The Siemens SIRIUS 3RH21 is a 4-pole contactor relay for signal multiplication and interposing duties in control circuits. AC coil versions are offered for 24, 110 and 230 V AC with 4 NO, 3 NO + 1 NC and 2 NO + 2 NC contact arrangements, and can be expanded with front-mounted auxiliary switches.
Technical data
| Size | S00 |
|---|---|
| Mounting | Screw or snap-on mounting on TH35 DIN rail |
| Connection | Screw (box) or spring-loaded terminals, depending on article number |
| Standards | IEC 60947-1, IEC 60947-4-1, IEC 60947-5-1 |
| Contacts | 4 (basic unit) |
| Rated operational current Ie/AC-15 at 230 V | 10 A |
| Coil | AC, 24 / 110 / 230 V |
| Coil operating range | 50 Hz: 0.8–1.1 × Uc; 60 Hz: 0.85–1.1 × Uc |
| Force-guided contacts | Yes (IEC 60947-5-1 Annex L) |
| Expansion | Front-mounted auxiliary switches; S00 3RT2 accessories can be used |
Article numbers
| Contacts | Uc (V AC) | Screw terminals | Spring-loaded terminals |
|---|---|---|---|
| 4 NO | 24 | 3RH2140-1AB00 | 3RH2140-2AB00 |
| 4 NO | 110 | 3RH2140-1AF00 | 3RH2140-2AF00 |
| 4 NO | 230 | 3RH2140-1AP00 | 3RH2140-2AP00 |
| 3 NO + 1 NC | 24 | 3RH2131-1AB00 | 3RH2131-2AB00 |
| 3 NO + 1 NC | 110 | 3RH2131-1AF00 | 3RH2131-2AF00 |
| 3 NO + 1 NC | 230 | 3RH2131-1AP00 | 3RH2131-2AP00 |
| 2 NO + 2 NC | 24 | 3RH2122-1AB00 | 3RH2122-2AB00 |
| 2 NO + 2 NC | 110 | 3RH2122-1AF00 | 3RH2122-2AF00 |
| 2 NO + 2 NC | 230 | 3RH2122-1AP00 | 3RH2122-2AP00 |
Technical data and article numbers are based on Siemens catalog IC 10 · 2026 (chapter 5, SIRIUS 3RH2 contactor relays) and are for information only. Image is representative. Coil voltages not listed in the table are available on request according to the Siemens catalog.
For price, stock and lead time, use the Request a Quote button or call +90 533 945 27 94. Sending the article number from the table is enough.
Tags: 3RH21 AC, Siemens contactor relay, auxiliary contactor, SIRIUS 3RH2, 3RH2140-1AB00, 3RH2140-2AB00, 3RH2140-1AF00, 3RH2140-2AF00, 3RH2140-1AP00, 3RH2140-2AP00, 3RH2131-1AB00, 3RH2131-2AB00, 3RH2131-1AF00, 3RH2131-2AF00, 3RH2131-1AP00, 3RH2131-2AP00, 3RH2122-1AB00, 3RH2122-2AB00, 3RH2122-1AF00, 3RH2122-2AF00, 3RH2122-1AP00, 3RH2122-2AP00