Mitsubishi QCPU (Q Mode), Руководство пользователя

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MELSEC-Q
7 FUNCTION
7.15 Self-Diagnosis Function
(1) What is Self-Diagnosis Function
(a) The self-diagnosis is a function performed by the High Performance model
QCPU itself to diagnose whether there is an error in the High Performance
model QCPU.
(b) The self-diagnosis function is used to prevent the High Performance model
QCPU erroneous operation as well as preventive maintenance.
The self-diagnosis processing detects and displays the error when an error
occurs at the High Performance model QCPU power on or during High
Performance model QCPU RUN mode. It also stops High Performance
model QCPU calculations.
(2) Processing for Error Detection
(a) When the High Performance model QCPU detects an error, it turns on
ERR. LEDs. When an error is detected, special relays (SM0, SM1) are
turned ON and an error code of the error is stored in the special register
SD0. When multiple errors are detected, error codes of the latest errors are
stored in the special register SD0. For error detection, use special relays
and special registers in programs so that these devices can interlock with
sequencers and mechanical systems.
(b) The High Performance model QCPU stores 16 latest error codes. (See
Section 7.16.)
The failure history can be checked in the GX Developer function PLC
diagnostics mode.
The failure history can be stored even when the power is shut off using the
battery backup.
(3) High Performance model QCPU operation at the time of error
detection
(a) When an error is detected from the self-diagnosis, there are two types of
modes that the High Performance model QCPU operation can change to.
1) High Performance model QCPU calculation stop mode
The calculation is stopped on detecting an error, and all outputs of
modules are set to OFF if the outputs for the modules have been set to
"Clear (Default)" at the "Error time output mode" section in the "I/O
assignment" tab screen within the “(PLC) Parameter" dialog box. And
output (Y) is held.
However, the outputs of the modules are held if they have been set to
"Hold" there. The output (Y) is also held.
2) High Performance model QCPU calculation continue mode
When an error is detected, the program (Instruction) area where the
error occurred is skipped and the rest of the program is executed.
(b) The calculation "continue/stop" can be set at the "PLC RAS" tab screen in
the (PLC) "Parameter" dialog box if the following error occur.
(All parameter defaults are set at "Stop".)
1) Computation error
2) Expanded Command error
3) Fuse blown
4) I/O module comparison error
5) Intelligent module program execution error
6) Memory card access error
7) Memory card operation error
For example, when the I/O module verification error is set to "continues",
the calculations are continued in the I/O address before the error occurred.