Breakers for Motors

That answer is going to be dependent upon your local installation codes.

The breaker should be sized as close to the load as possible without causing nuisance tripping. The motor capacity is only peripherally associated with the breaker size, soft start notwhithstanding. The characteristic of the driven load is the critical issue; the current pulled through the starter and breaker and the time to full speed. A simple formula would necessarily oversize the equipment.

Breaker with a soft start? The smarter soft starts don't necessarily require a protection between it and the motor. With NFPA 70e, we've moved back to fuses and generally we protect the soft start inline with class J fuses at 150%.

The National Electrical Code governs circuit breaker size in the US. For instantaneous-trip breakers, the breaker may be rated up to 800% of motor full-load current; for inverse-time breakers, the breaker may be rated up to 250% of full-load current.

Rather than decoding your cryptic question, I will defer to you to make the decision as to whether or not the breaker you ask about will fit the criteria.

The CEC states that you can go as high as 1300% providing that you have followed the rules for motor cabling.

That has only to do with the instantaneous magnetic trips. Please refrain from making erroneous statements if you have no idea what you are referring to, it could lead to someone misusing their equipment and starting a fire!

That is why I posted the answer that it really depends on YOUR local code requirements. What I tell you for the US or someone else posts for Canada may mean absolutely nothing for someone in China or India or Lesotho. There are general guidelines that depend totally on the type of "breaker" being used, the available fault current, the design of the entire system etc. etc. etc., but the FIRST place to start is with the local jurisdiction that regulates electrical installations. What is acceptable in one area may be illegal in another.

I had exactly the same thoughts. I post only to endorse your statement.

I just thought that someone should mention that the Manufacturers do
publish the delay curves for their products and in the size and voltage
required some of these products are adjustible.