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Siemens 3RH2122-1KF40-0LA4 — Contactors

Siemens 3RH2122-1KF40-0LA4 SIRIUS Auxiliary Contactor, 45 mm

MPN3RH2122-1KF40-0LA4
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Siemens SIRIUS 3RH2122-1KF40-0LA4, size S00 auxiliary contactor, 45 mm width, 117 mm depth, 110 V DC coil with integrated suppressor diode, screw and snap-on 35 mm DIN rail mounting, 2 instantaneous contacts.

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

3RH2122-1KF40-0LA4 — Identification
ParameterValue
Contactor frame sizeS00
3RH2122-1KF40-0LA4 — 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
3RH2122-1KF40-0LA4 — Control & Coil
ParameterValue
Control supply voltage typeDC
3RH2122-1KF40-0LA4 — Contacts & Poles
ParameterValue
Auxiliary contact reliability1 faulty switching per 100 million (17 V, 1 mA)
3RH2122-1KF40-0LA4 — 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
3RH2122-1KF40-0LA4 — Durability
ParameterValue
Durability (operating cycles, typ.)30 000 000
Durability with aux. switch block (cycles, typ.)10 000 000
3RH2122-1KF40-0LA4 — Environmental
ParameterValue
Operating temperature range-40 ... +70 °C
Storage temperature range-55 ... +80 °C
Installation altitude, max.2 000 m
3RH2122-1KF40-0LA4 — Mechanical
ParameterValue
Width45 mm
Height57.5 mm
Depth117 mm
3RH2122-1KF40-0LA4 — Specifications
ParameterValue
At AC10 000 1/h

Product details

Rated for 110 V DC coil operation with an integrated suppressor diode, this variant handles the DC control voltages common in PLC-driven panels and battery-backed safety circuits. The diode suppresses the inductive kick when the coil de-energizes — no external snubber needed on the van.

Switching ratings — what they mean on the line

The contact ratings are given per voltage, not as a single blanket current. At 24 V DC it switches 10 A; at 60 V DC it drops to 4.7 A; at 110 V DC it's 3 A; at 220 V DC it's 1.2 A. This voltage-dependent derating is typical for DC switching — arc extinction is harder at higher voltage, so the contactor's capability shrinks. On the AC side at 230 V it handles 10 A, at 400 V it's 3 A, and at 690 V it's 1 A. The 10 000 switching cycles per hour at AC and the 7–20 ms arcing time at DC give a realistic duty-cycle picture for conveyor or pump control. Two instantaneous contacts (NO/NC configurable via the auxiliary switch block) handle the signal-level interlocking. The design accepts an auxiliary switch extension, so you can add more contacts without replacing the whole unit — useful when a line-down fix needs extra feedback to the PLC.

RoHS compliance is documented with a substance prohibition date of 10/01/2009, covering the EU RoHS directive.

Mounting and clearances — panel integration notes

That 6 mm side gap is the one that catches people — if you're packing contactors side-by-side, leave at least that much breathing room for heat dissipation and wiring access. Terminal capacity accepts 2x 0.5–1.5 mm², 2x 0.75–2.5 mm², or 2x 4 mm² solid or stranded. That covers most control-circuit wiring gauges on the van; no need for special ferrules unless the panel spec demands them.

Frequently asked questions

What is 3RH2122-1KF40-0LA4's listed depth (117 mm) on this component line?

The depth is 117 mm, measured from the DIN rail mounting surface to the furthest point of the contactor body. Width is 45 mm, height is 57.5 mm.

Will 3RH2122-1KF40-0LA4 drop into a panel that was specified around 3RH2122-1BW40 without rewiring?

Both are SIRIUS S00 auxiliary contactors with the same footprint (45 mm wide, 117 mm deep, snap-on DIN rail), so mechanical fit is identical. However, the coil voltage and suppressor differ — 3RH2122-1KF40-0LA4 has a 110 V DC coil with a built-in suppressor diode, while the 1BW40 variant uses a different coil voltage. Check the coil rating matches your control circuit before swapping; the terminals and wiring slot are the same.

Where can I buy 3RH2122-1KF40-0LA4 and what is the lead time?

This part is sourced and quoted to order against an RFQ through independent distribution. Availability and current pricing are confirmed at quote time — no stock count or lead-time figure is published here because the channel picture changes daily. Submit an RFQ for a real-time commitment.

MPN
3RH2122-1KF40-0LA4