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GSK218MC Series Machining Center CNC System PLC & Installation Connection Manual
10
Volume I
Programming
The machine tool input register is scanned and memorized its input signal from the machine
each 8ms. The 1
st
level program is also performed the corresponding treatment by using this signals
directly.
(3) The 2
nd
level program input latch
The 2
nd
level program input signal latch is also called the 2
nd
level program synchronic input
signal register. Wherein, the stored input signal is treated by the 2
nd
level program. This signal state
in the register is synchronic with the 2
nd
level one.
The signals both in the NC and machine tool input latch can be locked to the 2
nd
level program
input latch, as long as the 2
nd
level program performs. The signal state in this latch keeps invariable
during the performance of the 2
nd
level program.
2.5.2 Treatment of the Output Signal
(1) NC output register
The output signal transfers to the NC output register from the PLC each 8ms.
(2) Machine tool output register
The signal memorized in the machine tool output register conveys to the machine tool each
8ms.
Note:
The signal states, such as the NC input register, NC output register, machine input register and machine
output register, which can be displayed by the self-diagnosis function. The diagnosis number is the address
number in the sequence programming.
2.5.3 Distinguish of Signal State Between 1
st
Level and 2
nd
Program
As for the same input signal, their states may different between the 1
st
and 2
nd
level
programming, that is the reason that different registers are used between two levels programming.
Namely, the input signal used with the 2
nd
level program is the one of the 1
st
level who is locked. And
therefore, the signal in the 2
nd
level program is later than the 1
st
level one. At the worst case, one 2
nd
level program performance cycle can be lagged.
It is better to remember this point when programming the ladder diagram.
