 81346-2 is K. Surge voltage resistance is rated at 6 kV. Standard Siemens SIRIUS documentation includes a CE declaration of conformity and the product datasheet.

MPN
3RH1122-1BG40