444
CHKCIR, CHKEND
When the GX Developer is used (High Performance model QCPU/Process CPU/Redundant CPU)
F
unct
i
on
CHKCIR, CHKEND
(1) The check ladder pattern that will be used in the CHK instruction can be updated to any format desired.
The actual failure checks are conducted with the CHKST and CHK instructions.
(2) Failure checks are conducted according to the check conditions designated by the CHK instruction and the ladder
pattern described between the CHKCIR and CHKEND instructions.
Remark
Refer to Page 440, Section 7.10.1 for more information on the CHKST and CHK instructions.
To change the check format of the CHK instruction using the CHKCIR to CHKEND instructions, the user should create a
ladder with index modification (Z0).
(a) The device numbers indicated at check conditions (X2 and X8 in the figure below) will assume index modification
values for the individual device numbers (with the exception of annunciators (F)) described in the ladder patterns.
X10 in the
in the figure below would be as follows:
However, the order in which failure detection is executed differs depending on whether SM710 is ON or OFF.
CHKCIR, CHKEND
Changing check format of CHK
7.10.2
CHKCIR, CHKEND
Setting
Data
Internal Devices
R, ZR
J \
U \G
Zn
Constants
Other
Bit
Word
Bit
Word
––
––
When corresponding to check condition X2 Processing performed by
.....
X12
When corresponding to check condition X8 Processing performed by
.....
X18
Bas
i
c
U
n
iv
ersa
l
L
CP
U
Process
High
performance
Redundant
SM
4
00
SM
4
00
L
adder
pattern
to
be
checked
Command
C
HK
S
T
C
HK
C
HK
C
I
R
C
HKEN
D
F
n
F
n
F
n
Refer
to
Max
.
9
co
il
s
CHKEND
CHKST
CHK
CHKCIR
X
X
X
X
Example