System Data; Basic Settings - Siemens SINUMERIK FM-NC Installation And Startup Manual

12.98 12.98
03.96
6.6

System data

6.6.1

Basic settings

Control time
The control operates according to time cycles which are defined via machine
cycles data. The basic system clock cycle is defined in seconds; the other time cycles
are calculated through multiplication with the basic system clock cycle.
The time cycles are set as standard to an optimum and should only be changed
if the requirements of the NC cannot be fulfilled with the preset values.
Table 6-5 Control time cycles
Machine data
MD 10050: SYSCLOCK_CYCLE_TIME
MD 10060:
POSCTRL_SYSCLOCK_TIME_RA TIO
MD 10070: IPO_SYSCLOCK_TIME_RATIO
Warning
!
If you have changed the time cycles, check that the operating response of the
control is correct in all operating modes before ending the start-up process.
Switchover from
A control system is switched over from the metric to an inch system by means
metric to inch of MD 10240: SCALING_SYSTEM_IS_METRIC (basic system metric, active
after power ON). The additional conversion factor is specified in MD 10250:
system
SCALING_VALUE_INCH (conversion factor for switchover to INCH system,
factor = 25.4). The existing data are converted to inches after power ON and
displayed. After switchover data must be entered in inches.
Setting MD 10260: CONVERT_SCALING_SYSTEM=1 in SW version 5 has
made it considerably easier to switch the dimension system over.
S
S
S
S
S
The basic programming setting (G70, G71, G700, G710) is switched over on a
channel-specific basis in MD 20150: GCODE_RESET_VALUES [12]. In the
case of softkey toggling via MMC, the value changes between G700 (inches)
and G710 (metric).
In SW version 5 and later, feedrates (inch/min or mm/min) are interpreted in the
dimension system in addition to length data in response to G700/G710.
 Siemens AG 2000 All Rights Reserved
SINUMERIK 840D Installation and Start-Up Guide (IAD) – 04.00 Edition
6 Assigning Parameters to the Control and the PLC Program
Name
Basic system
clock cycle
Factor for
position control
clock cycle
Factor for
interpolator clock
cycle
Availability of an MMC softkey in the "MACHINE" operating area for dimen-
sion system switchover.
Automatic conversion of NC active data when dimension system
is switched over.
Data back-up with current dimension system identifier.
Machine data MD 10240: SCALING_SYSTEM_IS_METRIC becomes active
on Reset.
The dimension system for sag compensation is configured in
MD 32711:CEC_SCALING_SYSTEM_METRIC.
6.6
NCU 571 NCU 572
= 0.0060 s ––> = 0.0040 s ––>
6 ms 4 ms
= 1 = 1 ∗ 6 ms = 1 = 1 ∗ 4 ms
= 6 ms = 4 ms
= 4 = 4 * 6 ms = 4 = 4 * 4 ms
=24 ms =16 ms
System data
NCU 573
= 0.0020 s ––>
2 ms
= 1 = 1 ∗ 2 ms
= 2 ms
= 4 = 4 * 2 ms
=8 ms
6-99
6