Siemens 3RT20161AN21 S00 Contactor
Installation Context
The 3RT20161AN21 is an electromechanical contactor in the Siemens S00 size series, designed for DIN-rail or chassis mounting inside motor-control and power-distribution enclosures. The 9 A contact rating and 220 VAC coil voltage place it in the lower end of the standard IEC AC-3 duty range commonly found in compact starter assemblies and auxiliary control circuits.
Technical Parameters
| Parameter | Value |
|---|---|
| Base Product Number | 3RT2016 |
| Contact Rating | 9 A |
| Contact Form | 3PST-NO (3 Form A) |
| Coil Voltage | 220 VAC |
| Coil Power | 24.3 VA |
| Must Operate Voltage | 187 VAC |
| Operate Time | 35 ms |
| Mounting | Chassis Mount, DIN Rail |
| Encapsulation | Box |
| Features | Auxiliary Contacts |
| Operating Temperature | 25°C ~ 60°C |
The stated contact form indicates a three-pole normally-open configuration suitable for switching three-phase loads. The coil power of 24.3 VA is consistent with standard S00-size contactor coils in the Siemens 3RT series.
Coil Characteristics
- Nominal coil voltage of 220 VAC at 50/60 Hz supply.
- Must-operate voltage of 187 VAC ensures dropout does not occur during momentary supply dips within normal supply tolerances.
- Operate time of 35 ms limits contact bounce during energization.
Contact Performance
- 9 A AC-3 current rating for standard motor-start duties.
- 3PST-NO (3 Form A) pole configuration.
- Box encapsulation provides basic environmental protection suitable for enclosed panel mounting.
Catalog Comparison
The following parts share the same base product number and 9 A contact rating but differ in coil voltage, auxiliary contact type, or packaging. All require independent engineering qualification.
| MPN | Coil Voltage | Must Operate | Coil Power | Contact Config | Encapsulation |
|---|---|---|---|---|---|
| 3RT20161AN21 | 220 VAC | 187 VAC | 24.3 VA | 1NO | Box |
| 3RT20161AN22 | 220 VAC | 187 VAC | 24.3 VA | 1NC | Box |
| 3RT20161AN61 | 200 VAC | 170 VAC | 26.4 VA | 1NO | Bulk |
3RT20161AN22 shares the same coil voltage and power consumption but substitutes a normally-closed auxiliary contact for the normally-open version.
3RT20161AN61 operates at a lower nominal coil voltage (200 VAC, 170 VAC must-operate) with slightly higher apparent power consumption (26.4 VA) and ships in bulk packaging rather than box.
Lower-similarity options (0.96) include 120 VAC, 208 VAC, 24 VAC, 400 VAC, and 480 VAC coil variants, all in the same S00 frame with 9 A contact ratings.
FAQ
What mounting options does the 3RT20161AN21 support?
The contactor supports both chassis mounting and standard 35 mm DIN rail attachment, allowing flexibility in panel layout.
What is the difference between the 1NO and 1NC contact configurations?
The 1NO primary poles serve the main load. The auxiliary contact provides a secondary normally-open or normally-closed signal path for control logic or interlock purposes; the selection depends on the circuit design requirements.
Is the 3RT20161AN21 suitable for reversing motor applications?
The 3PST-NO contact form supports standard across-the-line starting. Reversing duty typically requires auxiliary contactor logic or specific reversing variants; this should be verified against the specific application coordination requirements.