When you're shopping for soft starters and motor controls, the first question isn't which model is best - it's which class of starter actually matches the motor you're trying to control. A compact single-phase soft starter and a large reduced-voltage autotransformer starter both fall under the "soft starter" umbrella, but they serve completely different loads. This head-to-head compares an AC 220V single-phase soft starter listed at $48.59 with a Square D Size 5 200 HP autotransformer soft starter listed at $4,750.00.
Quick verdict
If you need gentle startup for a small single-phase motor, the compact soft starter is the clear budget pick. If you're starting a 200 HP motor in an industrial setting, the Square D Size 5 is the one that belongs in the conversation. The price gap is roughly $4,700, and that gap reflects a huge difference in physical size, current rating, and intended application.
| Product | Listed Price | Condition | Best For |
|---|---|---|---|
| AC 220V Single-Phase Soft Starter | $48.59 | New | Small single-phase motors, adjustable soft-start behavior |
| Square D Size 5 200 HP Autotransformer Soft Starter | $4,750.00 | Used | Big 200 HP motors needing reduced-voltage starting |
Where the compact soft starter wins
The single-phase soft starter is dramatically less expensive and comes in new condition. It's designed for smaller motor loads, and the adjustment potentiometers let you set the starting voltage and soft-start time to match the motor's behavior. If your motor is in the small single-phase category, this is a practical way to add soft starting without reworking an entire control panel.
Where the Square D Size 5 wins
The Square D unit is built for an entirely different scale of motor. With a 200 HP rating and 250A frame, it uses autotransformer reduced-voltage starting to bring a large motor up to speed smoothly. The Size 5 form factor tells you this is industrial equipment meant to be installed in a serious motor control setup. Used condition is a caveat, but for the right 200 HP application, the capacity is what matters.
Product notes
AC 220V Single-Phase Soft Starter
If you have a small single-phase motor and a tight budget, this starter gives you an adjustable soft-start curve without spending much. The potentiometers control the starting voltage and the soft-start time, so you can tune the ramp instead of settling for a fixed behavior. It's listed as new, which means you're not dealing with previous installation wear. The main limitation is its scale: it's aimed at single-phase AC 220V applications, not the kind of high-current, three-phase industrial loads you'd find on a 200 HP motor. If your motor is bigger than that, this compact unit simply isn't the right tool.
Square D Size 5 200 HP Autotransformer Soft Starter
This is the heavy-duty end of the soft-starter spectrum. The Square D Size 5 class, 250A rating, and 200 HP autotransformer design are what you look for when you need reduced-voltage starting on a large motor. The autotransformer approach limits inrush current during startup, which is critical on big equipment. The used condition is the trade-off, and anyone installing it should account for that in their purchasing decision. For a facility that already runs Square D motor control hardware, this unit is a natural fit. Given its scale, it's a serious purchase rather than a casual one.
Final choice by use case
Pick the AC 220V single-phase soft starter if you have a small motor, want adjustable starting behavior, and don't need to control hundreds of amps. Pick the Square D Size 5 200 HP autotransformer starter if you have a large 200 HP motor and need industrial-grade reduced-voltage starting, with the understanding that it's a used component. Both are valid soft starters - they're just solving different problems.
