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Siemens 3RH1921-1CA10-ZW95 — Contactors

Siemens 3RH1921-1CA10-ZW95 SIRIUS Auxiliary Switch, S0 Snap-

MPN3RH1921-1CA10-ZW95

Siemens SIRIUS 3RH1921-1CA10-ZW95 auxiliary switch, 1 NO, for S0 contactor relay and power contactor, snap-on front mounting, mirror contact per IEC 60947-4-1, IP20 front, AC-15 6 A at 230 V.

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

3RH1921-1CA10-ZW95 — Identification
ParameterValue
Contactor frame sizeS0
3RH1921-1CA10-ZW95 — Ratings & Performance
ParameterValue
Rated value @ 24 V10 A
Rated value @ 60 V4.7 A
Rated value @ 110 V3 A
Rated value @ 220 V1.2 A
3RH1921-1CA10-ZW95 — Contacts & Poles
ParameterValue
Auxiliary contact reliability1 faulty switching per 100 million (17 V, 1 mA)
3RH1921-1CA10-ZW95 — Connection & Mounting
ParameterValue
Conductor cross-section, solid or stranded2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)
Conductor cross-section, finely stranded w/ ferrule2x (0.5 ... 1.5 mm²), 2x (0.75 ... 2.5 mm²)
Mounting methodsnap-on mounting
3RH1921-1CA10-ZW95 — Environmental
ParameterValue
Operating temperature range-25 ... +60 °C
Storage temperature range-55 ... +80 °C
3RH1921-1CA10-ZW95 — Mechanical
ParameterValue
Width10 mm
Height38 mm
Depth51 mm

Product details

S0 auxiliary switch for contactor front-mount

It carries one normally open instantaneous contact and is rated as a mirror contact per IEC 60947-4-1 when used with 3RT1 contactors — meaning the NO position mechanically mirrors the main contact state, critical for safety circuits that need positive feedback of contactor weld or dropout. The switch block measures 10 mm wide, 51 mm deep, and 38 mm high, fitting the standard S0 footprint without consuming extra DIN rail space. Snap it onto the contactor front, wire the terminals — 2x (0.5…1.5 mm²) solid or 2x (0.75…2.5 mm²) stranded, or 2x (20…16) AWG / 2x (18…14) AWG — and it's live. IP20 on the front face keeps fingers out but expects enclosure protection beyond that.

The auxiliary contact is rated for AC-15 (solenoid/contactor coil) and DC-13 (electromagnet) loads at multiple voltages. At 230 V AC, it switches 6 A; at 400 V AC, 3 A; at 690 V AC, 1 A. For DC circuits, it handles 10 A at 24 V, 4.7 A at 60 V, 1.2 A at 220 V, and 0.26 A at 600 V. These are the operational currents — match them to your coil inrush or holding load, not the main contactor's motor current.

Substance prohibitance date is July 1, 2006, indicating RoHS compliance from that point. It is designed as a mirror contact per IEC 60947-4-1, which implies the manufacturer has submitted it to the relevant type tests under that standard.

Frequently asked questions

Where can I buy 3RH1921-1CA10-ZW95 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.

What is the closest functional second-source for 3RH1921-1CA10-ZW95?

The 3RH2122-1BA40 is a different block — 2 NO contacts instead of 1 NO, and a different form factor. It will not drop into a panel wired for the 3RH1921-1CA10-ZW95 without rewiring the extra contact and checking the S0 mounting compatibility. Stick with the exact order code for a drop-in replacement.

What compliance documentation does Siemens provide for 3RH1921-1CA10-ZW95?

The part is RoHS compliant (substance prohibitance date July 1, 2006) and designed as a mirror contact per IEC 60947-4-1. Standard Siemens SIRIUS declaration of conformity and RoHS certificates are available on request.

MPN
3RH1921-1CA10-ZW95