Six decimal places. Siemens CNC adopts 32-bit binary floating-point number, in which 23 bits are used to represent mantissa, 8 bits are used to represent exponent, and 1 bit is used to represent sign bit. In this representation, at most six significant digits can be represented. Siemens numerical control system is a numerical control system developed by Siemens in Germany, which is widely used in high-precision machining equipment such as machine tools, machining centers, laser cutting machines and water jet cutting machines. It is one of the most advanced numerical control systems in the world.