509 Series (NEMA Size 1, 27 A)
Allen-Bradley (Rockwell) · NEMA Size 1
Bulletin 509 full-voltage starter — the AB counterpart to Square D's Type S. Same NEMA Size 1 ratings; when fitted with the overload block it's a complete starter, without it's a 500/505 contactor.
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: D = 110/120 V · B = 24 V · F = 220/240 V · A = 440/480 V
- Inrush VA
- ≈ 218 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≈ 50–90 Ω
480 VAC≈ 750–1,300 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 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 terminals marked on the label
Auxiliary contacts: 595 aux contact kits (NO/NC), field-addable
Companion overload: 592 eutectic alloy or 592-JOV16 solid-state overloads
Cross-references
- Square D 8536 Size 1
- Eaton AN16DN0
- Siemens/Furnas Class 14 Size 1
- GE CR306
Field notes
- Eutectic (solder-pot) overloads must cool before reset — a hot one that won't reset in 60 s isn't broken, it's doing its job.
- Heater elements size off motor nameplate FLA and ambient; don't guess from the old heater — verify the motor first.