Here what I found.
The soft start can make a compressor last longer by reducing the initial stress and electrical surges during startup. It does this by gradually increasing the power to the compressor instead of delivering a sudden, hard jolt of electricity, which minimizes wear and tear on the compressor and other components.
A 24-amp startup reading for a Trane AC compressor with a soft start added is likely normal and an expected outcome of using the device.
Soft starters are designed to significantly reduce the high inrush current (locked rotor amps, or LRA) that compressors typically draw on startup, which can often be 3 to 6 times their normal running load amps (RLA). The 24-amp reading indicates a successful reduction from a much higher potential LRA.
Here are some context points to consider:
Typical Reduction: Soft starters can reduce startup amperage by 55% to 75%. For example, one user reported their 4-ton unit's startup amps dropped from 76 amps to 24 amps after installing a soft start.
Running Amps: A typical central AC unit has running amps (RLA) between 15 to 45 amps, depending on its size (tonnage). A 24-amp startup reading is often close to or slightly above the unit's normal running amperage, which is the goal of a soft start.
[This message has been edited by CoolBlue87GT (edited 11-05-2025).]