According to DIN 66217, clockwise, rectangular (Cartesian) coordinate systems are used in machine tools. The following coordinate systems are defined:
Machine coordinate system MCS The machine coordinate system is formed by all the available physical machine axes.
Basic coordinate system BCS The basic coordinate system consists of 3 Cartesian axes (geometry axes), as well as other non-geometry axes (special axes).
BCS and MCS are always in conformance when the BCS can be mapped to the MCS without kinematic transformation (e.g. TRANSMIT/face transformation and max. 3 machine axes).
Basic zero system BZS DRF offsets, external work offsets and basic frames map the BCS on the BZS.
Settable zero system SZS An activated settable work offset G54 to G599 transfers the BZS to the SZS.
Workpiece coordinate system WCS The programmable frame determines the WCS representing the basis for programming.
Work offsets are therefore used to transform the machine zero point into the workpiece zero point in order to simplify programming.
The following work offsets are possible:
Settable work offsets: It is possible to enter up to 100 work offsets (G54 to G57, G505 to G599), offset coordinates, angles and scaling factors in order to call zero points program-wide for various fixtures or clamping operations, for example. The work offsets can be suppressed block-by-block.
Programmable work offsets: Work offsets can be programmed with TRANS (substitution function, basis G54 to G599) or ATRANS (additive function). This allows you, for example, to work with different work offsets for repetitive machining operations at different positions on the workpiece. G58/G59 make previously programmed work offsets axially replaceable.
External work offsets: Axis-related linear work offsets can also be activated via the PLC user software (function blocks) with assignment of system variable $AA_ETRANS [axis].