CWB25 (3-pole 25 A)
WEG · CWB 22–38 A frame (45 mm)
Mid-frame CWB covering 7.5–15 HP duty — very common as the line contactor in 10–15 HP rotary screw starters and as a wye contactor on larger sets.
Ratings
- AC-3 (440 V)
- 25 A
- AC-1 (resistive)
- 40 A
- Hp (3Φ)
- 7.5 HP @ 230 V · 15 HP @ 460 V
- Rated insulation
- 690 V
- Three-phase HP
- 7.5 HP @ 230 V · 15 HP @ 460 V
Coil data
- Available coil voltages
- 24, 110–120, 208–240, 380–415, 440–480, 550–600 VAC; 24 VDC; electronic wide-range option
- Inrush VA
- ≈ 110 VA
- Sealed (holding) VA
- ≈ 10 VA
- Pickup voltage
- ≥ 80% of rated
- Dropout voltage
- ≈ 30–60% of rated
Typical measured coil resistance (±15%, ballpark)
24 VAC≈ 5–11 Ω
120 VAC≈ 120–240 Ω
240 VAC≈ 500–950 Ω
480 VAC≈ 2,000–3,800 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)5 Ω–11 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 lug to 16 mm² / 6 AWG; coil A1/A2 front
Auxiliary contacts: 1 built-in NO or NC; front (2/4-pole) and side (1NO+1NC) blocks available
Companion overload: RW27D / RW67D thermal, 17–25 A dial typical
Cross-references
- Schneider LC1D25
- Siemens 3RT2026
- ABB AF26
- Allen-Bradley 100-C23
- Eaton XTCE025C
- Legacy WEG CWM25
Field notes
- Frequent short-cycling on a 15 HP screw will pit these tips fast — check for a leaking unloader or an undersized receiver before blaming the contactor.
- Measure coil resistance with one leg lifted; leaving the control circuit in parallel reads low and fools you into condemning a good coil.
- Tip wear of about ⅓ of original silver thickness is the practical replace point — pitting alone is normal.
WEG resources
Links go to the manufacturer's current catalog or product page — model-specific pages are often retired, so these stay live.
Manufacturer documentation