The buying decision
Choosing a soft starter comes down to the motor you need to start. One option is a used Square D Size 5 Reduced Voltage Motor Soft Starter 200 HP Autotransformer 250A priced at USD 4,750.00. The other is a new 16-32A AC Soft Starter w/ Reverse Motor Protection For 4-7 Ton AC Install Kit priced at USD 120.89. Both reduce starting current, but they are built for completely different motor sizes.
Quick verdict
Pick the Square D Size 5 when you're managing a large industrial motor and need the capacity that only a high-power starter can provide. Pick the 16-32A AC Soft Starter when you're working on a residential 4-7 ton air conditioner or equipment like an EV charger, generator, or solar power setup. The choice really depends on the current and horsepower you're dealing with.
Price and capacity comparison
| Product | Capacity | Current | Condition | Price |
|---|---|---|---|---|
| Square D Size 5 Reduced Voltage Motor Soft Starter 200 HP Autotransformer 250A | 200 HP | 250 A | Used | USD 4,750.00 |
| 16-32A AC Soft Starter w/ Reverse Motor Protection For 4-7 Ton AC Install Kit | 4-7 ton AC units | 16-32 A | New | USD 120.89 |
Where each product wins
The Square D Size 5 wins for industrial applications that demand reduced-voltage starting on a large scale. It uses an autotransformer design, and the high current rating puts it in a different class than the compact starter.
The 16-32A AC Soft Starter wins for home and light-commercial use. It's new, includes an install kit, works with HVAC systems and other compatible devices, and adds reverse motor protection that can help prevent low-voltage and over-current compressor trouble.
Product notes
#### Square D Size 5
This starter is the heavyweight option. It's designed for reduced-voltage motor starting in high-capacity settings, with enough current capacity for demanding equipment. The autotransformer approach is a solid fit for large motors that need a gradual ramp rather than a hard electrical jolt. It is a used unit, so you're getting industrial capability rather than a fresh-out-of-the-box consumer product. The price is substantial, and the starter is not intended for residential 4-7 ton AC applications. If your motor isn't in that industrial class, this is more than you need. In short, buy it for high-horsepower, high-current jobs only.
#### 16-32A AC Soft Starter
This is the practical pick for a typical residential AC system. It's sized for most air conditioning units between 4 and 7 tons, and it's also compatible with HVAC systems, EV chargers, generators, and solar power. The reverse motor protection handles low-voltage and over-current situations, and the gradual voltage ramp reduces the inrush current that can cause generator flicker or tripped breakers. It comes with a 1-year manufacturer warranty and a new install kit. The limitation is scale: it's not built for a high-horsepower industrial motor, so its current range is limited.
Final choice by use case
- For an industrial motor that needs reduced-voltage starting, go with Square D Size 5.
- For a residential AC system and generator compatibility, go with the 16-32A AC Soft Starter.
