I'm installing a dedicated circuit for a portable arc welder. The min. rating is 15 amps at 120 volts and the max is 20 amps at 120 volts. Article 630-12 state that the OCP shall not be more than 200% of the max. My question is, what would be optimal? Should I install a 20 amp OCPD based off the MAX on the nameplate of the welder or should I use the Maximum stated by the NEC?

This kind of confused me because the code states no minimum only a maximum.

I believe that if the nameplate specified a 20A max OCPD, thats what I would use.