Siemens SINUMERIK 840D sl Function Manual page 472

K1: Mode group, channel, program operation, reset response
9.5 Program test
Activation
The function is activated via interface signal:
DB21, ... DBX1.7 (activate program test)
Display
The corresponding field on the operator interface is reversed and the interface signal in the
PLC as a checkback of the active program test:
DB21, ... DBX33.7 (program test active)
Program start and program run
When the program test function is active, the part program can be started and executed (incl.
auxiliary function outputs, wait times, G function outputs etc.) via the interface signal:
DB21, ... DBX7.1 (NC-Start)
The safety functions such as software limit switch, working area limits continue to be valid.
The only difference compared to normal program operation is that an internal axis disable is
set for all axes (including spindles). The machine axes do not move, the actual values are
generated internally from the setpoints that are not output. The programmed velocities remain
unchanged. This means that the position and velocity information on the operator interface is
exactly the same as that output during normal part program execution. The position control is
not interrupted when this function is active, so the axes do not have to be referenced when
the function is switched off.
The signals for exact stop:
DB31, ... DBX60.6/60.7 (exact stop coarse/fine)
mirror the actual status on the machine.
They are only canceled during program testing if the axis is pushed out of its set position (the
set position remains constant during program testing).
With signal:
DB21, ... DBX33.7 (program test active)
both the PLC program and the part program can use variable $P_ISTEST to decide how to
react or branch in response to these signals during testing.
Note
Dry run feedrate
"Program execution without axis motion" can also be activated with the function "Dry run
feedrate". With this function, part program sections with a small programmed feedrate can be
processed in a shorter time.
472
CAUTION
Function Manual, 01/2015, 6FC5397-0BP40-5BA2
Basic Functions