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Velocities, Setpoint/Actual Value Systems, Closed-Loop Control (G2)
7.2 Metric/inch measuring system
Turning, Milling, Nibbling
Function Manual, 11/2012, 6FC5397-1CP10-5BA0
119
7.2.1
Conversion of basic system by part program
When programming, it is possible to change over between dimension systems for some
workpiece-related specifications with G70/G71 and with G700/G710. Data influenced by
G70/G71/G700/G710 is described in the Programming Guide.
When changing the dimension system via HMI softkey, these initial settings are
automatically initialized for the dimension system with G700 or G710.
Application
With this function it is possible, for example, with a metric basic system, to machine an inch
thread in a metric part program. Tool offsets, zero offsets and feedrates remain metric.
Machine data is displayed on the screen using the basic system selected in MD10240
SCALING_SYSTEM_IS_METRIC (metric basic system).
Machine coordinates, tool data and zero offsets are always displayed in the initial state,
workpiece coordinate displays are in the current setting.
Note
If programs including data sets (zero offset, tool offset) programmed in the measuring
system, which differs from the basic system, are read in from an external source, the initial
state must first be changed via machine data MD10240 SCALING_SYSTEM_IS_METRIC.
Data exchange with the PLC of interface signals containing dimension information, e.g.
feedrate for path and positioning axes, is always carried out in the selected basic system.
G700/G710 extends the functionality of G70/G71 as follows:
1.
The feedrate is interpreted in the programmed measuring system:
–
G700: length parameters [inch]; feedrates [inch/min]
–
G710: length parameters [mm]; feedrates [mm/min]
The programmed feed is modal and therefore remains active after subsequent
G70/G71/G700/G710 commands. If the feedrate is to apply in the new
G70/G71/G700/G710 context, it must be re-programmed.
2.
System variables and machine data specifying lengths in the part program are read and
written in the programmed measuring system.
This allows you to implement part programs that are independent of the current default
measuring system.
Comparison of the effect of G70 and G700 on machine data and system variables in the part
program:
●
with G70: reading/writing in the basic system
●
with G700: reading/writing in the programmed measuring system