Is a Siemens class b machine a return?

Yes. According to checking the official website of Siemens, the b class machine is a rebuilt or substandard machine, which is officially refurbished by itself and also quality checked. Siemens is a focused technology company, with innovations in electrification, automation and digitalization, providing solutions for customers in the areas of power generation and transmission and distribution, infrastructure, industrial automation, drives and software.