CR306 (NEMA Size 1, 27 A)
GE / ABB (300-Line) · NEMA Size 1
GE's 300-Line magnetic starter — decades of these are still in service in plants that bought GE switchgear. Now supported by ABB after the GE industrial acquisition.
Ratings
- Continuous current
- 27 A
- 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 @ 460/575 V
Coil data
- Available coil voltages
- Coil suffixes: 02 = 115/120 V · 03 = 230/240 V · 04 = 460/480 V
- Inrush VA
- ≈ 200 VA
- Sealed (holding) VA
- ≈ 24 VA
- Pickup voltage
- ≥ 85% of rated
- Dropout voltage
- ≈ 40–65% of rated
Typical measured coil resistance (±15%, ballpark)
120 VAC (…02)≈ 50–90 Ω
480 VAC (…04)≈ 800–1,400 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 (120 VAC (…02) table value)50 Ω–90 Ω
Generic small-frame 110–120 VAC150 Ω–450 Ω
Readings 2× high usually mean heat damage and a coil near end of life. 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: L1–L3 top, T1–T3 bottom; coil front
Auxiliary contacts: CR205X aux contact kits
Companion overload: CR123C/CR324 heater-type overloads
Cross-references
- Square D 8536 Size 1
- Allen-Bradley 509 Size 1
- Eaton AN16DN0
- Siemens Class 14 Size 1
Field notes
- CR123 heater elements size by motor FLA from the table inside the enclosure door — the table belongs with the starter; replace it if missing.
- ABB still supports renewal parts; aftermarket heaters (Furnas/Siemens H-series) often interchange dimensionally but verify trip curves.
GE / ABB (300-Line) resources
Links go to the manufacturer's current catalog or product page — model-specific pages are often retired, so these stay live.