Mitsubishi MELSEC-Q/L Programming Manual page 448

CHKCIR, CHKEND
(g) The annunciators (F) used in the CHK instruction do not actually turn ON/OFF. Even when they are monitored from
an external device, the ON/OFF status cannot be checked.
(h) A ladder pattern can be created up to 256 steps.
Further, OUT F
(3) Coil numbers for ladders designated with the CHKCIR through CHKEND instructions are allocated coil numbers from 1
to 9, from top to bottom.
(4) The CHKCIR and CHKEND instructions can be written at any step in the program desired.
It can be used in up to two locations in all program files being executed.
However, the CHKCIR and CHKEND instructions cannot be used in more than 1 location in a single program file.
(5) The CHKCIR and CHKEND instructions cannot be used in low speed execution type programs.
If a program file in which the CHKCIR or CHKEND instruction is described is set as a low speed execution type program,
an operation error will occur, and the High Performance model QCPU/Process CPU/Redundant CPU operation will be
suspended.
Operation Error
(1) In any of the following cases, an operation error occurs, the error flag (SM0) turns ON, and an error code is stored into
SD0.
Error
code
The CHKEND instruction is not executed after the CHKCIR instruction.
4230 The CHKEND instruction is executed when no CHKCIR instruction has
been executed.
The CHKCIR or CHKEND instruction appears three or more times in all
program files.
The CHKCIR or CHKEND instruction appears two or more times in a
single program file.
The CHKST and CHK instruction are used in a low speed execution
4235 type program.
There are 10 or more F instances in a ladder pattern.
The ladder pattern has 257 or more steps.
The device has been encountered which cannot be used in a ladder
pattern.
Index modification has been conducted on the ladder pattern device.
446
can use up to 9 coils.
SM400
SM400
Error details
CHKCIR
F
Coil No. 1
F
Coil No. 2
to
F
Coil No. 8
F
Coil No. 9
CHKEND
Q00J/
Q00/ QnH QnPH QnPRH
Q01
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QnU LCPU
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