Siemens SINUMERIK 840C - Manual (Page 791)

12 Functional Descriptions 11.92
12.5 Warm restart
12.5 Warm restart
12.5.1 Corresponding data
• NC MD 360* (Axis valid in BAG)
• NC MD 316* (Pointer for leadscrew error comp.)
• NC MD 320* (Pointer for leadscrew error comp.)
• NC MD 453* (Spindle valid in BAG)
• NC MD 876 to 899 (Coupled axis groupings)
• NC MD 5156 to 5183 (Coupled motion combinations)
• NC MD 5060 to 5139 (Transformation data blocks)
• Signal DB 48 DL 0 bit 0 (Initiate warm restart)
• Signal DB 48 DR 1 bit 0 (Terminate warm restart)
• Alarm nos. 70 to 80
12.5.2 Functional description
On some machines, it is necessary to assign arbitrary axes to a different mode group without
having to shut down the control, which would result in loss of the reference point.
Example
A machine has two working areas:
Area I with axis B'
Area II with axes B1'.
To ensure effectivity, the working areas are subdivided into different mode groups.
The three main axes (X, Y and Z) are assigned separately to working area I (mode group 1) or
working area II (mode group 2) over a warm restart. This necessitates use of a separate
machine control panel for each working area; main axes X, Y and Z are allocated to each
control panel.
The machine data can also be modified with @ functions by invoking a PLC cycle in a free
channel. A warm restart is required to modify the machine data listed in 12.3.1.
When working area I is in use, the three main axes (X, Y and Z), axis B', and the spindle are
allocated to machine control panel 1 and mode group 1.
Axes B1' can be traversed in JOG mode in working area II to load and unload a workpiece.
If the working areas are to be reversed, i.e. if working area II is to be used to machine a
workpiece and working area I for loading and unloading, the axis assignments must be
changed, i.e. there must be a switch to another mode group. When this switch takes place,
the axes are reassigned to the machine control panels.
An auxiliary function is assigned to each working area to help switch mode groups. The
relevant auxiliary function provides the information which the PLC needs to reassign the axes
and to make any necessary changes in the machine data. Once the machine data has been
modified, a warm restart (DB48, DL0, bit 0) must be initiated over the PLC interface. The
"warm restart" function reconfigures the control without necessitating subsequent
reapproaching of the reference points.
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SINUMERIK 840C (IA)