Siemens 3RT20282AM20 Contactor (S0, 38A, 208VAC Coil)
3RT20282AM20 — 208VAC Coil Variant (vs. 230VAC / 110VAC Options)
The 3RT20282AM20 is one of several S0-size contactors sharing the same base number with differing coil voltages. Coil selection determines must-operate thresholds across regions.
| Spec | 3RT20282AM20 (seed) | 3RT20282AL20 | 3RT20282AG20 |
|---|---|---|---|
| Coil Voltage | 208VAC | 230VAC | 110VAC |
| Must Operate Voltage | 176.8 VAC | 195.5 VAC | 93.5 VAC |
| Contact Rating | 38 A | 38 A | 38 A |
| Mounting | Chassis, DIN Rail | Chassis, DIN Rail | Chassis, DIN Rail |
| Contact Form | 3PST-NO (3 Form A) | 3PST-NO (3 Form A) | 3PST-NO (3 Form A) |
| Coil Power | 79VA | 79VA | 79VA |
| Operate Time | 40 ms | 40 ms | 40 ms |
The 230VAC variant (3RT20282AL20) uses the same 79VA coil and 40ms timing; must-operate scales with nominal voltage. The 110VAC version (3RT20282AG20) targets lower-voltage control circuits while preserving the 38A main-contact rating.
Contact and Mechanical Summary
- Main contacts: 3PST-NO (three independent Form A poles) rated 38A
- Auxiliary: integrated 1NO/1NC for control-circuit interlock
- Enclosure: box-style; operating temperature 25°C to 60°C
- Mounting: chassis or DIN rail (35mm)
All variants in the 3RT2028 family share identical contact arrangement, operate time (40ms), and mounting footprint—differing only in coil voltage and corresponding must-operate threshold.
Engineering Verification Checklist
- Confirm control-system nominal voltage matches coil rating (208VAC)
- Verify must-operate voltage (176.8 VAC) accommodates expected line dips under load
- Check that 38A contact rating suits motor FLA and short-circuit coordination plan
- Validate DIN rail clearance and terminal torque specifications for panel layout
- Confirm auxiliary contact logic (1NO/1NC) matches interlock or status-feedback requirements
- Verify coil power draw (79VA inrush) does not exceed control-transformer or power-supply capacity
- Ensure enclosure box style compatible with environmental ingress requirements