In a part program, what is the designated origin for coordinates?

In a part program, what is the designated origin for coordinates?

• A. Program zero
• B. Machine zero
• C. Work zero
• D. Reference zero

Answer: (A)

The coordinates in a part program are defined with respect to the program’s own origin, known as program zero. This point is set at the start of the program and serves as the reference for all X, Y, Z values that follow, letting the same code be reused with different part setups by applying work offsets as needed. Machine zero is the hardware home position of the axes, and work zero is the active work coordinate origin defined by offsets (like G54–G59) for the current setup. “Reference zero” isn’t a standard term for the origin in most CNC contexts. So the designated origin for coordinates in a part program is program zero.

The coordinates in a part program are defined with respect to the program’s own origin, known as program zero. This point is set at the start of the program and serves as the reference for all X, Y, Z values that follow, letting the same code be reused with different part setups by applying work offsets as needed. Machine zero is the hardware home position of the axes, and work zero is the active work coordinate origin defined by offsets (like G54–G59) for the current setup. “Reference zero” isn’t a standard term for the origin in most CNC contexts. So the designated origin for coordinates in a part program is program zero.