CWBN NEMA Size 1 (27 A)

WEG · NEMA · 3-pole

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CWBN NEMA Size 1 (27 A)

WEG · CWBN NEMA size 00–3 range

WEG's NEMA-rated version of the CWB platform — sizes 00 through 3, up to 95 A. Size 1 is the direct drop-in when replacing a Square D 8502 or Allen-Bradley 509 in an older shop panel.

Ratings
NEMA size
1 (27 A continuous)
Hp (3Φ)
7.5 HP @ 230 V · 10 HP @ 460/575 V
Hp (1Φ)
2 HP @ 115 V · 3 HP @ 230 V
Single-phase HP
2 HP @ 115 V · 3 HP @ 230 V
Three-phase HP
7.5 HP @ 230 V · 10 HP @ 460 V
Coil data
Available coil voltages
24, 120, 208, 240, 480, 600 VAC 60 Hz
Inrush VA
≈ 180 VA
Sealed (holding) VA
≈ 15 VA
Pickup voltage
≈ 85% of rated
Dropout voltage
≈ 40–65% of rated
Typical measured coil resistance (±15%, ballpark)
24 VAC≈ 4–9 Ω
120 VAC≈ 90–190 Ω
480 VAC≈ 1,500–3,000 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)4 Ω9 Ω
Generic small-frame 24 VAC8 Ω16 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: NEMA-spaced line/load terminals, 14–4 AWG
Auxiliary contacts: 1 NO standard; add-on NEMA-style aux blocks available
Companion overload: Bimetallic or eutectic NEMA overload block; heater sized to nameplate FLA
Field notes
  • NEMA sizing is horsepower-based with built-in margin, so a Size 1 outlasts an IEC 25 A in the same duty — worth the extra panel space on hard-starting recips.
  • Panel bolt spacing differs slightly from Square D 8502 — carry a back-plate adapter or drill new holes.
  • Keep the correct heater element table with the unit; the wrong heater is the most common nuisance-trip cause after a NEMA starter swap.
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