3RT2036 (size S2, 50 A)
Siemens (SIRIUS) · SIRIUS S2
S2-frame SIRIUS at 50 A AC-3 — 30 HP @ 460 V. Standard on European-built 22–30 kW screw compressors.
Ratings
- AC-3 (400 V)
- 50 A / 22 kW
- AC-1 (40 °C)
- 80 A
- Hp (3Φ)
- 15 HP @ 230 V · 30 HP @ 460 V
- Three-phase HP
- 15 HP @ 230 V · 30 HP @ 460 V
Coil data
- Available coil voltages
- 24, 110, 120, 200–220, 230, 240, 400, 480 VAC; 24 VDC; wide-range AC/DC options
- Inrush VA
- ≈ 200 VA
- Sealed (holding) VA
- ≈ 14 VA
- Pickup voltage
- 0.8–1.1 × Us
- Dropout voltage
- 0.3–0.6 × Us
Typical measured coil resistance (±15%, ballpark)
24 VAC≈ 3–8 Ω
120 VAC≈ 60–130 Ω
240 VAC≈ 260–520 Ω
480 VAC≈ 950–1,900 Ω
OL = open coil · near zero = shorted turns · coil-to-frame must read >1 MΩ.
Coil resistance checker
Pick the coil voltage, enter your meter reading across A1–A2 (coil disconnected), and compare it to the expected ballpark.
Ω
This model (24 VAC table value)3 Ω–8 Ω
Generic mid-frame 24 VAC4 Ω–9 Ω
OL = open coil. 0–2 Ω = shorted turns (often from a cooked transformer). Ballpark only (±15%+); electronic wide-range coils (e.g. ABB AF) read misleading values — test those at rated voltage instead. Always measure coil-to-frame too: must be >1 MΩ.
Terminals & accessories
Power/coil terminals: Box terminal to 35 mm²; ring-lug and spring-clamp variants
Auxiliary contacts: 1NO+1NC built in; 3RH29 front/side blocks expand to 8
Companion overload: 3RB thermal/electronic or 3RU2 thermal, direct-mount
Cross-references
- Schneider LC1D50
- WEG CWB50
- ABB AF52
- Allen-Bradley 100-C55
- Eaton XTCE050D
Field notes
- Spring-clamp (3RT2036-.A) variants hold better under compressor vibration than screw terminals — worth the upgrade on skid-mounted units.
- Solid-state coil versions read open on an ohmmeter; that is normal, not a failed coil.
- 3RB electronic overloads log the trip reason — read it before resetting instead of just cycling it.
Manufacturer documentation