GSK GSK988TA, Manual

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Chapter 3 MSTF Codes
165
Ⅰ
Programming
The first spindle of the CNC can execute 4-gear spindle speed, and the second spindle has
2-gear spindle speed. In executing S code, the system counts the analog voltage value
corresponding to the specified speed according to setting value(corresponding to No.3741
～
No.3744) of max. spindle speed (analog voltage is 10V)of current gear, and then outputs to
spindle servo or converter to ensure that the spindle actual speed and the requirement are the
same.
After the CNC is switched on, the analog output voltage is 0V. The analog output voltage is
reserved (except that the system is in cutting feed in the surface speed control mode and the
absolute value of X absolute coordinates is changed) after S code is executed. The analog
output voltage is 0V after S0 is executed. The analog output voltage is reserved when the system
resets and emergently stops.
When the spindle speed analog voltage control is valid, there are 2 methods to input the spindle
speed: the spindle fixed speed is defined by S code( r/min), and is invariant without changing S
code value, which is called constant speed control(G97 modal); other is the tangent speed of tool
relative to the outer circle of workpiece defined by S code, which is called constant surface speed
control (G96 modal), and the spindle speed is changed along with the absolute coordinates value
of X absolute coordinates in programming path when cutting feed is executed in the constant
surface speed.
3.2.2 Spindle Override
When the spindle speed analog voltage control is valid, the spindle actual speed can be tuned
real time by the spindle override and is limited by max spindle speed of current gear after the
spindle override is tuned, and it also limited by limited values of max. and min. spindle speed in
constant surface speed control mode.
The system supplies 8 steps for spindle override (50%
～
120% increment of 10%). The actual
steps and tune of spindle override are defined by PLC ladder and introductions from machine
manufacturer should be referred when using it. Refer to the following functions of GSK988TA/B
standard PLC ladder.
The spindle actual speed specified by GSK988TA/TB standard PLC ladder can be tuned
real time by the spindle override tune key at 8 steps in 50%
～
120% and it is not reserved when
the spindle override is switched off. Refer to the operations of spindle override in Ⅱ
OPERATION.
3.2.3 Multi-Spindle Control
GSK988TA/TB has a multi-spindle control function (controlling up to 3 spindles). Besides the 1st
spindle control, S code from CNC can control the 2nd and the 3rd spindle. The spindle code is the
same with the previous, using one S code. PLC sending a signal or address P code determines to
select one of 3 spindles.
Like the 1st spindle, the 2nd spindle and the 3rd spindle can execute 2-level gear switch.