Okay, this is a good problem. Let's break it down step-by-step, focusing on NEC compliance and best practices for a machine like this.

Understanding the Information 30kW (40.3 HP) Main Motor

This is the largest single load and will dictate the OCPD size, primarily.

Full Load Amps (FLA) 180A

This is the total current draw the machine is expected to pull under normal operating conditions with all components running at their rated capacity.

Nominal Current 120A

This is the oddball. "Nominal" typically means "typical" or "expected average." The manufacturer is telling you that under typical use, the machine will likely draw closer to 120A than 180A. This is still the metal-dab shop, so I would definitely NOT plan for this. The key is the FLC rating.

Made in Turkey

This isn't necessarily bad, but it means extra scrutiny is wise to ensure compliance with US electrical standards, especially regarding documentation and ratings.

No VFD on Main Motor

Important! Full inrush current considerations are required.

NEC Considerations & Calculations1. Conductor Sizing (NEC 430.22)

The conductors supplying a single motor must be sized at a minimum of 125% of the motor's full-load current. However, since this is the entire machine's load, and it has the FLA as a complete unit, let’s use that. 180A 1.25 = 225A. You need conductors rated for at least 225 amps. You will likely need to run parallel conductors to meet this, or use a very large single conductor, depending on your installation requirements.2.

Overcurrent Protection Device (OCPD) Sizing (NEC 430.52)

This is where the motor HP comes into play. NEC 430.52 dictates the maximum OCPD size based on the motor's type, voltage, and starting method. Since you have no VFD and it's likely a standard induction motor, we'll use the more generous settings for inverse time breakers.

Refer to NEC Table 430.52

For a standard induction motor (design letter B, C, or D – check the motor nameplate), an inverse time breaker can be up to 250% of the motor's FLA.

Find the Motor FLA

We need to convert the motor's HP to amps. NEC Table 430.250 gives full-load currents for 3-phase AC motors. You'll need to know the voltage of the motor (e.g., 208V, 480V). Let's assume it's 480V for this example. A 40 HP, 480V motor has an FLA of approximately 52 Amps (from Table 430.250). Your actual value may be slightly different.

Calculate Max OCPD

52A 2.50 = 130 Amps.

However

NEC 430.52(C)(1)(1) allows you to go to the next higher standard breaker size if the calculated size doesn't match a standard size.

Consider Total Load

The 180A FLA must be protected. A 300A breaker is too large to protect the conductors if an overcurrent situation occurs.3.

Short-Circuit Current Rating (SCCR)



CRITICAL

You must determine the SCCR of the machine and the available fault current at the point of connection. The machine's SCCR must be equal to or greater than the available fault current. This is for safety to prevent catastrophic failure during a fault. This information should be on the machine’s nameplate.4.

Service Disconnect (NEC 430.109)

The disconnecting means must be horsepower rated. A 40HP rated disconnect should be sufficient. It also needs to have an amperage rating at least equal to 115% of the full-load current. 180A 1.15 = 207 Amps A 40HP, 200A, 3-pole disconnect switch would satisfy this.

Recommendations1. Clarify "Nominal Current"

Contact the manufacturer directly and ask exactly what they mean by "Nominal Current." Is it a typical operating current? Is it a minimum running current? This is important. However,

base your calculations on the FLA.2. Verify Voltage and Motor Information

Get the exact voltage and design letter (A, B, C, D) from the motor nameplate. This will allow you to accurately determine the motor FLA from Table 430.250.
3.

Nameplate Scrutiny

Carefully examine the machine's nameplate for SCCR, voltage, phase, and any other relevant information.4.

Conservative Approach

Given the unclear "nominal current," it's best to be conservative. Wire for the 180A FLA, plus the 25% safety margin (225A minimum conductor ampacity).5.

Parallel Conductors/Large Conductor

You'll need to consider using parallel conductors or a single large conductor to achieve the 225A minimum ampacity. Ensure the parallel conductors are the same length, material, size, and terminated in the same manner.6.

OCPD

Based on the above calculations, and assuming a 480V motor, a breaker rated to 130 amps will cover your over current situation. Keep in mind it needs to also protect the conductors. A 250 amp breaker would likely be a good option to handle the over current and protect the conductors in question.7.

Local Codes

Always check with your local electrical inspector for any additional requirements or interpretations of the NEC.

Important Notes Safety First

Electrical work is dangerous. Always de-energize circuits before working on them, follow proper lockout/tagout procedures, and use appropriate PPE.

Qualified Electrician

This advice is for informational purposes only. This work should be performed by a licensed and qualified electrician who understands the NEC and local codes.

Documentation: Keep thorough documentation of all calculations, nameplate information, and wiring diagrams for future reference and inspection.By taking a careful, methodical approach and double-checking all your calculations, you can ensure a safe and code-compliant installation for this shear. Good luck! Flag for review