If you're buying a replacement AC contactor, the three numbers to settle first are coil voltage, pole count, and amp rating. The four contactors here span two coil voltages (24VAC and 110/120VAC), two pole counts (2-pole and 3-pole), and two current ratings (30A and 40A), with listed prices from $22.99 to $36.40.
Quick take
Two Shopcorp units are 40A 2-pole definite-purpose contactors, one with a 24VAC coil and one with a 110/120VAC coil; both sit at the lower end of the range. The 3-pole 40A 24VAC coil contactor is the only three-pole option and sits at the top. The remaining contactor is a 2-pole 30A 24VAC coil unit for lower-current 24V replacement jobs.
What changes when you pick a contactor
Coil voltage must match the control circuit you are connecting to: 24VAC for a low-voltage control setup, 110/120VAC for a line-voltage coil. Pole count follows the circuit: 2-pole units switch two-wire loads, while the 3-pole unit adds one more pole. Amp rating is the capacity gate: 30A for smaller motor loads, 40A for the heavier end here.
Listed price comparison
| Option | Listed price | Bar |
|---|---|---|
| 2 Pole 30 Amp 24 VAC Coil AC contactor 2P 30A 24V 50/60Hz AC Motor Contactor | USD 24.99 | |
| 3 Pole 40 Amp 24 VAC Coil AC Contactor 3P 40A 24V 50/60Hz AC Motor Contactor Re | USD 36.40 | |
| AC Contactor 40 Amp 50 RES 2 Pole 24VAC Coil - Definite Purpose UL Listed | USD 22.99 | |
| AC Contactor 40 Amp 50 RES 2 Pole 110/120VAC Coil - Definite Purpose UL Listed | USD 22.99 |
The four listed prices cover a $13.41 spread. The two Shopcorp definite-purpose contactors share the $22.99 price point. The 30A 2-pole 24V contactor sits at $24.99, and the 3-pole 40A 24V contactor is at $36.40.
Decision matrix
| Your need | Consider |
|---|---|
| 2-pole, 30A, 24VAC coil | 2 Pole 30 Amp 24 VAC Coil AC contactor 2P 30A 24V 50/60Hz AC Motor Contactor |
| 3-pole, 40A, 24VAC coil | 3 Pole 40 Amp 24 VAC Coil AC Contactor 3P 40A 24V 50/60Hz AC Motor Contactor Re |
| 2-pole, 40A, 24VAC coil, UL Listed | AC Contactor 40 Amp 50 RES 2 Pole 24VAC Coil - Definite Purpose UL Listed |
| 2-pole, 40A, 110/120VAC coil, UL Listed | AC Contactor 40 Amp 50 RES 2 Pole 110/120VAC Coil - Definite Purpose UL Listed |
Contactors at a glance
2 Pole 30 Amp 24 VAC Coil AC contactor 2P 30A 24V 50/60Hz AC Motor Contactor
This is the lower-current choice in the set. Its 2-pole format and 24VAC coil keep it parallel to the Shopcorp 40A 24V unit, but the FLA rating drops to 30A, so it matches systems that do not need 40A capacity. The listed attributes call out copper terminal contacts and a copper coil for conductivity, plus a flame-retardant shell. The temperature range runs from -40°C to +65°C. The limitation is capacity: if your contactor needs 40A, this 30A unit is not designed to handle it and you would need one of the 40A options instead.
3 Pole 40 Amp 24 VAC Coil AC Contactor 3P 40A 24V 50/60Hz AC Motor Contactor Re
This is the only three-pole unit in the lineup, and it carries the top listed price. It pairs a 24VAC coil with a 40A FLA rating and includes copper terminal contacts plus a copper coil. If your application needs 3-pole switching, neither of the 2-pole contactors can fill that role, so this is the matched option. The trade-off is the price: it sits above the two 40A 2-pole units by more than $13. If the circuit only requires two poles, the additional pole is unnecessary and the lower-priced 2-pole 40A options become the more direct fit.
AC Contactor 40 Amp 50 RES 2 Pole 24VAC Coil - Definite Purpose UL Listed
This Shopcorp contactor is the 24VAC coil version of the 40A 2-pole definite-purpose design. The title's 50 RES points to a 50A resistive/incandescent load rating, while the 40A rating covers inductive and motor loads; the AC-1 and AC-3 ratings point to air conditioners, compressors, and fans. It is UL Listed, and the country of origin is given as the United States. The limitation is the 2-pole format. A 3-pole system needs the 3-pole unit, and a 110/120V control circuit needs the sibling listed with that coil.
AC Contactor 40 Amp 50 RES 2 Pole 110/120VAC Coil - Definite Purpose UL Listed
This Shopcorp contactor shares the 40A definite-purpose format, but the coil is built for a 110/120VAC circuit instead of 24VAC. It keeps the 50A resistive load rating and 40A motor load rating, is UL Listed, and is aimed at heating, refrigeration, lighting, and HVAC tasks. The country of origin is listed as China. The limitation is coil compatibility: with a 110/120V coil, this unit is not intended for a 24V control circuit. If your system uses a 24V coil, choose the 24VAC version.
Final recommendation by use case
Go with the 3 Pole 40 Amp 24 VAC Coil AC Contactor when you need three poles and a 40A rating. Choose the AC Contactor 40 Amp 50 RES 2 Pole 24VAC Coil for a 40A 2-pole replacement with a 24V control coil, especially if you want the lower-priced end of the range. Pick the AC Contactor 40 Amp 50 RES 2 Pole 110/120VAC Coil when the control circuit runs at line voltage. Select the 2 Pole 30 Amp 24 VAC Coil AC contactor when 30A capacity is enough and you want a 2-pole 24V replacement.
