Mitsubishi MELSEC-Q/L User Manual

440
CHKST, CHK
7.10 Debugging and failure diagnosis instructions
Function
CHKST
(1) The CHKST instruction is the instruction that starts the CHK instruction.
If the command for the CHKST instruction is OFF, execution jumps from the CHK instruction to the next instruction.
If the command for the CHKST instruction is ON, the CHK instruction is executed.
CHK
(1) The CHK instruction is the instruction used for the bidirectional operation as shown on the following page to confirm the
nature of the system failure.
(a) When the CHK instruction is executed, a failure diagnosis check is conducted with the designated check conditions,
and if a failure is detected, SM80 is turned ON, and the failure number is stored at SD80 as a BCD value.
The error code "9010" will be returned if a failure is detected.
The contact number where the failure was discovered is stored at the upper 3 digits of SD80 (see Page 442,
Section 7.10.1 (3)), and the coil number where the failure was detected (see Page 442, Section 7.10.1 (2)) is stored
at the lower 1 digit of SD80.
7.10.1 CHKST, CHK Special format failure check
7.10.1 CHKST, CHK
Setting
Data
Internal Devices
R, ZR
J\
U\G
Zn Constants Other
Bit Word Bit Word
–– ––
Basic
Universal LCPU Process
High
performance
Redundant
Command
X X X X
CHKST
CHK
Check condition (Only a contact is valid; b contact is ignored)
Up to 150 contacts can be connected
CHKST
CHK
Only input (X) can be used
X0
CHKST
X2
CHK
Y10
TO
When T0 is OFF,
program jumps to the
instruction next to the
CHK instruction.
At the detection of failure of
Contact No.: 62, Coil No.: 3
Before the detection of failure After the detection of failure
SM80
SD80
OFF
0
000
SM80
SD80
ON
0
623

Mitsubishi MELSEC-Q/L Specifications

General

Brand	Mitsubishi
Model	MELSEC-Q/L
Category	Controller
Language	English