Siemens 3RH21311AN20 Contactor Relay
3RH21311AN20 Specifications
| Parameter | Value |
|---|---|
| Base Product Number | 3RH21311 |
| Coil Voltage | 220VAC |
| Coil Power | 37VA |
| Contact Form | 3PST-NO (3 Form A) |
| Contact Rating | See alternate records |
| Mounting Type | Chassis Mount, DIN Rail |
| Must Operate Voltage | 187 VAC |
| Operate Time | 33 ms |
| Operating Temperature | 25°C ~ 60°C |
| Features | Auxiliary Contacts |
| Package | Bulk |
The 3RH21311 series contactor relays mount via chassis or DIN rail and share a common 33 ms operate time across voltage variants. The seed unit specifies a 3PST-NO contact form, while some alternates list 4PST-3NO/1NC (3 Form A, 1 Form B).
Selection Trade-offs
-
Coil voltage mismatch: The 220VAC seed rating requires 187 VAC minimum operate voltage; installing this unit on a 208V or 240V system without verifying must-operate margin risks intermittent dropout.
-
Contact configuration ambiguity: The seed lists "3PST-NO" only, while alternate records for the same base PN show a 4PST-3NO/1NC option—confirm the auxiliary NC contact presence before specifying for safety-circuit applications.
-
Package type constraints: The seed ships in bulk packaging; alternate variants are available in box quantities, which may affect kitting and panel assembly workflows.
-
Operating temperature ceiling: The 60°C upper limit restricts use in enclosed panels with significant heat load; thermal imaging or panel derating studies may be required.
Family Voltage Comparison
| MPN | Coil Voltage | Must Operate | Contact Form | Package |
|---|---|---|---|---|
| 3RH21311AN20 | 220VAC | 187 VAC | 3PST-NO | Bulk |
| 3RH21311AN60 | 200~220VAC | — | 4PST-3NO/1NC | Box |
| 3RH21311AM20 | 208VAC | 176.8 VAC | 4PST-3NO/1NC | Box |
| 3RH21311AK20 | 120VAC | 102 VAC | 4PST-3NO/1NC | Box |
| 3RH21311AP60 | 240VAC | 204 VAC | 3PST-NO | Bulk |
| 3RH21311AP00 | 230VAC | 195.5 VAC | 3PST-NO | Bulk |
| 3RH21311AK60 | 110VAC | 93.5 VAC | 3PST-NO | Bulk |
| 3RH21311AD00 | 42VAC | 35.7 VAC | 4PST-3NO/1NC | Box |
| 3RH21311AV00 | 400VAC | 340 VAC | 4PST-3NO/1NC | Box |
All listed MPNs belong to the Siemens 3RH21311 series; the reader must qualify each variant independently for a given application. Contact form and auxiliary NC presence differ among records sharing the same base PN.
Why these are similar: All variants share identical mounting (chassis/DIN), 37VA coil power, 33 ms operate time, and operate within the 25°C–60°C range. They differ primarily in coil voltage and, for some records, the presence of an auxiliary NC contact.